Autonomous science target touchability evaluation: A fuzzy logic-based approach

Currently, for Mars science target selection, the task of determining whether or not it is possible for a robot arm to touch a target is accomplished by human operators and scientists on Earth. The development of useful on-board autonomous touchability techniques would greatly reduce human intervention. It would be advantageous if the rover could evaluate autonomously whether the robot arm would be able to place an instrument against an identified science target. In this paper we propose a new approach to the problem of autonomous science target touchability evaluation. We assess the touchability of a potential science target in terms of its size (the number of pixels of the science target in the image), SV (the science value of the science target), distance (the reachable distance of a robot arm), and orientation (the angular regions of the arm’s shoulder azimuth). In particular, the plane in front of the arm is divided into a number of partitions, which are ranked with the different touchability levels by the use of a fuzzy rule-based system. Simulations on the rank of science object touchability are carried out, via software and hardware implementation. Based on the real data gathered from the cameras and the Schunk arm experimental results successfully verify the validity of the proposed approach.