Soft continuum manipulators represent a growing field in robotics originally inspired by boneless biological appendages. Elephant trunks and octopus arms, for example, provide dexterous and advanced morphological movements that have influenced the design of robot manipulators for numerous applications. Use of non-rigid materials improves safety of human-robot interaction while preserving versatility in unstructured environments. For daily living tasks that involve grabbing and holding objects, individuals with limited hand or arm functionality can be assisted by a wearable, soft continuum robotic system. The utility of such a system depends highly on the range of object weights, volumes, textures, and shapes that can be effectively handled. Therefore, a hybrid design with finger-like end-effectors can enhance object manipulation capabilities.
Researchers at Arizona State University have developed two soft grippers for attachment onto the end of a soft continuum manipulator. One design features a single bio-inspired continuum gripper and the other an opposing multi-fingered gripper. The grippers are composed of soft actuators made with high-strength inflatable fabrics, offering a range of compliance, lightweight designs, and high strength-to-weight ratios. Their motion is achieved through selective distributed bending, meaning that joints can be formed along any point over the length of the gripper. In addition, the introduction of a rotational wrist joint converts bending motion of a soft actuator array to rotational motion, adding a new dimension of control to the system.
• Soft continuum manipulator systems
• Robotic assistance for daily living tasks
Benefits and Advantages
• Inflatable gripper and joint designs extend object-handling capabilities of continuum manipulators
• Use of soft, lightweight materials support wearability and close human applications
• Highly modular, cost-effective, and compressible construction allows for rapid replacement and/or storage of grippers