Different kinds of grippers are used in today’s automation process to pick up, move, rotate, and handle objects with different sizes, materials, and shapes. With today’s tendency to flexibilize automation processes, the need for universal grippers is improving. In conventional automation process, magnetic grippers for handling ferrous materials; Pneumatic grippers for fast handling of light objects; and many other kinds of grippers are specialized to handle objects with certain size, shape, material, and weight. These mentioned methods of handling objects work great for structured automation environments, but they fail when it comes to unstructured automation environment.Photo Credit
Soft materials have revolutionized soft grippers by introducing and developing soft grippers. Soft grippers are considered for applications with high degree of freedom to handle objects of varying size, shape, materials, and even delicate objects. The Nature introduced good examples of soft grippers such as lizard tongues, octopus arms, and elephant trunks that can work with highly degree of freedom consists of bending, extending, and twisting. Pneumatic soft grippers are the simplest form of soft actuators with single air pressure input and unsymmetrical stiffness actuators.
In Pneumatic soft grippers, Increasing the input pressure of the actuator results in bending in opposite direction of softer wall. People of Soft Robotics Company are industrializing soft robotic grippers that can manipulate items of varying size, shape and weight with a single device. Their ultimate goal is to help vegetable market with fresh cutting of fruits, decrease losses due to labor shortages, and help distribution centers with picking objects.
A shortcoming with the proposed mechanism of pneumatic soft grippers is that actuators on the gripper can only bend in predefined direction, which limits the functionality of the gripper. Moreover, this model of gripper fails to pick up and handle flat surfaces and rotate objects. To address this problem, I am helping my peers at Shan Research Group to improve the functionality of soft grippers through adding rigidity tunable tendon to control the motion of soft fingers attached to soft gripper. Please check my next post for more information about our improved model as well as other different methods of manufacturing soft grippers.