We have developed a compact and lightweight high-stretch ratio arm that does not interfere with crops that can be used in SynecocultureTM. This arm has pitch axis rotation by parallel drive of convex. Convex geometry was considered for an arm structure that meets the required specifications furthermore, the accuracy of arm movement position and angle control was verified. Consequently, the developed arm has a 60% higher expansion/contraction ratio than the existing arm and has achieved a significant reduction in size and weight while maintaining the withstand load.
