microcontroller

[jshalcott]

ok, i'm confused. my robot is going r/c controlled, not by itself. so do i need a microcontroller.

[dunk]

nope.
you are making a radio controlled vehicle so there is probably no need for a microcontroller.

dunk.

[JesseWelling]

That could depend....does he want a 3 wheel omni bot with x and y inputs? You could do this with pure analog electornics but I don't think it would be fun.

Describe the operation and design of your robot and then we may know more.

[jshalcott]

this is my first robot so i'm keeping it simple with the 2 wheel design using differental steering

[JesseWelling]

you should be fine without a microcontroller.

Just use a reciever and 2 modifited servos.

[Tsukubadaisei]

I cant get it. If you are going to use differential steering, then why don't you use 4 wheels? Usually people choose 2 wheels + caster combination because by doing so you don't need to worry about differential steering. If you place the 4 wheels, the 2 motors and the differential gear set with skill it will not only improve your control while steering but it will make your "robot" look better.

[ed1380]

More motors=more power usage, highers costs, etc
But if he wants to he could easily later add the other 2 motors

[jshalcott]

if i were going to go with the 4 wheel design, but still with differental steering. Could I just hook up a gear to the motor and and a gear on the back wheel, plus on the end of the wheel shaft have a sprocket and a chain that connects the front tire.

[ed1380]

Something like this with a longer wheel base would work http://www.societyofrobots.com/robot_asme.shtml

[Admin]

If you are going to use differential steering, then why don't you use 4 wheels?

a disadvantage would be much higher turning friction
tank steering is one step even further, with yet even higher turning friction losses . . .

[Ro-Bot-X]

I have built many drive train styles using Lego. It all depends on what kind of surface you are going to drive the robot. The car style robot (one motor to power the wheels and another to steer) is not very maneuverable sometimes. And the differential steering may take many forms:
- tank treads
- 4 wheels like a BobCat
- 2 wheels plus one or 2 casters
The differential steering is a lot faster in maneuvering but needs skills to do it right.
Here are some samples:
DiffSteeringCar

MiniSumoRobots