End Effector Design and Fabrication for Multi-Surface Adhesion
Mentor:Aaron Parness, Principal Investigator in the Robotic Hardware Systems Group, Stanford University/ NASA JPL
There is no reliable way to non-destructively grip the exterior surface of large objects in space, since the earth orbit environment is unique in composition. Traditional methods which implement suction, magnetism, and wet adhesion (glue) are ineffective or impractical. Work was done to design an end effector that can adhere to the unprepared surface of objects with large radii of curvature and varied surface roughnesses. The design constraints also mandate that the mechanism must function in an environment with 3.2x10-2 Pa of ambient pressure at near zero gravity and it must have negligible engagement and detachment forces. Such adhesion is achieved through van der Waals forces, by utilizing a dry and unidirectional synthetic skin that was designed to imitate the climbing physics of Geckos. When loaded to 12kPa in its preferred shear direction, the current mechanism can adhere to a geometrically flat plate with a surface roughness of .0015mm, and support 2kPa of normal load. This is approximately 80% of the ideal adhesion characteristics of the skin alone. Final results will be presented. Future work will include sensor integration and material selection, for operation at low earth orbit temperatures of 175 degrees Kelvin.