
Becoming Mobile • Chapter 8 137
the same direction, while the other is geared to rotate the other input axles in
opposite directions.To operate a dual differential drive, you will normally use just
one of the motors, keeping the other braked.
In Figure 8.9, you see the same assembly as in Figure 8.8, but without motors.
When motor 1 rotates the 40t gear A, and motor 2 keeps B braked, motion gets
transmitted along the dotted line path in the picture, the two differentials rotate in
sync and the robot goes straight. On the other hand, keeping motor 1 off and
consequently A braked, and operating motor 2 to rotate B will make the motion
transfer along the ...