Fig. 5: Interactive teaching kinematics control method for the soft manipulator.
From: Touchless interactive teaching of soft robots through flexible bimodal sensory interfaces
a A schematic view of the soft manipulator, consisting of three segments, each containing three chambers that actuate pneumatically. The FBSS is placed on a flexible, arc-shaped patch with three magnets on the back. Small magnets were also placed around the bottom of each segment of the soft manipulator, so the position of the FBSS can be quickly shifted. b Geometric functions in the bending segment, where φi is the segment deflection angle around the z-axis; θi is the segment curvature angle around the y-axis; ri is the segment curvature radius; li is the arc length of the segment; rij is the curvature radius of each actuator; lij is the arc length of each actuator. c The actuation, joint, and configuration spaces and mapping between them, define the inverse kinematics (finv). d The closed-loop control framework for interactive teaching, where V represents the measured voltage of the FBSS, Sout is the normalized voltage signal, θh is the calculated step length, and pij represents the pneumatic pressure of each soft actuator. e The mapping of the step length θh and normalized voltage signal Sout. f Interactive teaching experimental results: execution time and the position error of the soft manipulator as a function of step length. Box plots indicate median (middle line), 25th, 75th percentile (box) and maximum and minimum values (whiskers) as well as average values (single points). g The simulated workspace of the soft manipulator with interactive teaching. Error bars represent standard deviation, n = 5 independent replicates.
