Robotic Project help

sterance42

Hey i am a highschool student with a lot of programming backround, but little engineering backround. I plan on doing a science project that is basically a giant rc car, except it does not have to be remote controlled.

In further detail, i'm making a robotic wheelchair that would run off my computer.

The thing i need to know is what kind of motors do i need, and how do i connect them onto my computer?

if you can help me even in the leastr i would be much obliged.

Franklin

What is your budget? How much weight does it need to carry? you would use some form of motor controller to power the motors. you will need to write a program on the PC to do what you want and communicate to the controller(s). If you can supply more info I could get more specific.

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
- Stephen

W9GFO

If you need motors for a robotic wheelchair, start with an electric wheelchair! Look on craigslist for "wheel chair", "wheelchair", "power chair" and "powerchair". People sell them for $50 up to $5,000, sometimes they just give them away.

I have two fully functioning chairs, the big kind, not the little three wheel scooter things. One is a Jazzy 1101, the other an Invacare Arrow Storm. They both have linear actuators for reclining, the Arrow has three! I paid $100 for the Jazzy but the Arrow was free. The Jazzy is nice because the entire chair assembly lifts off the base after removing just four pins. What's left is a nice, poweful, heavy duty, outdoor robotics platform.

Rich H

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
The Simple Servo Tester, a kit from Gadget Gangster.

IRobot2

Sterance42,


A few years back when I was in high school, I had a project very similar to yours that I wanted to demonstrate in the local science fair. My goal was to make a wheelchair that would go from point to point to give somewhat of a "guided tour" of say a museum. At each point the unit would stop and wait for a command to go to the next spot, or could return the the previous spot.

To the point: I was able to get the local newspaper to cover the project and say a little bit about what I was trying to accomplish. I mentioned that I was looking for local sponsors to help fund this adventure and would display their business or what have you on the project when completed. Turned out there was a local surgical appliance store that was kind enough to donate a refurbished "Rascal" type wheelchair/mobile device. Without that I would have spent months trying to develop and build a frame that could handle that kind of payload. The project turned out really well and the next year I striped it down and took a swing at making a robotic mower (which I am still working on).

So my advice is to try and get some sponsors to help you out either financially or even with time and tools (maybe a local machine shop). You might have to show a little promise (drawings, example code, project descriptions) to show them you are serious and have a good chance at following through with your project. Your surrounding community (online or where you live) will almost always be your biggest help. Just remember to make sure you really thank the people that help you and try and pay it forward in the future.

Err, sorry for getting off topic with your post, but I figured that might help you out a little. As for what motors you need and how to hook them up, follow what Rich said. Some times its best not to reinvent the wheel. If you are building a wheel chair type device... start with a wheel chair and see what that does for you. If you can not get one physically, I know many of the parts are listed on the sites of the manufactures that build them. As far as how to hook them up, I would highly suggest making a small table top model and get it working first. (There are many free parallax downloads with tutorials and such that will get you going.) I did A mock up with a BOE bot after chasing a 150lb wheelchair across my front yard.... Not Fun let me tell you....

▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
Alex Burke
"It is not how smart you are rather, it is how you are smart." -Jon Campbell

Post Edited (IRobot2) : 3/22/2010 8:54:34 PM GMT

sterance42

I already have the wheelchair, and my dad works for the sewage authority so i have use of a really great workshop that i can fabricate the frame from. The school has allowed me to use around $1000 to buy Motors with. I would probably put out of my pocket for the battery or the interface. I have been searching for an electric wheelchair. but i could only find a regular wheelchair. I can easily do the project, i just need to know how to run a motor from my computer. All the resources i have found are way too advanced for me.

thank you for all the feedback, this info is very helpful

Desslok

I haven't done this myslef but have researched. I had a friend that worked at Industrial Liquidators, a place that salvaged parts from things like wheelchairs, and sold motors and controllers. I'm guessing you will want some type of PMC motor controller:
Something like the one on htis page, this just happens to ba ll they have in stock at the moment, there may be this type of place where you live:
http://www.industrialliquidators.com/wesell/evwarrior.html

And this site has some circuit descriptions:

http://www.educypedia.be/electronics/circuitsmotorcontrol.htm