A G-FCON algorithm is designed for small-body surface sampling. It has a linearization component and a feedback component to enhance performance. The algorithm regulates the contact force between the tip of a robotic arm attached to a spacecraft and a surface during sampling. The control algorithm is insensitive to the surface properties, enabling it to maintain the right contact force for a wide range of surface compliance properties.

The objective of the algorithm is to bring the sampler in contact with the small body surface, and maintain a desired contact force for a prescribed duration of time for sampling. Once the sampling period is over, the control algorithm guides the spacecraft safely away from the surface.

This work was done by Behçet Açikmeşe, Marco B. Quadrelli, and Linh Phan of Caltech for NASA’s Jet Propulsion Laboratory.

The software used in this innovation is available for commercial licensing. Please contact Karina Edmonds of the California Institute of Technology at (626) 395-2322. Refer to NPO-44377.