[dtengineering]

Closing the loop... either with encoders on each wheel, or a gyro, or some other form of control... is necessary to enable the robot to travel in a straight line.

A good mecanum drive is much more challenging than a good tank drive. Read carefully the many threads that have discussed the topic, and then go for it. Very few people have ever seen mecanum wheels in action... and they are usually very impressed by what they can do.

Jason