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Call it what you may but I suppose even BIY (Built It Yourself) still describes it but is it true that one can actually design a robot lawn mower? How will one be able to choose what to use for the sensors, wheels and so forth?

You could use any wheels that worked within your design...
as to sensors... electronics is all about accuracy and sensors of all types are off the shelf ready ... as they say no need to re-invent the wheel, there is a lot of robotic kits already on the market... adapt them to your needs.

If you are thinking of doing this from a fun to do electronics hobby ... that is ok...
But if you are thinking you will save money over the existing robotic mowers, you will have to get very lucky to not waste a lot of development dollar$ starting from scratch.

It would be easier to make a mower remote controlled... fully robotic, rather costly to finally get it right... for that I would stick with what is already developed... :smile:KennyV

KennyV said:

if you are thinking you will save money over the existing robotic mowers

Click to expand...

Are there really "existing robotic mowers"? How do they work? Are they safe? Who makes them? Do they sell them to regular people? What would you use one for?

That is the same thought I did have AndyMan but from what I have gathered, they are mostly designed as a research subject. I am not sure if they have already made an impact economically.

AndyMan said:

Are there really "existing robotic mowers"? How do they work? Are they safe? Who makes them? Do they sell them to regular people? What would you use one for?

Click to expand...

Don't know if I am regular or even normal at times... but they sold me one... so I guess they might...:wink:
Totally safe, as a matter of fact you could not have an accident with them...
Only short coming is the size of your lawn... as you get over 10 to 15 thousand square feet it would be hard pressed to keep up in the fast spring growth...
They are completely quiet, will mow anytime day or night (do not need light) and will keep your lawn clipped continually... There are others but this is the one I got for my brother in Topeka, and is now mowing my sister's lawn in Phoenix ... Watch this video.
Lawn Mower That Mows the Lawn for you ? Compare Lawnmower Models Provided by Robomow
Simple to set up... :smile:KennyV

Some low life would steal it..........we use to have tractor sprinklers.......but they went out because people would steal them.
So if you are considerating buying one.........make sure you have it fully insured!

We have thieves here also ... but insurance is not the answer... If you are in a uncontrolled 'high crime' area your insurance premium will be higher than the loss risk. (technology today will help you eliminate the less educated criminal)

How you deal with thieves and how you track and trace your property will have more effect on the devious part of your community... :smile:KennyV

KennyV said:

We have thieves here also ... but insurance is not the answer... If you are in a uncontrolled 'high crime' area your insurance premium will be higher than the loss risk. (technology today will help you eliminate the less educated criminal)

How you deal with thieves and how you track and trace your property will have more effect on the devious part of your community... :smile:KennyV

Click to expand...

When I am mowing....90% of people are not home.......people are working to pay off their 500,00.00 Mortgages........so in the outer suburbs........plenty of theft.

There are ways to reduce your exposure ... and ways to increase the criminals exposure... :smile:KennyV

I appreciate the link, KennyV -- that's a cool gadget.

The key to securing a RoboMo would be to toughen it up a bit. Add a chainsaw feature -- plus a machete or two.:thumbsup: Make it really scary so the thieves will not only leave it alone but will steer clear of your yard. But do keep an attorney on retainer.

Two-Stroke said:

The key to securing a RoboMo would be to toughen it up a bit. Add a chainsaw feature -- plus a machete or two.:thumbsup:

Click to expand...

I like your thinking.:wink:.. :smile:KennyV

While my DIY lawn mower is not working yet, I find it's easier to sleep at night
if I just remove the electronic controller from the mower when not used, I'v
seen the same thing used in car sound systems. if someone is strong enough
to carry off the unit, they would never be able to use it. the unit itself
is just a collection of parts that can be replaced. sometimes when I look at the
unit I kinda wish it would walk away some night, because I know I could do better
next time(first try a making DIY lawn mower).

Now if the electronic controller and software was lost, I'd cry buckets of tears.

Sorry only pictures of unit I have are doing other tasks, up here mowing is done
for the year.

PS: My test mowing deck is an Earthwise 24Vdc

I would like to use rotary cutters, not the spinning type like the Earthwise I using.


Tommy

Tommy said:

While my DIY lawn mower is not working yet, I find it's easier to sleep at night
if I just remove the electronic controller from the mower when not used, I'v
seen the same thing used in car sound systems. if someone is strong enough
to carry off the unit, they would never be able to use it. the unit itself
is just a collection of parts that can be replaced. sometimes when I look at the
unit I kinda wish it would walk away some night, because I know I could do better
next time(first try a making DIY lawn mower).

Now if the electronic controller and software was lost, I'd cry buckets of tears.

Sorry only pictures of unit I have are doing other tasks, up here mowing is done
for the year.

PS: My test mowing deck is an Earthwise 24Vdc

I would like to use rotary cutters, not the spinning type like the Earthwise I using.


Tommy

Click to expand...

Tommy-

I am impressed. That's a really cool project. About the software, do you write it on a PC? Does the bot have a PC controlling it? Please post more about this. Please!

Another thought: can't you just back up the software so if it's lost you have a duplicate?

About the software, do you write it on a PC? Does the bot have a PC controlling it?

Click to expand...

Two-Stroke
Yes it has a on-board PC (Net book) the software is written in C#, it's Wifi connected to PC in the house, for manual
control a Bluetooth palm sized keyboard is used.

can't you just back up the software so if it's lost you have a duplicate?

Click to expand...

That would be the smart thing to do...but with it still changing daily, I do slack off on the backups.

Picture below was what it looked like 2 months ago while mowing

Tommy

Tommy said:

Two-Stroke
Yes it has a on-board PC (Net book) the software is written in C#, it's Wifi connected to PC in the house, for manual
control a Bluetooth palm sized keyboard is used.
...
Tommy

Click to expand...

Tommy-

I could go on and on with questions but I'll ask my top three:

Does the netbook on the bot run Windows? I'm guessing that it does since C# is developed by Microsoft.

Is the controller(s) that connects (via USB, I guess) the netbook to the hardware (motors, etc) an off-the-shelf item? If so, please post a link.

Did you write all the code yourself or did you find some modules (classes, I guess they'd be since it's Microsoft) online (shareware, freeware, etc.)?

This gets my vote for the best thread to date on LawnMowerForum.:thumbsup:

Does the netbook on the bot run Windows?

Click to expand...

Yes, the Mule's PC is running XP Home, the base PC in the house is running Vista.

is the controller(s) that connects (via USB, I guess) the netbook to the hardware (motors, etc) an off-the-shelf item?

Click to expand...

All the input devices are currently off the shelf USB items(Cameras,Compass 3-Axis, Gyroscope 3-Axis, Accelerometer 3-Axis, Encoders), All the output controls (lights,Motors..ect) are not plug&play but could be.
Phidgets Inc. - Unique and Easy to Use USB Interfaces
Phidgets Inc. - Unique and Easy to Use USB Interfaces
http://usdigital.com/products/encoders/incremental/rotary/kit/e6/
http://www.heidenhain.com/en_US/pro...26&tx_assistmepdb_pi1[show_article]=988175121
http://www.microsoft.com/hardware/digitalcommunication/ProductDetails.aspx?pid=021
I'm not using the below link, but sometimes wish I was.
RoboteQ AX2550 - 2 x 120 SmartAmps 12V-40V Robot Controller - RobotShop

Did you write all the code yourself or did you find some modules

Click to expand...

While the main program running on the Mule and in the house are from scratch, each
manufacture supplies drivers for a number of different programing platforms for the products
they make.

Tommy

Tommy said:

Yes, the Mule's PC is running XP Home, the base PC in the house is running Vista.


All the input devices are currently off the shelf USB items(Cameras,Compass 3-Axis, Gyroscope 3-Axis, Accelerometer 3-Axis, Encoders), All the output controls (lights,Motors..ect) are not plug&play but could be.
Phidgets Inc. - Unique and Easy to Use USB Interfaces
Phidgets Inc. - Unique and Easy to Use USB Interfaces
US Digital | Products ｻ E6 Optical Kit Encoder
[8103]=ROD%20426&tx_assistmepdb_pi1[show_article]=988175121]Products and Applications: Search by Name - HEIDENHAIN
I'm not using the below link, but sometimes wish I was.
RoboteQ AX2550 - 2 x 120 SmartAmps 12V-40V Robot Controller - RobotShop


While the main program running on the Mule and in the house are from scratch, each
manufacture supplies drives for a number of different programing platforms for the products
they make.

Tommy

Click to expand...

Thanks for taking the time to post that. It's nice to know that stuff like that is out there for sale.

Is the Mule a hobby or a potential commercial project?

Is the Mule a hobby or a potential commercial project?

Click to expand...

Two-Stroke
I'm making it to hopefully help my mom(75yr old) maintain her independent living.
she is struggling between staying in her own home, or going to an assessed living
facility, the main problem she is looking at is the cost of maintaining an independent
life is lawn care and snow removal with her husband gone(past away four years ago).

She named the Mule George, my lover calls it Georgeta because of all
the time and money I spend on it.

but after working on this project for the last 3 months, now I want one for myself.
so I will be making at least one more (once my brother seen it with the 50" plow installed he also wants one).

Tommy

Tommy said:

Two-Stroke
I'm making it to hopefully help my mom(75yr old) maintain her independent living.
she is struggling between staying in her own home, or going to an assessed living
facility, the main problem she is looking at is the cost of maintaining an independent
life is lawn care and snow removal with her husband gone(past away four years ago).

She named the Mule George, my lover calls it Georgeta because of all
the time and money I spend on it.

but after working on this project for the last 3 months, now I want one for myself.
so I will be making at least one more (once my brother seen it with the 50" plow installed he also wants one).

Tommy

Click to expand...

That's a noble cause. I wish you well. My late mother had to go to assisted living for her last seven years but the challenge was getting her to go. She suffered from dementia and had little if any awareness that she wasn't fully functional.

That's quite an impressive project. Even if you can't sell it, you're learning lots of valuable skills that can be applied to other things.

you're learning lots of valuable skills

Click to expand...

Two-Stroke
So far what I'v learned the limitations of the different consumer robotic feedback products available.

Electronic Compasses are affected by Motors, Cars, even the iron railing on my mom's porch.
Gyros drift at about 4deg per minute and can't be reset while moving(it will runaway).
Accelerometers only give feedback while Accelerating and decelerating.
Ultrasonic range sensors are affected by changing wind speeds and barometric pressures.
Laser range sensors are just too costly (5k US) and are affected by humidity.
Two wheeled differential drive system are like balancing on top of a beach ball.


Tommy

PS: because the Mule has four different attachments and is going to mow autonomously there
is lots to do, if you was also working on this type of project, you'd think it could be competed
faster I could learn from your mistakes, and you mine.

Tommy said:

Two-Stroke
So far what I'v learned the limitations of the different consumer robotic feedback products available.

Electronic Compasses are affected by Motors, Cars, even the iron railing on my mom's porch.
...

Click to expand...

All the other stuff you mentioned, I know nothing about. But I'm surprised that electronic compasses are considered a viable product -- I have one on my cell phone and it's basically worthless.

Does "George" work well if you bypass all the automatic features and just run him as you would a model airplane? You mentioned that you had a keypad (with blue-tooth) for remote control.

Two-Stroke said:

... I'm surprised that electronic compasses are considered a viable product -- I have one on my cell phone and it's basically worthless.

Click to expand...

Two-Stroke,
Electronic compasses are very precise,
phone apps are a compromise with resources and the developers programming.... some are ok... some need to be swapped for better...

Tommy, Looks like you are well into a fun & useful project :thumbsup:...
:smile:KennyV

Does "George" work well if you bypass all the automatic features and just run him as you would a model airplane? You mentioned that you had a keypad (with blue-tooth) for remote control.

Click to expand...

Two-Stroke
Yes, but it does need the Encoders(2) even when mowing with the Keyboard. one encoder keeps the
speed constant no matter what the lawn slop, the other one keeps it going in straight lines even on
uneven ground(this one can be seen in the last picture I posted, it's connected to the bar coming off
the center of george. while plowing it needs the gyro to keep going straight as possible, unless I can
find a way to use the encoders.

Electronic compasses are very precise,

Click to expand...

KennyV
From what I'v seen consumer Electronic compasses have a .1 deg resolution, I can get .006 deg
resolution with encoders, but encoders are incremental and require much processing power to
use in that function, but they are also not affected by large metal objects or electric motors. but
with encoders you must have very good contact with the ground, very hard to do in the winters
up here.

Tommy

The original design I had in my head for the mowing deck was 3 scott classic reel type for
a 50" cut path. but the earthwise has a mulching blade, don't think a reel type could do
that, and may require removing the cuttings, is that the case?

Tommy

Electronic compasses are very precise, But not something that comes to mind for small scale (within your yard) navigation, actually it would be the last... too many variables.
Navigation (electronic) airborne navigation was my field in the military...
much more accurate and easier to work with is 3-D navigation using global positioning... It is used on larger scale farming and is accurate enough to be within inches covering hundreds of acres ...
I use reel type mowers now and then in my larger areas, depending on the season. If I'm cutting short 2inch or less the reels work good taller than that it dose not work well... :smile:KennyV

Robot lawn mower. This is really a great gardening tool especially for busy people who do not have assistants at home. I would love considering owning one, but aren't these types so expensive?

It is interesting. It is fun also. Very possible. But I am sure it is expensive to build. Also expensive to maintain. Japan is doing many robotics work for the house. Very good for old people without children at home. Lawn mowing is easy compared to housework.

minkyung said:

It is interesting. It is fun also. Very possible. But I am sure it is expensive to build. Also expensive to maintain. Japan is doing many robotics work for the house. Very good for old people without children at home. Lawn mowing is easy compared to housework.

Click to expand...

That's a good point -- but isn't lawn mowing similar to vacuuming?

It is interesting. It is fun also. Very possible. But I am sure it is expensive to build. Also expensive to maintain.

Click to expand...

minkyung
If you tried to build one fifteen years ago(before ebay/creaglist) the costs to build could be grounds
for a divorce, but not today(I hope). using electric motors which have far less moving parts then a gas
motor should be easier and less costly to maintain(just a guess).

One trick I use to keep build costs down is to use wood to test an idea then replace with metal once
it is perfected(example below, testing casters). PS: not sure yet if casters are the best idea, but I
now know that two casters are better then one on uneven surfaces(like a lawn).

Tommy

Tommy-

Thanks for posting the photos. Please keep us informed as "George" evolves.

Please keep us informed as "George" evolves.

Click to expand...

Two-Stroke
I feel kinda bad posting current pictures and updates because George is now learning
to clear snow, which makes him off-topic.

Tommy

Tommy said:

Two-Stroke
I feel kinda bad posting current pictures and updates because George is now learning
to clear snow, which makes him off-topic.

Tommy

Click to expand...

There is a snow blowing forum a few lines down the main page from this one but I hope you keep posting updates here.

All kinds of off-topic stuff gets posted -- I wouldn't give that a thought.

I wouldn't give that a thought.

Click to expand...

If I step outside the forum rules, please let me know.

It seems until someone makes a Mule forum, George is going to be off topic anywhere(depending on season)

Multipurpose
Utilitarian
Lawn/Garden
Equipment

but isn't lawn mowing similar to vacuuming?

Click to expand...

In my mother's case, it's her knees that give her the most trouble while she is out side working in her
garden or the lawn, she also hates waiting for someone to do the things that causes her problems so
she'l still do them(which causes me problems). vacuuming requires much less walking and carrying.

when done, I see my mom using a fanny pack/Joystick setup to use George to carry potting soil, potted
plants and other things around.

Tommy

When you say robot lawn mower, now I am not sure what you are referring to. There are gadgets to make the lawn mower move. Remote control today is easy.

But to be called "robot" I think is more that. Robot thinks on its own. If not, then maybe almost. It's why I said it can be expensive.

When you say robot lawn mower, now I am not sure what you are referring to.

Click to expand...

minkyung
What the OP had in mind I'm not real sure either, George has three modes of operation.
1) Wifi for snow removal, my mom can control George to plow snow from a PC in her house.
2) Remotely controlled by Joystick/Keyboard to move things around her garden
3) Programed to mow the lawn autonomously

IMO George has more in common with an industrial robot then any cute toy they call a robot.
http://www.youtube.com/watch?v=-2iorMHJqwc&feature=channel
http://www.youtube.com/watch?v=2STTNYNF4lk
http://www.youtube.com/watch?v=nQtwV0Atzdc&feature=player_embedded

But with that said, i'd call George a Mule before I'd poke fun at it by calling it a robot.

I was hoping for a used one to show up on E-bay, I stopped by a local dealer looking
for the below unit, they listed a cost of $100US more then the E-bay price
http://cgi.ebay.com/ebaymotors/WARN...orsQ5fATVQ5fPartsQ5fAccessories#ht_609wt_1166

Tommy

It's why I said it can be expensive.

Click to expand...

minkyung
I'd have to agree with the above statement. I'm looking outside the Box for the answer.

I think for @$1500US you can buy a battery powered lawn mower that uses bumpers
and boundary wires to randomly path cut a very small lot.
Lawn mowers ? Eco-Friendly & Easy to use Lawn Mowers for the Perfect Lawn Maintenance Provided by Robomow

Or you could spend big bucks on something like below
YouTube - PrecisePath's Channel

But neither of these options fit my application.

IMO to crack the autonomous precise path mowing with a 50" mowing deck, 10 acre range,
and 30deg slops will take thinking "Outside the box", or like you said, a very large pocketbook.

Stepping off topic...
The below link is sweet.
YouTube - ROBOPLOW


Tommy

Tommy said:

...Stepping off topic...
The below link is sweet.
YouTube - ROBOPLOW


Tommy

Click to expand...

That's an impressive video. I tried to figure out if it's for sale or just a prototype -- I found this website. Do you know any more?

That's an impressive video. I tried to figure out if it's for sale or just a prototype

Click to expand...

Two-Stroke
Schools today are a driving force in the development of projects like in the video, the
elementary and high schools are using the Lego and Battle Bots as the draw for the kid's
attention, in colleges they do projects more like the RoboPlow video(Purdue), most if not
all serious attempts at automating things like mowing and plowing seem to come from
schools.

If you or I tackler these projects it seems we end up using lots of duct tape and doing
projects like in this video YouTube - FLYING LAWN MOWER??? MUST SEE _ NEVER BEFORE SEEN ON YOUTUBE??? ITS FLYING???? or http://www.youtube.com/watch?v=5JKb3ifRUsg&feature=related

Some of that has to due with funding, the project in the sweet snow plow video would cost you or me @15K
to put together, yet for liability reason going commercial may not be practical.

On a side note: the precise path automatic greens mower was a exception, that was a
college project that did go commercial.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

I watched the YouTube ROBOPLOW. Impressive indeed. It's controlled remotely by computer. If I was that kid outside the house, I will tell everyone it's robot. They won't know my Dad is controlling it from the garage anyway :thumbsup:

Tommy said:

Two-Stroke
Schools today are a driving force in the development of projects like in the video, the
elementary and high schools are using the Lego and Battle Bots as the draw for the kid's
attention, in colleges they do projects more like the RoboPlow video(Purdue), most if not
all serious attempts at automating things like mowing and plowing seem to come from
schools.

If you or I tackler these projects it seems we end up using lots of duct tape and doing
projects like in this video YouTube - FLYING LAWN MOWER??? MUST SEE _ NEVER BEFORE SEEN ON YOUTUBE??? ITS FLYING???? or YouTube - Remote controlled snow shovel

Some of that has to due with funding, the project in the sweet snow plow video would cost you or me @15K
to put together, yet for liability reason going commercial may not be practical.

On a side note: the precise path automatic greens mower was a exception, that was a
college project that did go commercial.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Click to expand...

You are doing very well for a DIY mower bot builder.

I enjoyed the videos -- I thought the flying mower might be a fake but decided it's probably real. The song in the background by "Frankie Goes to Hollywood" was a blast from the past.

I had the same thought about RoboPlow -- that liability might be the reason if it's not commercially viable.

I had the same thought about RoboPlow -- that liability might be the reason if it's not commercially viable.

Click to expand...

Two-Stroke
I don't know if it's, no one has cracked the autonomous mowing of the average lawn,
or because it's not commercially viable we just don't hear about them.
I seen a few web sites on college competitions in the autonomous mowing category, the
winner are the ones that can complete at least half a flat area @100ft x 100ft.

It should be a good week for George, I also have a big grin on my face looking at the parts
that came in today. one was for lack of a better term a new central nervous system, his
old one was made up of four different devices, now it'l just be one(sweet!). the other parts
are for slowing george down, right now it's top speed is 20Mph, I can't see any reason it
needs to go that fast, I'm thinking 7Mph should be about right.

Tommy

Tommy said:

Two-Stroke
I don't know if it's, no one has cracked the autonomous mowing of the average lawn,
or because it's not commercially viable we just don't hear about them.
I seen a few web sites on college competitions in the autonomous mowing category, the
winner are the ones that can complete at least half a flat area @100ft x 100ft.

It should be a good week for George, I also have a big grin on my face looking at the parts
that came in today. one was for lack of a better term a new central nervous system, his
old one was made up of four different devices, now it'l just be one(sweet!). the other parts
are for slowing george down, right now it's top speed is 20Mph, I can't see any reason it
needs to go that fast, I'm thinking 7Mph should be about right.

Tommy

Click to expand...

That is a fair maximum speed, I think. No need to let it move very fast, right? Maybe you can even bring it down to 5mph. Then you can transfer the energy to increase torque.

Tommy said:

It should be a good week for George, I also have a big grin on my face looking at the parts
that came in today. one was for lack of a better term a new central nervous system, his
old one was made up of four different devices, now it'l just be one(sweet!).

Click to expand...

As I understand it, George's "brain" is the netbook running XP Home and the "nervous system" is your new device that can (a) receive data from various sensors; (b) send instructions to various motors/switches; and (c) communicate in a form that these devices can interpret and the netbook's program(s) can understand. Am I close?

Does the new device talk to the netbook via USB (with device drivers) and the motors/sensors via regular wires?

Tommy said:

... the other parts
are for slowing george down, right now it's top speed is 20Mph, I can't see any reason it
needs to go that fast, I'm thinking 7Mph should be about right.

Click to expand...

It's funny that you brought that up. I've been thinking of a much more modest (read: less expensive) DIY project: modifying a self-propelled Lawn Boy mower (yet to be found) so it will operate via remote control -- like a model airplane. My idea -- this is the fun part - is to modify the two-stroke engine (and possibly alter the gear ratio) so the mower will go MUCH FASTER.:thumbsup:

It would be fun to have a terrifically fast, remote-control mower that would also sound cool because of the hopped-up two-stroke.

No need to let it move very fast, right?

Click to expand...

Truth be told, I'm not sure, for mowing and moving stuff higher speeds are not needed,
but for plowing snow, I don't know yet. but I'm going to keep George's speed slower then
I'm willing to run after it, in case I put bug in the software .

As I understand it, George's "brain" is the netbook running XP Home and the "nervous system" is your new device that can (a) receive data from various sensors; (b) send instructions to various motors/switches; and (c) communicate in a form that these devices can interpret and the netbook's program(s) can understand. Am I close?

Click to expand...

Two-Stroke, that is exactly right.

Does the new device talk to the netbook via USB (with device drivers) and the motors/sensors via regular wires?

Click to expand...

Yes, with the old "nervous system" I needed a four port USB hub to connect all the devices, which I believe could cause a log jam of information at times,
and because the old devices didn't have any internal memory some information could be missed, the new device has internal memory(Sweet!), not
only that, the old system could get data at a rate of 500Khz, the new one is at 5Mhz.

so the mower will go MUCH FASTER.

Click to expand...

While I'l admit these things look cute screaming around. but at my mom's age, she like a warm and fussy feeling better(I do also).

http://www.youtube.com/watch?v=9NFggE_4kOQ

Tommy

Yes, with the old "nervous system" I needed a four port USB hub to connect all the devices, which I believe could cause a log jam of information at times,
and because the old devices didn't have any internal memory some information could be missed, the new device has internal memory(Sweet!), not
only that, the old system could get data at a rate of 500Khz, the new one is at 5Mhz.

Click to expand...

That sounds much better. I can see how the old system could have trouble handling peak loads in terms of data throughput. It might work fine 99% of the time but have a meltdown in a rare case when it had to do many things at once.:confused2:

Do you have a favorite site where they discuss software for applications like George? I noticed some forums on phidgets.com but they didn't seem very active.

Do you have a favorite site where they discuss software for applications like George?

Click to expand...

Two-Stroke
There are some active forums, but sadly I have not found one where George fits in yet.

take a look at a few of the videos in the below link, it may give you an idea why.
Robot Videos

Tommy

Tommy said:

take a look at a few of the videos in the below link, it may give you an idea why.
Robot Videos

Click to expand...

Thanks for that link. It's not exactly what I'm looking for but, if I get your drift, the people on the forum are into party tricks -- not serious discussion of software problems.

I did enjoy this video of a Halloween project.

not serious discussion of software problems.

Click to expand...

Two-Stroke
There are some very sharp people societyofrobots.com, but 99% of the projects there
are toys. there is a very good industrial forum Robotforum | Support for Robotprogrammer and Users - Index
but George does not fit there either.

The problem faced by large bots run by a PC are much different then small bots that run
on microprocessors(PIC).

The problem is mine, this is my first project of this type so I don't have a network of forums
or groups of like minded people located yet.

Tommy

Tommy said:

Two-Stroke
There are some very sharp people societyofrobots.com, but 99% of the projects there
are toys. there is a very good industrial forum Robotforum | Support for Robotprogrammer and Users - Index
but George does not fit there either.

The problem faced by large bots run by a PC are much different then small bots that run
on microprocessors(PIC).

The problem is mine, this is my first project of this type so I don't have a network of forums
or groups of like minded people located yet.

Tommy

Click to expand...

Thanks for the link to Robot-Forum -- I enjoy reading stuff like that.

I had a thought that might help you. You probably know this if you are sophisticated enough to use C# but I'll post it anyway. In the same way that you might have a "bottle neck" in the device between the netbook and the motors/sensors, the netbook itself may be vulnerable to peak load problems. One way to help minimize the issue (besides spending more on a faster machine) is to use msconfig to eliminate any unneeded background programs that are running on the netbook's OS (XP Home). Here are some links:

Microsoft Support article on using msconfig

A pretty good how-to article

A list that identifies many known startup programs -- to help identify these obscure things

I thought of this because I have an Acer netbook (which I don't use very often -- just when I'm away from home and really need a computer) and I found that cleaning up with msconfig helped quite a bit -- because the netbook is so underpowered.

because the netbook is so underpowered.

Click to expand...

So far the only time George's cute little netbook(it's even pink..got it real cheap) has seemed
a bit too slow(single core processor) was when using cameras, WiFi(local network..Radmin) plus
deal with the nervous system, George was 2sec behind remote PC(dual core in the house) .
While I only debugged when George was running 5 different devices all through a single USB2 port,
and each of these devices have their own software driver and syntax. I'm eager to try the same tests
using only 3 different devices.

In your idea for a fast RC mower I would think something like the below platform could be made
to go real fast.
YouTube - robotic RC lawn mower

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

In your idea for a fast RC mower I would think something like the below platform could be made
to go real fast.
YouTube - robotic RC lawn mower

Click to expand...

That looks like it could be pretty fast. I have three old reel push mowers in my basement -- but the idea isn't appealing.

but the idea isn't appealing.

Click to expand...

I see no reason why a standard gas mowing deck couldn't be used in place of the Reel type.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

I see no reason why a standard gas mowing deck couldn't be used in place of the Reel type.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Click to expand...

I meant that using a reel mower was unappealing.

I like that little bot with two wide rubber tires but it looks expensive and if I do a remote-control mower it will be on the cheap.

looks expensive

Click to expand...

My best guess, if you had no RC gear, $1000Us. but with that said, I had set a budget of $2500Us
for the first stage of George, I can now see it more like $4000Us.

PS: I did waste @$600Us on unusable tech.

below is one sweet video from SOR
http://www.societyofrobots.com/robotforum/index.php?topic=4428.0

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

below is one sweet video from SOR
robot spider CNC

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Click to expand...

That is impressive. I have heard of manufacturing applications like that including the prediction that a lot of consumer products that have been mass produced will be custom made with tech like that in the not so distant future.

will be custom made with tech like that in the not so distant future.

Click to expand...

After spending all day standing in front of a Milling machine and Lathe just to make two of the items
below for George, I kinda wish the future would get here.


Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

After spending all day standing in front of a Milling machine and Lathe just to make two of the items
below for George, I kinda wish the future would get here.

Click to expand...

Thanks for the update. Do you have access to a machine shop at work?

Do you have access to a machine shop at work?

Click to expand...

Yes, at the main office which is only 100miles from my place.

I got George home last night so I didn't get a chance to test the changes made.

It toke me two days to make and install, I sure it would help if I was a machinist.

In the "It looked good on paper" category. I had planed to have the chain/gears tucked up
inside the tire rim to help keep crap out of it, but with the gear sizes used, when the chain
is tight there was only 1/8 of an inch clearance between the chain and rim, and with the run-out
in the rim(cheap rim) I could see it hitting at some point.




Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

Yes, at the main office which is only 100miles from my place.

I got George home last night so I didn't get a chance to test the changes made.

It toke me two days to make and install, I sure it would help if I was a machinist.

In the "It looked good on paper" category. I had planed to have the chain/gears tucked up
inside the tire rim to help keep crap out of it, but with the gear sizes used, when the chain
is tight there was only 1/8 of an inch clearance between the chain and rim, and with the run-out
in the rim(cheap rim) I could see it hitting at some point.




Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Click to expand...

George has a very heavy duty look to him, as I guess he must if he's required to push snow around.

Does George have suspension? I was a bit surprised to see the spring in the latest photo.

Does George have suspension?

Click to expand...

The springs are needed because of the DC motors which can generate full torque in
a faction of a second. when I first started programing the drive software and I got it
wrong it could go from full speed forward to full speed reverse in one second, without
the springs all my motor mount brackets would need to be much stronger.


Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

The springs are needed because of the DC motors which can generate full torque in
a faction of a second. when I first started programing the drive software and I got it
wrong it could go from full speed forward to full speed reverse in one second, without
the springs all my motor mount brackets would need to be much stronger.


Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Click to expand...

Ahh... it's for the motor.

One of the selling points of the Tesla car is the instant response. You get used to it but all gasoline engines have a lag between the time you press the throttle and the time the power is applied. Electric engines have no such lag.

Last night I got a chance to check out the new gear boxes on George, seems perfect..

But, because I had to let the air out of George's tires to get it to clear the pickup's bed cap(1" too tall)
I had to remove the tires to get them aired up, thats when I spotted a problem.

A missing snap ring that keeps the chain link together, So glade I spotted it now.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy-

What does your mom think of George? I'm sure that she appreciates all that you do for her but how does she feel about the controls, etc? Are you having to adapt the "user interface" as you go? It would be fun to hear from her in this thread.

What does your mom think of George?

Click to expand...

While I have not given my mom control of George yet, I'm sure she'l be fine once she does.
three years ago I had a web site that needed daily changes to the HTML and because I'm
always on the lookout for things to keep her busy, I showed her how to do it and then gave
the job to her, while I did have to write some software to make it easier on her, she did pick
it up and was able to do the job, I hoping the same thing happens with george. I will have to
make changes to the user interface, like.. now I'm using a small palm sized keyboard for manual
control, but for my mom I'l have to go to a joystick , she'l have problems dealing with the
small keys on a small keyboard.

Once I get all the bugs worked out of George I'l give her a try at it, but I have to be very careful
not to give george a chance to scare her.

Theirs been a few times over the last three months that george has scared me.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Tommy said:

While I have not given my mom control of George yet, I'm sure she'l be fine once she does.
three years ago I had a web site that needed daily changes to the HTML and because I'm
always on the lookout for things to keep her busy, I showed her how to do it and then gave
the job to her, while I did have to write some software to make it easier on her, she did pick
it up and was able to do the job, I hoping the same thing happens with george. I will have to
make changes to the user interface, like.. now I'm using a small palm sized keyboard for manual
control, but for my mom I'l have to go to a joystick , she'l have problems dealing with the
small keys on a small keyboard.

Once I get all the bugs worked out of George I'l give her a try at it, but I have to be very careful
not to give george a chance to scare her.

Theirs been a few times over the last three months that george has scared me.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

Click to expand...

That's a good idea. Before you changed George's gear ratio, he could do 20mph -- potentially scary given that he has spinning blades.

Please keep us posted.

There is one other big consideration, George can't frustrate my mom, and I can see
snow and ice as a big source of frustration. I put some grey cells on that problem and think
I have a plan. feel free to offer any ideas.

Tommy
All opinions expressed are mine alone, and subject to change as information is gained.

George's first snow!

YouTube - george_0001.wmv

Tommy

Tommy said:

George's first snow!

YouTube - george_0001.wmv

Tommy

Click to expand...

Wow, George is a pretty powerful machine.

Thanks for posting the video.

Has your mom used it yet?

Has your mom used it yet?

Click to expand...

Two-Stroke
While she has stopped over to watch me work on George I will not pushed her to take control
until I have that warm & fuzzy feeling about George(trust is earned, not programed). and as you
can see from the video George is still not ready for low care operations(weatherproofing). this
next weekend I hope to take George back to the shop to install plow lifting(farm&fleet had a sale
on 2000lb 12Vdc winches for $49.00).

While the first test of snow plowing did go good IMO, It did point out the need to lift the plow.
it also showed the Gyro is not going to work as intended(back to the drawing board).

Tommy

Very cool thread , very cool project. I read the whole thread last night. I have very limited knowledge of electronics and computers, but this is still very interesting to me. Please keep us posted. You are doing great.:biggrin: Dusty

I concur with you; I have not quite an advanced knowledge of computers and electronics but this has not deterred me from getting the flow of the whole discussion. Very informative! :thumbsup:

picture of my mom's first try with George. she said she like it and would use if I can figure out the depth perception issue.

Tommy

Tommy said:

picture of my mom's first try with George. she said she like it and would use if I can figure out the depth perception issue.

Tommy

Click to expand...

Was she able to clear some snow with George? Can't she just look out the window to get depth perception?

Thanks for the update.

Can't she just look out the window to get depth perception?

Click to expand...

Two-Stroke
At my place I can sit in the kitchen and watch everything George is doing, but not at my mom place,
she is going to need the cameras or something.

Tommy

Now that spring is here, Its time to get serious about the mowing issue.

First try is going to be with three reel mowers.

picture of the first one temperately mounted.

Tommy

Tommy said:

Now that spring is here, Its time to get serious about the mowing issue.

First try is going to be with three reel mowers.

picture of the first one temperately mounted.

Tommy

Click to expand...

Tommy, it's good to hear from you.:smile:

Was the snow plow useful for your mom? Please fill us in.

The newest project is looking good. Thanks for the pictures.

Was the snow plow useful for your mom?

Click to expand...

Two-Stroke, yes and no. useful only in she didn't have to do it or have it done, because
I used george to do it. truth be told I was watching the weather very closely for chances
to use the plow on george this winter, and having great fun while doing it.
Winter was not all that generous with snow this year, with only eight opportunities to test
weights and controls, George still does not give me a warm & fuzzy feeling.

but on the plus side, I do have a warm&fuzzy feeling about the PC control of the drive system,
I feel comfortable enough to removed the springs from the motor mounts.

this morning I got the other two mowers temp. mounted

Tommy

Tommy said:

Two-Stroke, yes and no. useful only in she didn't have to do it or have it done, because
I used george to do it. truth be told I was watching the weather very closely for chances
to use the plow on george this winter, and having great fun while doing it.
Winter was not all that generous with snow this year, with only eight opportunities to test
weights and controls, George still does not give me a warm & fuzzy feeling.

but on the plus side, I do have a warm&fuzzy feeling about the PC control of the drive system,
I feel comfortable enough to removed the springs from the motor mounts.

this morning I got the other two mowers temp. mounted

Tommy

Click to expand...

I imagine that it would be fun to wait for snow to have an opportunity to test George.:biggrin:

Basic (probably obvious) questions about George as a mower:

The reel mowers go in front of the main unit -- correct? (As opposed to being towed.)

Does George steer by varying the speed of the large wheels? To turn left the left wheel would slow down relative to the right, for example.

Thanks again for posting.

The reel mowers go in front of the main unit -- correct?

Click to expand...

Does George steer by varying the speed of the large wheels?

Click to expand...

You are thinking correct, with the current test mowing deck the smallest turn radius
the Mule can make with the mower down(in contact with the ground) is @200ft. in
practice George is going to be mowing straight lines. when it's stopped the mower
deck will be up for zero radius turns.

I'd give this approach an 40% chance of lasting longer then four weeks of testing before
I scrape it and move on to plan B.

but I do love how compact the mower deck is while raised.


Tommy

Tommy:

On the subject of turning with a mower attachment: did you consider a rotary mower with a couple of caster wheels? That's how many if not most "zero-turn" mowers achieve their ability to mow close to obstacles.

I might add that a lot of high-end mowers (used on golf courses, etc.) use a "gang" of reel mowers. You get a nice, clean cut - some of the posts I've read on this forum have changed my mind somewhat on the merits of a reel mower.

did you consider a rotary mower with a couple of caster wheels?

Click to expand...

Last fall I tested that approach with a single 20" rotary mower(Earthwise 24Vdc), But I
got to thinking about the power requirements and footprint of a +40" cut path in that style
and I lost interest(I also didn't like the noise of even a 20" mowing deck).

I gave George the power to push a 50" plow through 10" of snow, it should have the
power needed to push 3 20" reel mowers with friction drive. with this approach no
extra energy would be needed to power the mowing deck(it would also be very quite),
energy would be needed for lifting and lowering the mower(needed for turns) but the
amount needed would be much less then powering the mower deck.

with that said, plan B is adding two more batteries to power the reel mowers(I already have
the motors) and adding casters.

I'm very skeptical that a friction drive approach is going to give me satisfactory resolutes
but I gotta give it a chance(four weeks at most) due to the energy savings.

While I do force myself to stay on task and not think about the next phase, it does play
a part in the options I test(next phase is using solar cells to charge George's batteries) .

Tommy

Tommy said:

Last fall I tested that approach with a single 20" rotary mower(Earthwise 24Vdc), But I
got to thinking about the power requirements and footprint of a +40" cut path in that style
and I lost interest(I also didn't like the noise of even a 20" mowing deck).

I gave George the power to push a 50" plow through 10" of snow, it should have the
power needed to push 3 20" reel mowers with friction drive. with this approach no
extra energy would be needed to power the mowing deck(it would also be very quite),
energy would be needed for lifting and lowering the mower(needed for turns) but the
amount needed would be much less then powering the mower deck.

with that said, plan B is adding two more batteries to power the reel mowers(I already have
the motors) and adding casters.

I'm very skeptical that a friction drive approach is going to give me satisfactory resolutes
but I gotta give it a chance(four weeks at most) due to the energy savings.

While I do force myself to stay on task and not think about the next phase, it does play
a part in the options I test(next phase is using solar cells to charge George's batteries) .

Tommy

Click to expand...

Even with fluffy, dry snow that's a lot of power. I'm sure that George has enough power for the friction-driven reel mowers -- the issue is what to do on turns.

After not hearing from you for months, I am glad that you're back posting here.

Got a chance to test the Reel Mowers on the Mule this weekend(mowed my and my mom's lawn).

The friction drive system worked better then I expected(given the hacked together setup).

Tommy

Tommy said:

Got a chance to test the Reel Mowers on the Mule this weekend(mowed my and my mom's lawn).

The friction drive system worked better then I expected(given the hacked together setup).

Tommy

Click to expand...

Cool - what's the acreage and how long did it take? What's the next step?

Tommy said:

Got a chance to test the Reel Mowers on the Mule this weekend(mowed my and my mom's lawn).

The friction drive system worked better then I expected(given the hacked together setup).

Tommy

Click to expand...

It's good to hear from you, Tommy.

Does it work in robotic mode at all or is it pretty much remote-controlled?

Does it work in robotic mode at all or is it pretty much remote-controlled?

Click to expand...

Two-Stroke, all tests so far have been performed with a wired joystick and me walking along
side inspecting results. with that said, I'v come to believe that putting the cameras on George
last fall for ROV operations(snow removal) was a crackhead thing to do, last fall I was writing
software ,testing sensors and running programmed cut paths, once the cameras went on all
that work was stopped, and both me and George missed out on almost six months of learning.
but we did have lots of fun playing in the snow and cold from the comforts of home.

what's the acreage and how long did it take?

Click to expand...

mystreba, the areas I used for the first test of the friction driven reel mowers was less then
a 1/4 acre which the 40" deck made short work of(less then an hour of cut time). total area
George is projected to do is 5 acres in 6 hours(one charge cycle).

What's the next step?

Click to expand...

Back to the basics. the longest cut path the Mule has to do is 10212.15 inches, the next step
is making it possible for the Mule to make a programmed straight cut path over that distance.

Tommy

Tommy said:

Two-Stroke, all tests so far have been performed with a wired joystick and me walking along
side inspecting results. with that said, I'v come to believe that putting the cameras on George
last fall for ROV operations(snow removal) was a crackhead thing to do, last fall I was writing
software ,testing sensors and running programmed cut paths, once the cameras went on all
that work was stopped, and both me and George missed out on almost six months of learning.
but we did have lots of fun playing in the snow and cold from the comforts of home.


mystreba, the areas I used for the first test of the friction driven reel mowers was less then
a 1/4 acre which the 40" deck made short work of(less then an hour of cut time). total area
George is projected to do is 5 acres in 6 hours(one charge cycle).


Back to the basics. the longest cut path the Mule has to do is 10212.15 inches, the next step
is making it possible for the Mule to make a programmed straight cut path over that distance.

Tommy

Click to expand...

George sure is a robust machine. The idea of any battery-operated mower being able to operate for six hours, cutting five acres on a single charge is amazing. Have you told us about the battery pack? This thread has been going for so long that I've forgotten all that's in it.

Does George self-correct while he's trying to navigate a straight path?

I'm not surprised that he doesn't operate in fully robotic mode -- that's very, very complex project. What you've done so far is certainly impressive. Keep up the good work and let us know when you make progress.

Just a thought: doesn't George deserve his own website -- including his own domain name?

Have you told us about the battery pack?

Click to expand...

Not sure, but when I started on the Mule I figured 480Ah(8 car batteries) of battery power would be
needed,I'v been operating with 240Ah(4 car batteries) over the winter. if I can use the friction drive
for mowing I can get by on just over 300Ah(6 car batteries). As is I have to use sandbags to replace
the weight of the missing batteries.

This thread has been going for so long that I've forgotten all that's in it.

Click to expand...

When I started George I set a one year build time, but with all the down time this winter I'm
going to need more time I think.

Does George self-correct while he's trying to navigate a straight path?

Click to expand...

This is an area George should excel with it's installed sensors, I should know by sunday if true
,if not, plan B.

doesn't George deserve his own website -- including his own domain name?

Click to expand...

Because no effort or costs have be put towards looks, George is camera shy.


Tommy

Tommy said:

Because no effort or costs have be put towards looks, George is camera shy.

Click to expand...

By that definition, I reckon I should avoid cameras at all cost then.

Tommy said:

Not sure, but when I started on the Mule I figured 480Ah(8 car batteries) of battery power would be
needed,I'v been operating with 240Ah(4 car batteries) over the winter. if I can use the friction drive
for mowing I can get by on just over 300Ah(6 car batteries). As is I have to use sandbags to replace
the weight of the missing batteries.


When I started George I set a one year build time, but with all the down time this winter I'm
going to need more time I think.


This is an area George should excel with it's installed sensors, I should know by sunday if true
,if not, plan B.


Because no effort or costs have be put towards looks, George is camera shy.


Tommy

Click to expand...

Wow, that's a lot of battery power -- -- and a lot of weight. I didn't realize George was that heavy.

I'm interested in the results of your test run on Sunday. Please keep us posted -- and thanks for taking the time to update this thread.

I'm interested in the results of your test run on Sunday. Please keep us posted

Click to expand...

Two-Stroke, tests cut short by Mother's day commitments.

As is the Mule has two devices for maintaining a straight cut path. The first a Yaw sensor, second
a USB digital compass, I only tested the compass because after lots of head scratching and lots
of unneeded software changes I discovered the Yaw sensor was interfering with the compass and
had to be removed for this test.

The tests of the digital compass showed it to be a useful but limited sensor, while in a open field
it was able to keep the Mule on a set coarse to +- .3 deg over the 850ft path(Sweet!), but while
in an area with large metal objects(cars, storage sheds, etc..) the Mule could not maintain a
bearing, the objects would change the magnet fields causing the Mule to change coarse(crap!).

an interesting test would be to see if the digital compass could be used to map out the Mule's
environment using magnet fields kinda like an MIR(Magnet Imaging Radar).

Tommy

Tommy said:

an interesting test would be to see if the digital compass could be used to map out the Mule's environment using magnet fields kinda like an MIR(Magnet Imaging Radar).

Click to expand...

This may sound crazy, but would it be possible (cost notwithstanding) to use radar or lidar?

GPS?

Tommy -- thanks for the update.

but would it be possible (cost notwithstanding) to use radar or lidar?

Click to expand...

mystreba
LIDAR(or Laser ranging) is a common tool used in military/Universities grade unmanned vehicles, but that
cost notwithstanding part keeps that technology off the Mule.

In the consumer electronics market(hobby robots) Ultrasonic range sensors are in common use, some
having ranges of 200ft at a cost of about $100us, but that technology is best suited for indoors use.
because temp, humidity and wind speed can change it's recorded values.

I can't see wind speed changing the magnet fields.

Tommy

Update:

Completed tests of friction drive Reel mowers on George, and while it had it's advantages
it couldn't give repeatable results, too many things can stop the Reel from turning.

Options I can think of.
1) Motorize(electric) the Reel Mowers
2) Motorize(electric) a standard mower deck, something like a JD 38" mower deck.
3) Use multipliable over the counter electric mowers to make a 38" cut path.

The fastest(grass needs cutting) seems to be #3.

Tommy

Will there be a flat spot on top for my cat to sit so I can shoot a sweet YouTube video?

Will there be a flat spot on top for my cat to sit

Click to expand...

Jetblast, your cat better have nerves of steel, because these electric mowers make
as much noise as a gas motor.

while test mounting the 2 24vdc rotary mowers I found I could not get them closer
then 1.5" together without cutting parts(destroying the mower), going to test using
a caster at that split in hopes it diverts the grass to either mower.

Tommy

Update

First tests of the 38" electric mower deck went good, wasn't stopped by tall grass(~8") or
the last years bits and pieces of corncobs(stuff that would stop the Reel mowers).

Not happy with the size(footprint) of the test unit, I did like the small footprint of the Reel mowers.

Tommy

Thanks for the update, Tommy.

How is the guidance system? I think you said that you were going to test how accurately George can navigate.

How is the guidance system?

Click to expand...

Two-Stroke, I'm still working with the digital compass because it did keep the Mule
on a straight heading with the reel mower, yes it did waste a lot of energy trying
to turn the reel mowers with its six fixed wheels spring loaded to the ground but
it did work, the electric rotary deck I'm testing now has two casters to maintain
cut hight which can turn any direction with little effort from the Mule which should
require less energy(from the drive system).

I did test the compass as it was set up for the reel mowers, but the electric motors
on the new test deck interfered with it's reading, last night I did get a chance to move
the compass to a new location and should know today if interference is gone.

some quick calculations seems to suggest that to cut 4"(off the top) of grass in a 4 acre
field using a 38" electric deck would require close to 300Ah of batteries, while cutting 1" (off the top)
would need 120Ah.

I hope to get a chance to replace the mulching blades with standard blades to see if the
energy requirements change.



Tommy

WOW, this thread has gotten a lot of mileage!

Everytime I turn around, there's another post in it!

Tommy said:

Two-Stroke, I'm still working with the digital compass because it did keep the Mule
on a straight heading with the reel mower, yes it did waste a lot of energy trying
to turn the reel mowers with its six fixed wheels spring loaded to the ground but
it did work, the electric rotary deck I'm testing now has two casters to maintain
cut hight which can turn any direction with little effort from the Mule which should
require less energy(from the drive system).

I did test the compass as it was set up for the reel mowers, but the electric motors
on the new test deck interfered with it's reading, last night I did get a chance to move
the compass to a new location and should know today if interference is gone.

some quick calculations seems to suggest that to cut 4"(off the top) of grass in a 4 acre
field using a 38" electric deck would require close to 300Ah of batteries, while cutting 1" (off the top)
would need 120Ah.

I hope to get a chance to replace the mulching blades with standard blades to see if the
energy requirements change.



Tommy

Click to expand...

It's good news if the navigation system is working. It seems to me that getting the mowing units to work should be relatively straightforward -- no great complexity there.

Keep up the good work -- and thanks again for keeping us posted. :thumbsup:

Everytime I turn around, there's another post in it!

Click to expand...

twall, with only four months until this project needs to be completed(self set deadline) I do
feel the need to keep things moving, not a day goes by without something being done to the Mule.

It seems to me that getting the mowing units to work should be relatively straightforward -- no great complexity there.

Click to expand...

Two-Stroke, It seems the gene pool is not all that fair for some of us, because for me the nuts & bolts
of things causes me lots of trouble, I started working on a mowing deck in January yet I'm still working
on it.

It's good news if the navigation system is working.

Click to expand...

I was not able to find a good location for the compass where the electric motors of the mowing deck
would not interfere with the sensor(even tried 4' above the mule). While I'm waiting for the navigation
systems secret weapon to get here I'm working on the Yaw sensor.

Tommy

It's good news if the navigation system is working.

Click to expand...

Two-Stroke, the current envisioned navigation system is a collection of senors.

Yaw senor is just two rotary encoders, one is located at Georges center of turn
and is calibrated in degrees, the other has an 8" wheel that is used as an odometer, the
easiest way to describe it is a Scully.

Digital Compass this is an over the counter, plug&play device that can measure the
earth's magnetic field an allow you to use that information in your computer software.

Gyro this is also a over the counter, plug&play device that is used to stabilize George's
two wheel drive/turns system while pushing snow or mower deck.

Accelerometer this is also a over the counter, plug&play device that is used to stabilize
George while accelerating and decelerating.

GPS this is also a over the counter, plug&play device that allow you to use GPS information
in your computer software.

secret weapon the real secret is if it'l work! last few years we'v been able to buy electronic
pet locators, I think they could be used to correct for GPS position errors.


First tests of the Yaw Sensor on sunday products some interesting results, the first test was to
see if the Yaw sensor could keep the Mule tracking straight over the test area with the mower
deck off. and it failed, just because I was there I tested it with the mower running and it did a
sweet job, made it from one end to the other?. seems the tall grass was causing the sensor to
float?, when I tried it with the mower deck off and me pushing down on the sensor it also worked.

Test area pictured below


Tommy

Tommy said:

Two-Stroke, the current envisioned navigation system is a collection of senors.

Yaw senor is just two rotary encoders, one is located at Georges center of turn
and is calibrated in degrees, the other has an 8" wheel that is used as an odometer, the
easiest way to describe it is a Scully.

Digital Compass this is an over the counter, plug&play device that can measure the
earth's magnetic field an allow you to use that information in your computer software.

Gyro this is also a over the counter, plug&play device that is used to stabilize George's
two wheel drive/turns system while pushing snow or mower deck.

Accelerometer this is also a over the counter, plug&play device that is used to stabilize
George while accelerating and decelerating.

GPS this is also a over the counter, plug&play device that allow you to use GPS information
in your computer software.

secret weapon the real secret is if it'l work! last few years we'v been able to buy electronic
pet locators, I think they could be used to correct for GPS position errors.


First tests of the Yaw Sensor on sunday products some interesting results, the first test was to
see if the Yaw sensor could keep the Mule tracking straight over the test area with the mower
deck off. and it failed, just because I was there I tested it with the mower running and it did a
sweet job, made it from one end to the other?. seems the tall grass was causing the sensor to
float?, when I tried it with the mower deck off and me pushing down on the sensor it also worked.

Test area pictured below


Tommy

Click to expand...

Thanks for the detailed update, Tommy.

Since you have so much data to work with from all these sensors, does the decision-making software have to judge the priority given to different (potentially conflicting) pieces of data?

Example: if the GPS thinks all is peachy (on course) but the yaw sensor thinks it has been bumped in another direction, the software has to decide which to believe -- but how?

What does your mom think of this? This is still a project to help her cope with yard work and snow -- correct?

Also, some video of your testing would be fun. :thumbsup:

Since you have so much data to work with from all these sensors, does the decision-making software have to judge the priority given to different (potentially conflicting) pieces of data?

Click to expand...

Two-Stroke, its more timing issues(speed of senors) then prioritizing in the current configuration.
If the Yaw senor drops in a rabbit hole, the mule well stop and wait(up to 5 seconds) for it's position to be calculated,
the greater the amount of Yawing of George the slower it will go(over 1.5deg it stops).

Update times for senors
Yaw senor 100 times a second
Gyro, Compass, Accelerometer 20 times a second
GPS 1 time a second
Beacons(secret weapon) 5 seconds to get location

What does your mom think of this?

Click to expand...

I use the Mule(with Joystick) to cut both of our lawns, so she's alway happy to see George, and
she's always quick to question his progress.

This is still a project to help her cope with yard work and snow

Click to expand...

IMO George has already helped her, she hasn't had to deal with either so far. granted I did
have to do snow by camera(ROV mode) this last winter,and I'm doing the mowing by joystick
still, but it does get it done, so she didn't have to worry about it.

If I can get the navigation system working theres no reason plowing could not be programmed.

some video of your testing

Click to expand...

As is I used simple hand-tools found in most junk drawers to put this stuff together,
it's not a pretty picture, but can do.

Tommy

I still can't quite understand how George's controlling software deals with it when input sensors give conflicting information. :ashamed:

It's great that you are getting a lot of use out of George as a remote control mower while still working on his robotic capability.

I know George is very heavy -- probably too heavy to lift -- can you transport him in a trailer or the bed of a truck?

Thanks again for the updates, Tommy.

I still can't quite understand how George's controlling software deals with it when input sensors give conflicting information.

Click to expand...

Two-Stroke, each sensor has it's function, and limitations. The absolute position
senor is the beacons, but it limited to only four of them, and it takes up to five seconds to get a good
position fix. to over come the four beacon limit the GPS is used, because it can track George to within
20ft it is used to determined which four to use(my house's four beacons or my mom's four beacons).
The Yaw sensor is used to overcome the five second limitation of the beacons, the Yaw sensor can
track the Mule to within ~.1 inch at mowing speed and uses this information in between beacon
updates to help keep george on coarse.

I know George is very heavy

Click to expand...

The idea weight for george is 500lb for plowing snow with chains, and mowing with these 10 inch wide turf safe tires.

can you transport him in a trailer or the bed of a truck?

Click to expand...

George has been on two road trips(back of pickup truck) so far, both last winter to do modifications
that needed a machine shop.

probably too heavy to lift

Click to expand...

That is kinda funny, I was thinking the same thing.
last fall I was able to pick up one side of george to through a block under him to change a tire,
now I need a floor jack.

Tommy

Update:

Test Yaw Sensor, but I used the GPS to gage results. I wrote into the Mule's software to record the
GPS data every second and save to a file, then I put together some software to load a map(from Google Earth)
of the test area, then painted on the GPS data(from file).

The Yaw sensor needs to keep the Mule on coarse in between beacon updates(every 5 seconds), so
IMO if it can keep the Mule tracking straight the length of the test area(850ft) it should have no problem
with the ~10ft in between beacon reads.

The first picture is me walking the Mule around the Mowing area as it recorded the values, as a way
to test the GPS values(it did an ok job).

the next picture is the first tested Yaw senor ground contact wheels
then the GPS data(did a very bad job).

the next picture is the second tested Yaw senor ground contact wheels
then the GPS data.

the next picture is the third tested Yaw senor ground contact wheels
then the GPS data(did a very bad job).

last picture is the Mule in the test area.

Tommy

I thought you had to transport George between your house and your mother's -- that's why I asked about loading the device. I guess you live close together.

It looks like you've taken on a huge cutting area behind many houses -- are all those people getting some free mowing?

The erratic GPS readings remind me of mountain biking. GPS was a true game-changer in that it gave me greatly expanded navigational capability. I carry a GPS that attempts to record a point every second. Sometimes it gets something nonsensical and is smart enough to throw away the point. Sometimes it gets a point that doesn't differ much from the previous point -- and throws that away. Sometimes it records a bad point or a series of bad points but can't tell they're bad. :laughing:

I can view the points on Google Earth (or Google Maps) after converting the data with a program called GPSBabel. It's interesting to view the data after exploring a new (to me) area.

Thanks for taking the time to post the pictures. It's very interesting to follow this amazing DIY project of yours.

It looks like you've taken on a huge cutting area behind many houses -- are all those people getting some free mowing?

Click to expand...

That reminds me of last winter, I asked everyone on my block if it'd be ok for me to use George
to plow their snow, not one said no. but one time we got hit hard(5ft drifts) and I slept throw
it, while I was working on a recharge of George one of them brought over a snow blower and
got us(me and george) out of trouble. what comes around goes around.

As it turns out mowing that large field is much easier then either mine or my mom's.
because we are both covered by trees, storage sheds, bird feeders, etc.. It seems
possible to do that field by GPS alone with the 38" cut path.

one thing I find interesting, it's possible to view the speed of george on the software map,
in the first picture above I plotted the GPS data as lines, then the last three as circles(the size of cut path)
as george went faster the circles got farther apart per second, so, going slow gives a solid color,
going fast gives line of circles.

This is where limited Mechanical aptitude can slow a project down, so far I'v been working
on developing a Yaw Senors for over six months with very, very limited success.


Tommy

I can relate to the idea that George would be OK with GPS only in an open field but not OK where there's a lot of tree cover, etc.

Keep up the good work, Tommy.

Video of george mowing in a confined area.



Tommy

Tommy said:

Video of george mowing in a confined area.

Tommy

Click to expand...

I was impressed by how well George articulated around the obstacle (it looked like a phone box).

Does he go faster when the area is more open?

Thanks for posting, Tommy.

Does he go faster when the area is more open?

Click to expand...

Two-Stroke, this test was using what I call CNC Mode, which mimics a CNC machine used
in the manufacturing industries that uses what is called G Code programming, in it's simplest
terms a G Code program is a text file that contains step by step instructions to accomplish a
task.

In george's case a line in the file may look like "GC3 180.040.0"
where the first character defines the type of move(G=george moves forward, X=moves Backward).
the second character defines the sensor to use(C=compass, Q=Yaw, S=GPS, G=Gyro ect..)
the third character defines the Max speed george is to move(1 to 6, 1 is very slow, 6 is his top speed)
the actual speed is a function of how on course george is (slows down when off course).
the next 6 spaces sets the direction that george is to move, the last 8 spaces of the line tells
george how far to go.

so the line "GC3 180.040.0" tells george to go forward, using the compass, at half speed
traveling at 180.0deg.(south) for 40.0ft. once the move is completed it goes to the next line.

All moves done in the video was at speed 3(half speed), but with that said george will never
win any races.

Tommy

Tommy said:

Two-Stroke, this test was using what I call CNC Mode, which mimics a CNC machine used
in the manufacturing industries that uses what is called G Code programming, in it's simplest
terms a G Code program is a text file that contains step by step instructions to accomplish a
task.

In george's case a line in the file may look like "GC3 180.040.0"
where the first character defines the type of move(G=george moves forward, X=moves Backward).
the second character defines the sensor to use(C=compass, Q=Yaw, S=GPS, G=Gyro ect..)
the third character defines the Max speed george is to move(1 to 6, 1 is very slow, 6 is his top speed)
the actual speed is a function of how on course george is (slows down when off course).
the next 6 spaces sets the direction that george is to move, the last 8 spaces of the line tells
george how far to go.

so the line "GC3 180.040.0" tells george to go forward, using the compass, at half speed
traveling at 180.0deg.(south) for 40.0ft. once the move is completed it goes to the next line.

All moves done in the video was at speed 3(half speed), but with that said george will never
win any races.

Tommy

Click to expand...

Thanks, Tommy. Knowing how things work is a great interest of mine and different types of computer coding is a particular interest.

Last mowing season I first tried using rotary style mowers(3) in there friction drive mode,
but found them to be unreliable because small stick, corncobs just about anything could
stop them causing the mowers drive wheels to stop turning. I then used two standard type
electric mowers connected together to give me a 38" cut path, but found them to be very
under powered and very noisy. I'm now trying rotary style mowers but with electric motors
to drive the blades and casters so George can still do ZRT.

Tommy

I understand this is an old(dead horse) topic, but just want to share a short video
of snow plowing with George.


Tommy

Tommy said:

Video of george mowing in a confined area

Click to expand...

Tommy said:

I understand this is an old(dead horse) topic, but just want to share a short video
of snow plowing with George.

Click to expand...

That is really cool! :thumbsup::thumbsup:

Tommy said:

... I'm now trying rotary style mowers but with electric motors
to drive the blades and casters so George can still do ZRT.
Tommy

Click to expand...

Just stumbled across this thread and I think it is amazing. I would love to hear an update on how the electric drive reel mowers worked out.

I've been knocking around the idea of building an autonomous mowing rig myself for over a year now and it's great to see what worked for you and what didn't. Professionally I'm a computer programmer so while the software side is immensely complex, I know I can figure that part out and doesn't worry me that much. My dad is a mechanic and I've got friends that are good with circuits if I get stuck. The big problem I wrestle with is the pure engineering options and scale of the device. Here is my current thinking for anyone interested:

* Small as possible. While George can tackle a 4-acre field, I think most needs are smaller and I can always use multiple to scale up if needed.

* Small gas powered engine generating electricity. All the off the shelf generators are too large but there are really good small light 4-stroke engines available these days to build a custom small generator I think. I have a 4-stroke blower that is as light as any 2-stroke and is much quieter. Going gas saves a lot of weight since gasoline is a very dense energy source. It also means I could have very long run times. I can skip this during prototyping by using small light batteries with limited run time.

* Powered rotary reel cutters in a 3-way gang configuration. This is why I'm so interested in how this worked for you. Because I want mine to be small, I really want each reel to be 6-8" wide for a total deck size of less than 20". Nothing seems to be commercially available though. I've even considered a crossbar style cutter which can easily be scaled down but it doesn't lift and cut like a reel would.

* Mower unit would be dumb. I would use blue-tooth/wi-fi to send sensor information back to a control unit and have decisions made there. This has serious limitations but it's the fastest way to make everything work for a prototype. Once validated a plan to move more smarts down to the mower could be done.