Main Site Documentation

Ever thought of using a "pro" RC car as a robot chassis?


#1

Has anyone here ever though of using a “pro” RC car (as in, costs $200+ and goes 35+MPH) as a robot chassis?

The way I see it, for less than $100, you could get an RC car kit with everything but the transmitter and receiver.

I would assume that an RC car/plane/boat ESC probably takes the exact same pulse wave that is fed to a regular servo, and if that’s the case, my servo driver could be used to talk to it.

Not only would you have a fast, durable chassis, but you could also control it with hardly any effort at all, since you would only need to talk to two servos.


#2

One of the groups I work with at the university has built several robots on RC truck chassis. They have had some issues accounting for the inherent slip with Ackerman steering (car type steering) and keeping track of the wheel rotation (and accounting for wheel slip). It can give you a nice platform to work from though.


#3

I have thought about this too. Even with a cheap chassis you could build a nice robot with less efford.

I do not know how the electronics work on such a RC car, but I guess it should not be hard… :slight_smile:


#4

The electronics are very simple since the the speed controller uses the same communication protocol as a servo. It would require hardly any effort to connect the FEZ, both electrically and in code.


#5

Opps, I didn’t see Jeff’s reply…

I take it that would be that sort of warehouse building I saw on my campus tour last year? I think my tour guide said they would be expanding that, too…

I never thought of any issues with slipping. I might research this a little more then. Does that group have a webpage somewhere?


#6

I suspect the warehouse type building you saw was the Student Design Center, that is where the Solar Car, Mini Baja, Etc, Etc teams build their projects. They are in the planning processes of a new shop facility now. (For everyone that does not know what Chris and I are referring to, we are talking about Missouri S&T.)

The professors name is Sarangapani. I did a quick search on the university website but could not locate specific information about the various mobile robot projects. He has a ton of patents and papers so it is hard searching through everything that comes back when you search on his name.

If you do some digging on various types of robots locomotion platforms you’ll find there are benefits and drawbacks to each design. Here is a PowerPoint of the various common types of robot locomotion I just found: http://www-ee.ccny.cuny.edu/www/web/jxiao/Design-Locomotion.ppt


#7

Yeah, “Student Design Center” sounds right.

Thanks for the powerpoint pres. I read through it and saw a lot of valuable information.

I think I’m going to look around for a good, cheap RC car. I’ll post back here if I find something that looks good. The biggest thing is that there needs to be enough room on top to mount electronics, and the RX/ESC must be separate boxes, so that rules out most smaller cars.

It looks like most of the car kits are higher end models, so they will be really expensive even without the drive electronics (ESC, steering servo, motor, battery, etc).


#8

I have a HPI blitz i converted that can run both remote and sensor based. I started coding it to learn the short course track at the local RC course. Its run by a Amtel chip so not fez based. I put it away for some reason not quite sure. Maybe cause i have way to many robots.


#9

Hmm, well, I was thinking about using a Traxxas Rustler of some sort. Plenty of room onboard for electronics, and if I wanted to, I could probably layup a flat fiberglass top to cover with velcro for all of the electronics, breadboards, servo mounts, etc.

I don’t even need anything fancy. As long as it has a typical ESC and steering servo, I’m set. Any other car suggestions?


#10

Just make sure you dont raise its center of gravity to high when traveling at higher speeds it will matter.


#11

I don’t think I’d run it much past 6-10MPH. Even that kind of speed is probably too fast, so I don’t think I’d have to worry about where the CG is.

Still trying find other cars…


#12

well is you are looking for ultra stable and speed it not the biggest thing look at rock crawlers. I have a loki that wont stop.


#13

What do you guys think of the Duratrax Evader?

http://www.duratrax.com/cars/dtxd29-evader-ext/dtxd29-chassis.html

I like how the ESC is up on that post. More space for electronics on the bed.

One of my concerns is that chassis looks to be made of cheap plastic. Is that the norm for these cars?

The Evader is the cheapest option I have looked at so far; you can get it RTR as low at $120


#14

look like it has real good space to work with in the chassis. The style of plastic looks pretty normal for a RC car.


#15

I looked further into it, and I don’t really like the Evader too much. For one, it doesn’t appear to be the fastest, only 20MPH. I was looking for more like 25MPH, 35 would be GREAT. Also, the Evader doesn’t come with a batter and charger, so it isn’t really very RTR.

I still think a Ruslter or a Bandit is a better fit. Not as cheap, but sometimes it’s really worth paying a bit more. Whether that matters in a situation like this is up for debate, though.


#16

I saw this video on Youtube: http://www.youtube.com/watch?v=3aFwmMzm5wE&feature=related

…and it seems to say that this, in fact, a practical idea. I’m going to talk to a firend of mine, and I might order a car in the next two weeks or so…


#17

To bump this thread again, I found another car I like: http://www.horizonhobby.com/Products/Reviews.aspx?ProdID=ECX1000

I just took a look at one in person. It’s a nice car, but it looks like there would have to be a tray or something made to put the electronics on. There isn’t a ton of room for them on the chassis itself.

The big difference between this and Ruslter is that this is quite a bit cheaper and can be had for about $129 or $119 depending on where you look.


#18

I would go to walmart or any supper market and see what they have on clearance. You may find similar RC cars for much lower price.


#19

You could use plexi for the electronics mounting?


#20

I could do that, but the whole point of this project is to use a high powered hobby grade RC car to run a course in as little time as possible.

I was actually going to use a fiber glass layup, unless I can get something better designed.