Design, Modelling and Implementation of a Foldable Pneumatic Soft Manipulator

Soft manipulators, which are mainly used to conduct grasping and manipulation tasks, belong to a special category within soft robotics. Their unique characteristics, such as their light weight, foldable volume, and flexible movement, make them ideally suited for a range of spatial manipulation tasks. As such, this study presents the design and development method for a foldable soft manipulator. The soft manipulator comprises three pneumatic actuators and foldable straight arms, and can transfer its shape between the contracted and expanded states, making its volume foldable. According to this design, a relevant kinematic model for the soft manipulator is deduced. The shape deformation and workspace are numerically calculated and analysed. For verifying the prediction accuracy of the aforementioned model with no consideration of gravity effects, a soft manipulator prototype as well as the relevant air-floating devices have been proposed such that it can float on a marble platform. By limiting the motion control of the soft manipulator within the plane, the prediction accuracy of the proposed model is validated through the microgravity experiment. The foldable soft manipulator proposed in this study demonstrates a novel potential application of space manipulators.