I feel a need to insert a ghetto design, so here goes. I'd use a four door hinges from a random door or hardware supply store. (long ones, not househole hinges.) Then get some sort of softish foam (wrestling matish) or, more ghetto, make small pillows. These would go on the ends of the hinges, which are controlled via servo, or some motor. So, the soft parts on the gripper allow the baton to be less slide prone and the hinges are very ghetto.
Don't feel like firing up MAX at this hour, so here is my ghetto rendering.
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Side (it wouldn't be so steep in real life)
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