Ours is also an arm with three sections: the long one, the short one, and the gripper
(with Points Of Articulation #1,#2, and #3 down the arm). We seemed to have the torque issue fixed with an adjustable spring and pulley system, and then the chaining started pulling our window motors apart due to the forces involved in braking the arm during a fall
. Hopefully we'll be able to resolve that issue and actually make a gripper by competition (the one I had made was much too heavy, 5.5 ibs at the end of a 4ish foot arm).