robotic backhoe? crazy?

I have an old 1988 catapillar 426 backhoe, 4x4. It weighs about 16000lbs, but is not really *that* big. I don't use it for anything anymore, and so I was
wondering if it might be an interesting to convert it into a robot. Perhaps just remote control, but maybe have macros built in so it could perform repetive operations like digging a trench. Since I already have the major component (the working backhoe), I am thinking maybe it would not be too expensive to automate it? Air cylinders to actuate the brakes (they are somewhat mechanical....the foot pedals control a complex linkage to the rear differential, which contains a wet plate brake thing). The brakes actually do not work that well anyway :-). Steering could be as simple as a large gearmotor or something. The expensive part would be replacing the hydraulic spool valves with solinoid valves...that could run many $$$.
I have about 21 acres of very interesting mountain land to play on. I could be part of that exclusive club of 16000lb robotic backhoe owners...
Rick
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
oh, here is a pic of it:
http://www.skyko.com/backhoe/cat426.jpg
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
wrote:

http://www.badmovieplanet.com/3btheater/k/killdozer.html
Best regards, Spehro Pefhany
--
"it's the network..." "The Journey is the reward"
snipped-for-privacy@interlog.com Info for manufacturers: http://www.trexon.com
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

but
was
Two words: KILL SWITCH
Otherwise, sounds like eight tons of fun.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rather than replacing the spool valves etc, why not make something to pull/push the manual control levers ...
Dave

but
was
Perhaps
repetive
component (the

automate
mechanical....the
contains a

:-).
expensive
valves...that
could be

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
rick wrote:

No, the expensive part would be liability insurance for operating an 8 ton robotic vehicle in an unprotected area (even your own land). Actually, if it went haywire and destroyed anything -- let alone hurt or killed somebody -- you'd probably be arrested.
You have to ask yourself why Caterpillar doesn't sell many robotic vehicles, even though they certainly have the R&D dollars to develop them. The answer is "lawyers."
-- Gordon Author: Constructing Robot Bases, Robot Builder's Sourcebook, Robot Builder's Bonanza
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Or Unions..
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I rather agree that operating a robotic backhoe in an unprotected area without extensive kill switch schemes would be unsafe and probably illegal.
Maybe it can't be done safely at all. I am not sure. I *think* I could design circuitry to kill the engine, with a 2nd system as a failsafe backup. A transponder could be wired up so if the backhoe goes out of its range, the engine is shut off. I was not so much thinking of operating it autonomously, as much as just by remote control, with macros. Its not like I am ever going to get around to this type of project anyway.
So, what do you think of the DARPA 200 mile race using multi ton humvees? I think that project is much more dangerous, and according to the sci american article, one team was running it without a hardware killswitch device (their killswitch failed twice, so they decided to continue their tests with just a software killswitch). Talk about unsafe!
Rick
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
rick wrote:

Not much. I think the whole thing is a crock, and the competitors (mostly from universities) are putting their schools/businesses are huge legal risk. God help a lost hiker and the slightly wayward robot... Well, we'll know in about a week.
Remember: Asimov was just kidding about the Three Laws of Robotics.
-- Gordon Author: Constructing Robot Bases, Robot Builder's Sourcebook, Robot Builder's Bonanza
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

without
design
autonomously, as

to
I think a backhoe project is perfect. There has already been significant research done in this.
Alot of the modern diesel engines have an electric solenoid in the injector pump that shuts fuel off. They are setup so that it requires current to keep the valve open. Even if the engines' injector pump lacks this (a 1988 backhoe might be a completely mechanical injector pump), you could put a simple solenoid valve in the fuel line running from the fuel tank to the injector pump.
I have some limited C, and have worked out some of the pseudo code for controlling a backhoe in soft soil. Realistically, my C is not strong enough to actually do the *real* programming for this, though.
I am convinced that this could be done, and in a cost/effective way. Major issues--safety. It needs to kill itself if machine wonders outside of it's area (I thought GPS was the most reliable way to set this up). It also needs to kill itself if a person comes close to the machine. Chatter--the best way I can think to describe this is you get an oscillation built up in the overall machine through movement of the components (via hydraulic actuation) which, when it happens, shakes the holy $h!t out of it and the operator. If you are running things slowly, probably not an issue. Controller--someone stated that it would be best to move the existing controls to actuate the valve body...I disagree. It needs to be controlled through solenoid valves for simplicity and robustness. I think they could be incorporated without interfering with or modify existing hydraulic valves. A definite advantage if you want to put everything back to the way it was.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
" robotic backhoe? crazy?"
Yes
Please post pictures!
Mike

but
was
Perhaps
repetive
component (the

automate
mechanical....the
contains a

:-).
expensive
valves...that
could be

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Actually your not crazy, the Japanese have beendoing it for many years now. They first used remote control construction equipment on the special mud slide channels they developed. No one wants to go work in a 100 yard wide 20 foot deep channel where a 60mph mud slide could come down on you at any time. Then there is work on volcanoes in Japan. The dangers of forest fire fighting is another popular subject too. Here in the US they have robotic street and concrete stripping machines that they use on highways and bridges. It's a nice thankless task that a robot can do very well. A google search can turn up interesting things like http://fire.nist.gov/bfrlpubs/build02/PDF/b02055.pdf
http://pica-pedra.planetaclix.pt/ROBOTS.pdf
http://www.newportpartnersllc.com/IRT_Construction_Robotics.html
This one shows a tantalizing glimpse of a robotic backhoe too. http://www.comp.lancs.ac.uk/engineering/research/mechatronics/mobile.html
http://www.csiro.au/index.asp?type=mediaRelease&id=MinerRobot&xml=relatedMediaReleases ;count0;start=0&style=mediaRelease
I haven't hit the magic google search word combination for findng the info on the Japansese remote control construction equipment they use to clear mud slide channels and volcanoes with, but it's out there someplace. Public TV used to run a TV program for time to time about these mud sides and they'd showalotof nice full sized construction equipment in Japan being used to clear the channels.

but
was
Perhaps
repetive
component (the

automate
mechanical....the
contains a

:-).
expensive
valves...that
could be

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Also look for the robot bulldozers Israel is using to flatten houses in areas where the locals tend to object to that sort of thing.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

info
mud
being
Check out Robotech Industries at this URL http://www.unbound-tech.com/unbound.htm
Also look at http://www.automatedmining.ca/about.html
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Rick, I was doodling out something like this, but it was the opposite in size. I have a pond I want to dig out, after draining it. I wanted to build a very SMALL backhoe or dragline that would move a very small amount of dirt/muck. But keep doing it 24 hours a day for a month or so.
Is THAT crazy??
--
Regards, Terry King ...In The Woods In Vermont
snipped-for-privacy@fredking.us
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I love the idea. A time-lapse video would be very interesting to watch.
How consistent is your muck? Any roots or rocks in it?
--
Guy Macon, Electronics Engineer & Project Manager for hire.
Remember Doc Brown from the _Back to the Future_ movies? Do you
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.