A novel optimization method to simultaneously design the structure and dynamic motion of soft robots

A study conducted by Changyoung Yuhn et al. was published in the Computer Methods in Applied Mechanics and Engineering.

Soft robots made of materials, such as rubber, have gained increasing attention in recent years due to their gentle touch and flexibility for adapting to changes in the surrounding environment. Topology optimization has been widely employed to obtain the optimal structure of objects using a purely mathematical approach, without relying on preconceptions. However, the application of this method for the structural design of flexible and actively moving objects has faced challenges in simulations, especially for the simultaneous optimization of the structure and motion of the object. This study proposes 4D topology optimization for the simultaneous optimization of the structure and motion of soft robots. The structure, actuator placement, and time-varying actuation of soft robots are optimized by representing them as densities over the design domain in space (3D) and time (1D). The study demonstrated that the proposed method could successfully create soft robots that can move, rotate, and control their posture. The robots resembled living creatures, which is realized by skillfully moving complex structures, similar to body parts, such as legs. This innovation is promising for designing soft robots that are driven by air pressure, magnetic materials, or muscle cells and have potential applications in the medical and industrial fields.