Thanks for the interesting posting. I am not very familiar with the particular robots discussed, but they certainly sound interesting. Probably a bit too expensive to use for fun activities The explanation about the two types of brake service brought out an important consideration, which is brake energy dissipation. Holding-duty brakes don't need to absorb energy and dissipate heat, while stopping brakes must turn all of that kinetic energy into heat, and then safely get rid of it. That is really quite a large difference indeed. The first place I think of holding brakes is in an industrial robot, which must have good holding brakes for all six axis or else collapse in a tangled heap if the power fails. But they usually do it so perfectly that we don't hink about it. But they are vital in that application.
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