Improved grasp robustness through variable transmission ratios in underactuated fingers

This paper investigates the possibility of increasing the robustness of underactuated grasping through the use of variable transmission ratios. We propose a 4-step procedure to investigate and improve the robustness of an underactuated finger on a fixed object. This procedure maximizes the robustness against random force disturbances to the maximum obtainable value under given circumstances. A simulation study is presented that analyzes the disturbance robustness, followed by an experimental study to confirm the effect. The variable transmission ratio is a promising means to increase grasp robustness and has great application potential.