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csdude
05-28-2008, 02:06 PM
Does anyone know where I can find RC cars to build a robot car with ?
I am looking for a pickup style kind of truck, but a preferably more realistic than
the toy/transformer style kind of trucks I see when I search with google?

Ron

Adrenalynn
05-28-2008, 02:27 PM
I can't recommend it yet, but I have an RC truck on the way here right now, specifically to answer your question - I ordered it a few days ago off of eBay. New/Surplus. It's actually gihugic - I think it was 1/4 scale, but the one I found might be 1/6 scale, I remember it was like 30" long, and would do like 15mph on the flat. Anyway, there's a bunch of them on eBay. My goal was to present you a solution in a few days that was under $100 - but you pushed my hand. ;)

Let me see if I can find a picture. They had some others too... If you can wait a few days, I'll be able to report back.

Ahh, here we go. 28" long, 10" wide, 10" tall. Two speed gear-box. 7" real rubber tires. $65 shipped, new, old-stock. They apparently have more, as do other sellers, ranging from $45-$105.

I hesitate to post the search strategy or sellers until I confirm that they're useful.

I think it otherwise meets your criteria, see what you think?

http://www.jlrdesigns.com/4trc/hemi-rc-truck-1.jpg

http://www.jlrdesigns.com/4trc/hemi-rc-truck-2.jpg

csdude
05-28-2008, 02:59 PM
That looks awesome !! I think I can build a complete computercenter or cluster in the back of that thing. They look really neat too. (Heck I might even get two of them)

Adrenalynn
05-28-2008, 03:20 PM
Yeah, you could practically build a datacenter in there. ;)

I'm hoping to get a miniITX or at least a picoITX or two into it, a servo controller, and a couple A/D boards, maybe an Arduino or two for preprocessing. Add a video camera or two.

Sienna
05-28-2008, 10:56 PM
Hmm... looks like it cost $65 too... Doesn't look like something that will hold up well to student abuse.

Now, I don't know about everyone else, but I would look at a minimum for something like the Traxxas Stampede. I have the old one (http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXVK75**&P=7) which apparently was discontinued. However, I can vouch for their toughness.... any platform that can jump six feet in the air, repeatedly land on random sides, and keep doing it again and again... well, lets just say it can take what students can give out. I did have the larger Emaxx for a while too, and that was even tougher.

So I would urge you to take a look at the Stampede (http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNJJ0**&P=7) and other real R/C chassis.

Adrenalynn
05-28-2008, 11:18 PM
Thanks, Sienna. We went over the Stampede and Emaxx in another thread. Alas, he didn't like the size or look. We even chatted again about 'em today.

These ones I found are apparently pretty tough from all reviews elsewhere - kid-tough, which may be tougher than college-kid-tough. ;)

I'll keep everyone posted... Where ya' been hiding out? Missed you around here!

csdude
05-29-2008, 12:27 AM
Hmm... looks like it cost $65 too... Doesn't look like something that will hold up well to student abuse.

Now, I don't know about everyone else, but I would look at a minimum for something like the Traxxas Stampede. I have the old one (http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXVK75**&P=7) which apparently was discontinued. However, I can vouch for their toughness.... any platform that can jump six feet in the air, repeatedly land on random sides, and keep doing it again and again... well, lets just say it can take what students can give out. I did have the larger Emaxx for a while too, and that was even tougher.

So I would urge you to take a look at the Stampede (http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXNJJ0**&P=7) and other real R/C chassis.

Hi Sienna

The (this) robot is not going to be used in a class setting, but in a extracurricular 'interest group'.
So it's going to be 'their thing' and it probably won't be abused like regular equipment.

I like it because it looks realistic (real looking things potentially attract better future funding than transformer style projects). Also I discussed the model with Adrenalynn a bit. There is a lot of room available to cramp/hide a bunch of electronics and sensors etc in and still have a clean look.

Sienna
05-29-2008, 09:31 AM
Ok, sorry! I will butt out then. I must have missed the vehicle part in the last thread, sorry. Actually, no I wont*

My concerns aren't really about student abuse, but student error. No one is perfect, and hence we will make errors. Those errors could cause things to happen like the vehicle heading full speed into the wall. Its not intentional, just happens. (I have had my robot kick itself off the table a couple of times because of programming errors)


*Have you considered RC tanks? The only reason I ask is because making planning software for an Ackerman steered vehicle is a lot harder then making planning software for a differential / skid steered platform. The 1/24 scale tank I bought is a little too small for anything but an atmel, so I just placed a bid on a 1/12th scale tank :P I have even seen cheap tanks as large as 1/6th scale. These cheap tanks would be less rugged then the truck, but potentially easier to program.

csdude
05-29-2008, 10:50 AM
Ok, sorry! I will butt out then. I must have missed the vehicle part in the last thread, sorry. Actually, no I wont*

My concerns aren't really about student abuse, but student error. No one is perfect, and hence we will make errors. Those errors could cause things to happen like the vehicle heading full speed into the wall. Its not intentional, just happens. (I have had my robot kick itself off the table a couple of times because of programming errors)


*Have you considered RC tanks? The only reason I ask is because making planning software for an Ackerman steered vehicle is a lot harder then making planning software for a differential / skid steered platform. The 1/24 scale tank I bought is a little too small for anything but an atmel, so I just placed a bid on a 1/12th scale tank :P I have even seen cheap tanks as large as 1/6th scale. These cheap tanks would be less rugged then the truck, but potentially easier to program.

No no no, please do 'butt in', it's a forum I can use any opinions I can get. (Are you in education too ?)


I do understand that things might break because of student error etc. That is why I probably buy two vehicles, if superglue doesn't do the trick anymore I will still have parts from a crashed truck that can be used on the working one. Besides, teh vehicle itself is not that expensive compared to the electronics etc that go into it. Also, it is probably going to be a bit larger project than just 'make it work' (the 3 Asimov laws could/should be in there for example). Adrenalynn and I already discussed several ideas/options for kill switches.

Did I consider RC tanks. Uhm :) I work at a liberal arts college, somehow I think it might be easier for me to get money for another RC pickup truck/car because I/we/they crashed the first one we bought than getting funding to buy the an RC tank in the first place.
I can see that it might be easier to program it, but the project doesn't have to be easy. (But than again it also doesn't have to be mission impossible either.)

This extra curricular project is more like an 'ongoing extracurricular undergraduate research project' it is supposed to be not too easy. (of course they are undergraduate students, so it also doesn't need to qualify for being taken on the next mars expedition).

Sienna
05-30-2008, 11:46 AM
I can't see why tanks and liberal arts don't mix! :D :D

Seriously though, I wouln't worry about Asimov's laws. They are flawed from a human centric view. I think getting the truck to map and navigate a room will be enough of a challege.

You should have your students look at the DARPA Grand Challenge entries. I believe all of the competitors have to disclose how their entries work in order to enter. So, I think it should provide a wealth of information for your students.

The one other platform I might suggest...
The Tamiya 56307 (http://cgi.ebay.com/NEW-Tamiya-56307-1-14-RC-truck-Mercedes-Benz-1850L_W0QQitemZ300227835755QQihZ020QQcategoryZ1916 7QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) panel van. Not only do they look real, these things can haul. (I have a full semi, the trailer can take like 16 or so (full) cans of soda and the truck still runs fine!) What I am trying to say, these things have plenty of cargo space to hide gel cells, itx boards, what have you.

And its good that you and Andrenalynn are talking about e-stops and such already!

Adrenalynn
05-30-2008, 12:09 PM
I'm working on a very heavy very powerful 'bot right now, Sienna. It's intended to interact with people up-close-and-personal. ;)

Multiply redundant safety systems have to be designed in from the root on a 'bot like mine, imho. If a kid gets hit with a 400lb steel jagernaught out of control with a half dozen horsepower under it - well, that's a pretty significant setback. ;)

Actually, I expect the weight and HP will go up from initial estimates. I was originally using thin-walled steel tubing that just didn't fare well in simulation, so I went up to 1/8" wall square steel tubing. I've also doubled my batteries. It weighs in at just under 275lbs with only a frame, motors, motor controller, and batteries. The lifter isn't even started...

csdude
05-30-2008, 12:22 PM
I can't see why tanks and liberal arts don't mix! :D :D

Seriously though, I wouln't worry about Asimov's laws. They are flawed from a human centric view. I think getting the truck to map and navigate a room will be enough of a challege.

You should have your students look at the DARPA Grand Challenge entries. I believe all of the competitors have to disclose how their entries work in order to enter. So, I think it should provide a wealth of information for your students.

The one other platform I might suggest...
The Tamiya 56307 (http://cgi.ebay.com/NEW-Tamiya-56307-1-14-RC-truck-Mercedes-Benz-1850L_W0QQitemZ300227835755QQihZ020QQcategoryZ1916 7QQssPageNameZWDVWQQrdZ1QQcmdZViewItem) panel van. Not only do they look real, these things can haul. (I have a full semi, the trailer can take like 16 or so (full) cans of soda and the truck still runs fine!) What I am trying to say, these things have plenty of cargo space to hide gel cells, itx boards, what have you.

And its good that you and Andrenalynn are talking about e-stops and such already!

I am not too worried about Asimov's laws BUT I want them to build something that is different than 'yet another rover' that is cruising through the building. One of the things, not harming itself, could be interpreted as not crashing into walls other other objects, flying off stairs etc etc.

Hey that truck is pretty cool too, looks like we can put A LOT of stuff in that one. I must say I like the pickup though. However Andrenalynn already bought one of those pickups. I am waiting on her word to see if it is usable.

csdude
05-30-2008, 12:27 PM
I'm working on a very heavy very powerful 'bot right now, Sienna. It's intended to interact with people up-close-and-personal. ;)

Multiply redundant safety systems have to be designed in from the root on a 'bot like mine, imho. If a kid gets hit with a 400lb steel jagernaught out of control with a half dozen horsepower under it - well, that's a pretty significant setback. ;)

Actually, I expect the weight and HP will go up from initial estimates. I was originally using thin-walled steel tubing that just didn't fare well in simulation, so I went up to 1/8" wall square steel tubing. I've also doubled my batteries. It weighs in at just under 275lbs with only a frame, motors, motor controller, and batteries. The lifter isn't even started...

Oh and even a 20-25lbs truck 'barreling' into someone/something at 15Mph is probably an issue.

Adrenalynn
05-30-2008, 01:10 PM
Those look pretty cool! Check out this combination:

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290225486861&ssPageName=MERC_VI_RSCC_Pr12_PcY_BIN_Stores_IT&refitem=300227835755&itemcount=12&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget&_trksid=p284.m184&_trkparms=algo%3DDR%26its%3DS%252BI%252BSS%26itu%3 DISS%252BUCI%252BSI%26otn%3D12 (http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290225486861&ssPageName=MERC_VI_RSCC_Pr12_PcY_BIN_Stores_IT&refitem=300227835755&itemcount=12&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget&_trksid=p284.m184&_trkparms=algo%3DDR%26its%3DS%252BI%252BSS%26itu%3 DISS%252BUCI%252BSI%26otn%3D12)

http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290233162150&ssPageName=MERC_VI_RSCC_Pr12_PcY_BIN_Stores_IT&refitem=290225486861&itemcount=12&refwidgetloc=active_view_item&usedrule1=StoreCatToStoreCat&refwidgettype=cross_promot_widget&_trksid=p284.m184&_trkparms=algo%3DDR%26its%3DS%252BI%252BSS%26itu%3 DISS%252BUCI%252BSI%26otn%3D12

Build a whole datacenter in that thing. And imagine the complications of autonomously backing a trailer. ;)

[turns out that trailer is only 7" wide, and about the same length as the truck I ordered. So not all that large...]

http://www3.towerhobbies.com/cgi-bin/wti0001p?&I=LXGA18&P=FR

Adrenalynn
05-30-2008, 01:10 PM
Oh and even a 20-25lbs truck 'barreling' into someone/something at 15Mph is probably an issue.

It's great though if someone turns you down for funding... ;)

"Robots, ATTACK!"

csdude
05-30-2008, 03:02 PM
It's great though if someone turns you down for funding... ;)

"Robots, ATTACK!"

Yeah don't make me build that apache helicopter. *lol* with some
bottle rockets and that pattern recognition software you were
thinking about ....... *lol*

That tractor-trailer is kinda expensive, like $600. I actually saw an
augusta 1/10 helicopter for that money.

Adrenalynn
05-30-2008, 03:06 PM
I have a friend that got busted by the ATF for that. He built an RC rocket platform from a tank-driven truck and a screw drive lifter. He was firing off like 8 little B/C series rockets from it. No big deal, but someone freaked and they raided him. Seems they weren't happy with his safety interlock. They felt that with no real work it could fire horizontal, not just vertical. They fined him and made him disassemble it...

csdude
05-30-2008, 03:31 PM
I have a friend that got busted by the ATF for that. He built an RC rocket platform from a tank-driven truck and a screw drive lifter. He was firing off like 8 little B/C series rockets from it. No big deal, but someone freaked and they raided him. Seems they weren't happy with his safety interlock. They felt that with no real work it could fire horizontal, not just vertical. They fined him and made him disassemble it...

Whoops, ... with all that red tape you have to get really creative noways to have some sciency fun.

darkback2
06-02-2008, 06:45 PM
Ok...just a thought...what about something like lego NXT? If it gets crashed you just rebuild it.

LinuxGuy
06-02-2008, 08:31 PM
It's great though if someone turns you down for funding... ;)

"Robots, ATTACK!"
Heh heh there, my next robotics project is going to be a swarm.. :veryhappy::veryhappy: Those are the RSRs I have been working on designs for.. :happy:

8-Dale

csdude
06-03-2008, 09:51 AM
It's great though if someone turns you down for funding... ;)

"Robots, ATTACK!"




chicken and the egg problem here, if I don't have the funding I neither have the truck to do the barreling with. :)
But it could help with a possible stage 2 of the project.

csdude
06-03-2008, 09:54 AM
Ok...just a thought...what about something like lego NXT? If it gets crashed you just rebuild it.

We have some of that lego stuff here, it's cute... when you're 12.

The point is, in this project I want something that looks somewhat realistic. Using lego pretty much falls in the category 'transformers style".

csdude
06-03-2008, 09:55 AM
Heh heh there, my next robotics project is going to be a swarm.. :veryhappy::veryhappy: Those are the RSRs I have been working on designs for.. :happy:

8-Dale

That is why I want to build two. Why only build one if you can build two for twice the cost (no not mine, it's a movie quote).
Once I have two, they can hunt for funding in packs. (2 is the minimum for a pack, right ?)