Omni-Directional Vehicles

Omni-directional vehicles have a significant advantage over conventional vehicles with car-like Ackermann steering or the differential drive using two independent wheel motors as in Eve and many of our driving robots. Omni-directional driving allows going forward/backward, but also sideways left/right and turning on the spot. This is especially helpful when having to maneuver in a tight environment such as a factory floor.

The EyeBot controller drives 4 independent wheels on the omnidirectional robots Omni-1, Omni-2 and Omni-3. These robots use the "Mecanum" wheel design with free rollers around the wheel circumference. Each robot can drive in any direction, i.e. forward/backward, sideways, at an angle, and turn on the spot. The robots are using the EyeBot controller with an add-on module with two additional drivers. For details see the book "Embedded Robotics".


Omni-Wheelchair Omni-1 Omni-2
This uses the conventional Mecanum wheel used in Omni-1, and the suspension system in Omni-2, to create a large scale omni-directional robot that is used as a wheelchair. The conventional Mecanum wheel design with the rollers held at the sides. This is a disadvantage when driving on non-smooth surfaces, because the rims will make contact with the surface. A new Mecanum wheel design where the rollers are held in the middle. This gives an advantage when driving on general surfaces, together with a suspension system that suspends every wheel individually.

Vehicle Specific Settings

TPU  0     front right motor speed
TPU  1     front left  motor speed
TPU  2-3   front left  shaft encoder
TPU  4-5   front right shaft encoder

TPU  6     back right motor speed
TPU  7     back left  motor speed
TPU  8-9   back right shaft encoder
TPU 10-11  back left  shaft encoder
DO   0,1   front left  motor direction
DO   2,3   front right motor direction
DO   -,5   back  right motor direction
DO   6,-   back  left  motor direction

Thomas Bräunl