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With the 18" wheels the mule could move 20mph in a runaway condition(like loss of feedback)
somewhere there should be a rule written that you should not let your Mule run faster then you
can. so I geared it down to 7mph max.
through test I found one rear caster to be unreliable, testing two now but see me replacing the
casters completely with a rear drive wheel
Tommy
If that is spoken from experience then I think we need to hear more.Quote:
Originally Posted by Tommy_T
jRaskellQuote:
If that is spoken from experience then I think we need to hear more.
The mule has been very well behaved so far, while there has been a few software oops in the
beginning, each time they happened I immediately checked to see if any seen it(no one did). Maybe
that should also be a rule, if no one seen it, it didn't happen.
The reason I'm more concerned now is I'm in the house while the Mule is outside plowing snow, before
I'm standing next to the Mule ready to hit the E-Stop if theres a problem.
Tommy
I love these projects! Video! We demand video!
As soon as we get some snow to plow I'l get some footage.Quote:
Video!
My lover knows how much I'm been looking forward to some snow, and yesterday as I was
driving to chicago, it did start to snow(flurries) at home, so she calls me telling me the Mule
is outside yelling my name and watching the snow come down. guess she had to rub it in
that we were getting snow but I couldn't be there. by the time I got home the snow was all
gone.
Tommy
There comes a time in every young Mule's life when it needs to man-up(wear chains)
Tommy
The Mule's first snow
[ame="http://www.youtube.com/watch?v=xAboRavU2rw"]YouTube - george_0001.wmv[/ame]
Tommy
Nice! A salt spreader on the back may be helpful as well. Great work!
I talked to my mom about this but she said salt hurts her dog's paws:confused:Quote:
A salt spreader on the back may be helpful as well
maybe sand spreader?
Tommy
That is really cool! Now you just need a wireless camera on the front so you can plow the drive way from the comfort of the living room couch! Your making me wish it snowed more where I live!
DB
darkback2Quote:
Now you just need a wireless camera
The Mule has a 3meg webcam that I'm working on, with the netbook wifi connected to the house
PC(laptop) and running a webcam there is a very large lag time in commands to the Mule, without the
cam running the lag is not present, working on that soon, most everything I'v worked on lately to
get ready for the snow was machination, wheels,weight,plow,weatherproofing.. etc..
As is I can sit at the kitchen table with my laptop so I can keep an eye on it at all times
Tommy
Quote:
Originally Posted by Tommy_T
If the webcam is loading the PC more than 80%, try adjusting the priority of the webcam process and your command/control process. Increase the priority of the process receiving/processing commands and/or decrease the priority of the webcam process.
Either way its still really cool. Great Job.
DB
jRaskellQuote:
If the webcam is loading the PC more than 80%
Is it that, or because everything is running through a single USB hub?
1) Analog Output for the drives, and digital I/Os (limit switches, and switching)
2) Phidgets 3/3/3 for feedback(digital compass, gyro, acc)
3) Phidgets High Speed Encoder card for feedback
4) Webcam
I now have a US Digital USB4 to replace the Analog Output, I/O and High Speed counter with a single unit
but have not install yet.
http://usdigital.com/products/interfaces/pc/usb/usb4/
Tommy
jRaskellQuote:
try adjusting the priority of the webcam process and your command/control process
You were right, seems by reducing the sampling rate of the gyro(was 10 msec, now 100 msec) the problem is gone(Sweet!, and Thanks!)
But, while doing the plowing in video below the Mule sheared a bolt that held the wheel hub to the drive
axle, causing one wheel to stop turning(what a drag). replaced single 1/4-20 bolt with two harden steel .25" dowel pins.
[ame="http://www.youtube.com/watch?v=ylph_YJkCoc"]YouTube - George_0003.wmv[/ame]
Tommy
Life is Sweet!
Today my mom got a chance to play with the Mule, she said she like it and would use it, once I fix the depth perception issue.
Shouldn't be too hard.
Tommy
Glad to see you're getting the kinks ironed out. That's a cool little remote plow you have there.
If I put a snorkel on the Mule, it could now be an ROV
Putting a camera up by the upper headlight facing down over the plowQuote:
once I fix the depth perception issue.
fixes the depth perception problem.
Tommy
You should be getting a lot of practice tonight !!
This blizzard should be a great test .
john
jdolecki, that storm spanked the mule.Quote:
This blizzard should be a great test .
need to add at least 300lb I'm thinking.
[ame="http://www.youtube.com/watch?v=Ks4YIh1Az2Q"]YouTube - george_0005.wmv[/ame]
Tommy
I like the view from the "Mule Cam"
What you need are tracks! After a search for Snow blower tracks this came up.
http://www.snowblowersdirect.com/Ima...0500/i829.html
They are made by Ariens.
You should call Ariens ask nicely and say you will put an Ariens sticker on the side. And they might give you a set.
I gottn many free thing just by making a phone call and explainning what im doing and offer to put there name on it.
nice project, i agree with jdolecki, tracks would be nice on there.Quote:
Originally Posted by jdolecki
very interesting link, i've thought about tracks for my project for a while, but now that i've gone 2wd not going back to tank steering.
Quote:
What you need are tracks!
I would also, if, I had to ever go outside to get the Mule unstuck, or if the Mule didn'tQuote:
i agree with jdolecki
have to start mowing grass again this summer.
tracks would do a lot of damage to the lawn.
While yes the Mule got spanked by that last snow storm, it did teach me a few things.
1) Need more weight. (added 140lb of sand to test how much weight is needed)
2) Theres only so much a 50" plow can do, a snow blower can deal with 5ft drifts.
I'v seen 24Vdc snow blows, but they are very small. I'd need a 40" electric snow blower.
the other option is plow when under 8", in last snow it would needed plowing every 2hrs.
Tommy
Didi you see this one? Came up on the Parallax fourms
http://www.youtube.com/watch_popup?v=tPg1ZMiC9pA
These have been given to me for inspiration
http://www.robotshop.com/blog/robopl...plow-robot-311
http://www.treehugger.com/files/2009...-snow-plow.php
http://dvice.com/archives/2007/02/ro...robot_uses.php
http://hackaday.com/2010/02/01/snow-blower-robot/
http://www.motherearthnews.com/Do-It...-Snowplow.aspx
http://conceptpop.com/radio-controll...otic-snow-plow
jdolecki, sweet peace of work, that Roboplow. But.Quote:
Didi you see this one?
Tommy
As the Mule gets heavier(added 200lb of sand as ballast) and the Mule gets farther away
from home (over 450ft), I get to thinking "what if", while I have programed it to stop if WiFi
is lost(ping the base Pc each second), and if the PC shuts down the drives do go into fault,
and the Mule has never runaway(yet this winter),as I start to venture farther it's harder to have that
warm&fuzzy feeling I love so much with all the what ifs.
So I added a remote Mule shutdown button.
I got a Cobra microTalk GMRS Walkie Talkie from Walmart that listed a 20 mile range(tested at 2 Miles
non-line of sight, Sweet!). I stopped at Staples and got one of them "Thats Easy" buttons (seemed cute)
which I wired to one of the Cobra's call buttons. From RadioShack I got a SPDT 5V micromini
relay and a 1000uf cap. the relay when energized sends the Mules drives into fault.
A long range remote warm and fuzzy feeling for under $50, is a sweet thing.
Tommy
Hi all, new here. Very good material, I like the Mule, it's cool and very advanced compared to my mower project. It's RC operated at present. I will be adding a camera and a Sabertooth 2x50 soon. I also plan to try to make my project a multitasting machine with autonomous operation. I've experimented with building my own motor driver but had too many problems blowing the mosfets. I will be looking @ the Ardupilot as it may be useful, anyway maybe I can post some useful info here.
Good job on the mule.
Peep this out tommy just got off craigslist. Friendlly Robotics Mowbot.
Will take the cover off this weekend and post more pictures.
Pabble, I also would like to try a 2X50, I did try a 2X25 only because everyone was out of the 2X50's,Quote:
Sabertooth 2x50 soon
but after burning up two of them, which they replaced at no cost(other then shipping) I stayed with
a P&G drive I had. any way sweet work on your lawn mower.
Sweet find jdolecki!, one of them would be hours of fun to play with. If I had one now(in the winter) I'mQuote:
Peep this out
sure I would run the perimeter wire around my living room to test it out.
like both of you my mind is turning to lawn mowing again(stopped at three different places looking
at reel type mowers) in fact I must have been thinking this winter was done teaching me things, but
just the other day we got a little snow(3 to 4") I sent the Mule out at 290lb without a thought, but
soon had to return home to add more weight(added 140lb) because the snow was so wet.
Tommy
Thanks,Quote:
Originally Posted by Tommy_T
Ebay has alot of reel mowers. Probably the gang style reel mower would be best since it is made to be towed. That's a good idea btw, I also will look into that style.
Have you had any experience with the Arduino and if so which do you prefer, the Arduino or the Phidget? I have some experience with the Arduino and I tend to like it, the price is very good compared to alot of microcontrollers out there.
My motor controller is due to be delivered tomorrow, I will be changing my sprockets out in order to speed it up a bit. I'm wanting a fast walk speed, currently it's a little too slow.
PabbleQuote:
I also will look into that style.
I'v used a standard rotary 24Vdc mower(Earthwise) on the Mule last fall, and
it was fast and simple to implement, but to get a +40" cut path I would need
about three of them which would increase the Mule's footprint too much, also
camera angles would need changing when going from snow plowing to mowing if
rotary type are used.
My hope is that three reel mowers could be mounted the same as the 50" snow
plow.
I found one of the units in picture below, it has a chain drive system for the blade
which would simplify motorizing(if needed, which I'm sure its going to)
I'm now testing a single 14" low cost reel mower.
With the wet ground now that most of the snow is gone, is an idea time to test
the Mule's 10" wide turf safe tires(without the chains) for lawn damage, and all
test so far are sweet, even while doing zero radius turns.
The Mule's on-board controller is an net-book PC, I have not tested any Arduino'sQuote:
Arduino or the Phidget?
yet. I do have a few Phidgets I'v been testing but have not found a place for yet
due to limitations of the units or technologies.
Tommy
Very good Tommy T.
I received my 2x50 motor controller the other day and I am very impressed with it so far.
I ordered a Mow Pro 21" reel mower and I'm hoping I have the power to pull it. I've never used one so I don't know alot about them. I will tow it behind my current setup and see how well it does. If all goes well then I will design a new chasis and go from there.
Tommy is your bot remotely controlled or is it working autonomously?
I will post pictures as soon as I get everything together which maybe a month from now.
The Mule has four current modes it can operate in.Quote:
Tommy is your bot remotely controlled or is it working autonomously?
1) Wifi networked to PC in house for remote control with network camera(3) feedback.
2) Bluetooth wireless keyboard(Palm sized) for direct control of on-board PC
3) Wired joystick as backup when all else fails.
4) Programmable cut path, I do it once with Wifi or Bluetooth and record feedback
values(Velocity, Yaw) every 20msec for playback.
I'm still testing for best localization tools.
in my head I see http://www.havahartwireless.com/stor...og-fence/5144g
as being a sweet tool.
Lowest cost option seems to be on-board web cams for locating fixed targets.
Tommy
Did anyone "master" the P&G drive controller?
I have been doing research on electric wheelchair controllers to modify for robotics projects. Information is really tight lipped!
Most all (at least newer) electric wheel chair controller use a protocol call "Multiple Master - Multiple Slave" (M3S). Google it and you will find that the controller has a lot of safety features built in, including joystick and command validations. The best idea is to hack the joystick and mimic commands or position control assoicated with the brand of wheelchair/controller.
Let's keep in touch!
Thanks!
maleche, I'm using the P&G VSI speed controller on the mule now, notQuote:
Did anyone "master" the P&G drive controller?
sure about the master part because I have not over come it's programed
acceleration/deceleration profiles. But I do like the drive, lots of safety
back ups.
Tommy
Here are a couple of pics. I tried the reel and it works great, does a good job on the lawn. I also attached a camera and transmitter so I can control it while sitting in my shop. The receiver is attached to 36" HDTV. There is a draw back in that I did suffer some motion sickness :( I will try to take some photos of what it looks like on TV. I have a dialup connection so uploading a video is out of the question. Maybe I can go to a coffee shop and upload there. All works well, I will work on a new design now and concentrate on autonomous operation. Keep in touch, don't let the thread die.
Pabble, have you any idea how your going to deal with localization yet?Quote:
concentrate on autonomous operation.
While I'm sure winter has not finished teaching or entertaining me yet I also have
been doing some mower testing.
I got one of the three test reel mowers temperately mounted on the Mule.
Tommy
Cool setup Tommy.
Not alot of thought yet but maybe using laser rangefinders for x,y + optical interupter to stay within a certain range and maybe sonar for object avoidance. It's certainly not going to be easy.Quote:
Originally Posted by Tommy_T
I don't believe GPS will work in a small area. I honestly don't think I will be able to make it work reliably but I'm going to try. I give myself about a year on the task. Alot to learn. Maybe one can use GPS to find itself and work from there. I refuse to use any buried wire. I have 3 acres to mow :happy: Anyway this is just for fun anyway. What are your thoughts?
I'm thinking wireless dog fences that uses time of flight technology.Quote:
What are your thoughts?
But if these reel mowers could be used it may be possible to mow at night and use light
beacons(could be IR) and cameras for localization. last fall I tested a 24Vdc rotary mower
on the Mule but the noise was as much if not more then a gas engine, no way I could get
away with mowing at night with one or more of them.
Tommy