A Design Implementation Process for Robotic Hand Synthesis

Abstract

The design of multi-fingered robotic hands can follow a kinematic synthesis approach, in which a trajectory or set of points and higher derivatives are defined for each fingertip. The output of the dimensional synthesis is a set of joint axes, effectively defining the basic kinematic structure of the hand. In the case of spatial motion, there seems to be a big gap between the results of the dimensional synthesis and a real and effective detailed design of the robotic hand, this being one of the reasons why synthesis is not regularly used in the design of robotic hands. This work aims to reduce the gap from kinematic synthesis to detailed, computer-aided design of robotic hands. In order to do so, the output of the dimensional synthesis is first used as the input of a link-based optimization process, aim to bring to reasonable values requirements such as link lengths, internal friction forces and obstacle avoidance, including self-intersection. The optimized results are automatically imported to a popular solid modeling software, creating reference geometry for parts, and joint axes and anchor points for the final hand assembly. At the same time, a database of hand parts is presented to the user to select and adapt in order to create a first realistic assembly of the robotic hand. The output of the process is a first detailed design of the robotic hand, which can be a good starting point for the designer to implement transmission and actuation in further stages.