Contractile Performance and Controllability of Insect Muscle-Powered Bioactuator with Different Stimulation Strategies for Soft Robotics

Abstract

This article describes contractile performance and controllability using different stimulation strategies of a bioactuator made from dorsal vessel (DV) tissue harvested from an insect (final stage moth larva). This insect tissue is an excellent bioactuator because of its high robustness; an accurate adjustment of culturing conditions such as temperature and pH necessary for culturing mammalian living tissues and cells is unnecessary for the DV tissue. There are no reports that measure contractile force of the DV tissue directly or measure response of the DV tissue when stimulated by different strategies systematically. To this aim, a force measurement system, which can measure contractile force directly and allows adjustment for the DV tissue length, was constructed, and the contractile properties of the DV tissue when stimulated by tensile, thermal, electrical, and chemical (crustacean cardioactive peptide [CCAP]) stimulations were evaluated with a force transducer. It was found that the tensile response could control contractile force. The thermal response could tune the contractile force and contractile frequency and there was no thermal damage up to 35°C. The electrical stimulation could control contractile force. The CCAP chemical stimulation could control contractile frequency; the CCAP effective concentration was 10−6 M. It was concluded that the contractile properties of the DV tissue could be controlled using different stimulation strategies.