ToRoS is a topology-optimization approach for designing robotic skins made of stretchable fabric structured with 3D-printed reinforcements. It enable to quickly design and build soft pneumatic robots that can move and deform in desired ways.
Fig. 1. Automated design of a pneumatic gripper using our method. Our method produces an optimized reinforcement pattern such that the inflated shape closely approximates the target deformation.
Soft robotics offers unique advantages in manipulating fragile or deformable objects, human-robot interaction, and exploring inaccessible terrain. However, designing soft robots that produce large, targeted deformations is challenging. In this paper, we propose a new methodology for designing soft robots that combines optimization-based design with a simple and cost-efficient manufacturing process. Our approach is centered around the concept of robotic skins—thin fabrics with 3D-printed reinforcement patterns that augment and control plain silicone actuators. By decoupling shape control and actuation, our approach enables a simpler and cost-efficient manufacturing process. Unlike previous methods that rely on empirical design heuristics for generating desired deformations, our approach automatically discovers complex reinforcement patterns without any need for domain knowledge or human intervention. This is achieved by casting reinforcement design as a nonlinear constrained optimization problem and using a novel, three-field topology optimization approach tailored fabrics with 3D-printed reinforcements. We demonstrate the potential of our approach by designing soft robotic actuators capable of various motions, such as bending, contraction, twist, and combinations thereof. We also demonstrate applications of our robotic skins to robotic grasping with a soft three-finger gripper and locomotion tasks for a soft quadrupedal robot.
Fig. 2. Pneumatic walker. Our method generates a design that enables the inflated robot to stand and to move forward at approximately 2.5cm per cycle.
This paper will be presented at SIGGRAPH Asia on 13 December 2023 at Sydney in Australia.
More photos and videos will be posted after the conferences.
 Juan Sebastian Montes, Ronan Hinchet, Stelian Coros, and Bernhard Thomaszewski. "ToRoS: A Topology Optimization Approach for Designing Robotic Skins," in SIGGRAPH Asia 2023