I'm a programmer and I'm working on a simple robot simulator. Of course, the most important part of this simulator, is the physical simulation of the robot. Unfortunately, I have a little knowledge about mechanics(only what I have taught in highschool and physics 1 in university).
You can see a simple model of robot in the picture. We have two wheels connected to motors (located on variable positions) and a wheel on the front(the white circle), for balancing. Every motor can apply an angular velocity to its wheel and cause a linear velocity on it (the angular velocity is known here, and can be controlled by the voltage applied to the motor).
Now, there are several questions:
1- Is it right to say "the motion of the robot can be described as a transitional motion of center of mass plus a rotational motion about that point?"
2- Are the forces applied to the system by wheels(their reaction, of course) relative to their velocity? Is this relativity linear?
3- How can I calculate the motion parameters? I think what I need is the way to calculate the linear velocity, the angular velocity, and some point to apply these velocities.
Thanks for your time!
UPDATE: From the answer by dear @Mike Dunlavey, I understood that when we have velocities of the wheels, then we do not have to do complex mechanical analysis, and angular and linear velocity of robot can be determined by some simple calculation. Also this velocities are not related to shape and mass of the robot's body, but it is related to velocities of the wheels and their distance, from each other.
Now, there is some remained questions. When left wheel has velocity of v1, right wheel has velocity of v2 and the distance between them is d:
1- How to determine linear and angular speed and its axis (center) of rotation? (The exact formula, plz.)
2- What happens if wheels are not vertically aligned?