Driving torque model of the bionic soft arm’s hyperelastic bellows

ABSTRACT

The technology of soft continuum robots represents an advance in the field of robotics to benefit a wide range of industries such as healthcare, manufacturing or environmental exploration. Soft continuum robots can be driven pneumatically by bellows as the soft continuum manipulator presented in this article. A driving torque model of the bellows considering hyperelastic material properties, friction and restoring torques is derived, whose purpose is suitability for model-based control design and subsequent trajectory generation. Hence, the driving torque model must be real-time capable. This is realized by an iterative algorithm calculating the bellows’ torque transmission by assuming a two-dimensional no-slip membrane contact. Nonlinear strain behaviours and hysteresis effects of the bellows are considered by the Ogden material model. The driving torque model’s performance is validated experimentally by measuring the external torques of the bellows.

KEYWORDS:

• Soft robotics
• hyperelastic bellows
• dynamic actuator model

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work was supported by German Research Foundation (Deutsche Forschungsgemeinschaft, DFG) under grant no. SA 847/20-2.