A kind of 2-DOF armature apparatus that allows both driving motors to be placed on a solid base.
- Take two bars. of equal length and lay them parallel to each other.
- Attach one bar to a drive motor.
- At the end where the motor is attached, run a second bar, from the undriven bar to a second drive motor, whose drive axis is identical to the first.
- At the other end, attach a long linkage that is connected to the ends of both bars.
By now, you should have ended up with four bars connected in the shape of a
parallelogram, except that one
vertex is connected to two motors, and the opposite side has a long extension that can be driven:
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^two motors on the same axis
The
advantage of this design is that it allows you to mount
powerful motors, and not worry about wasting energy
flinging one of them around on the end of a rod. The disadvantages are that the linkage as a whole is somewhat
flimsy, and the
rotational inertia of the first arm is effectively
doubled.