Dynamic Finite Element Modeling and Simulation of Soft Robots

Abstract

Soft robots have become important members of the robot community with many potential applications owing to their unique flexibility and security embedded at the material level. An increasing number of researchers are interested in their designing, manufacturing, modeling, and control. However, the dynamic simulation of soft robots is difficult owing to their infinite degrees of freedom and nonlinear characteristics that are associated with soft materials and flexible geometric structures. In this study, a novel multi-flexible body dynamic modeling and simulation technique is introduced for soft robots. Various actuators for soft robots are modeled in a virtual environment, including soft cable-driven, spring actuation, and pneumatic driving. A pneumatic driving simulation was demonstrated by the bending modules with different materials. A cable-driven soft robot arm prototype and a cylindrical soft module actuated by shape memory alley springs inspired by an octopus were manufactured and used to validate the simulation model, and the experimental results demonstrated adequate accuracy. The proposed technique can be widely applied for the modeling and dynamic simulation of other soft robots, including hybrid actuated robots and rigid-flexible coupling robots. This study also provides a fundamental framework for simulating soft mobile robots and soft manipulators in contact with the environment.

Assessing an Energy-Based Control for the Soft Inverted Pendulum in Hamiltonian Form

“…Future work will be devoted to extending the proposed energy-based controller to multiple models (and robots) [18]- [20], trajectory tracking problems, and experimental validation. Even if experimental validation remains a bottleneck for soft continuum robots, it was demonstrated that implementing actuation at the structure's tip enables good control in both regulation and tracking tasks [21].…”

Universally Grasping Objects with Granular—Tendon Finger: Principle and Design

“…Future investigations could explore the use of different granular particles, adjusting the volume of granular bags, and selecting stronger DC motors for picking up heavier loads. In this scenario, numerical estimations [ 55 , 56 , 57 ] are useful to investigate the deformation. The artificial skin [ 58 , 59 , 60 ] can be covered outside the robot hand for sensing and friendly interaction.…”

Design, Manufacturing, and Open-Loop Control of a Soft Pneumatic Arm

“…Its use has been widely implemented in soft robots [12,54]. In the case of pneumatic soft robots, the work of Ding [55]-which is, however, much smaller in size than PAUL-or Cangan [56], which uses previously presented SoPrA arm, stands out. The prob-lem they present, however, is the high computational cost required, which often makes their closed chain control unfeasible, unless reduced-order models are used [57].…”