A stated objective of the field soft robotics is the ability to interface with the human body. Traditionally, silicone materials have dominated the field of soft robotics. In order to shift to materials that are compatible within the body, developments must be made into biodegradable and biocompatible soft robotic actuators. A team of students, 7th through 11 graders at The Haverford School, an all-boys private school in Pennsylvania, developed “gummy” actuators which are biodegradable, edible, and tasty. The goal was to create actuators that can be both sold as an interactive candy product for children and also inform the design of implantable, biodegradable soft robotic devices. First, commercially available gelatin-based candies were recast into pneumatic actuators utilizing molds found on the Soft Robotics Toolkit. Edible robotic devices were pneumatically actuated repeatedly (up to n=8 actuations) using a 150 psi power inflator. To improve upon the properties of actuators formed from commercially available candy, a novel gelatin-based formulation, termed the “FORDmula” was also developed and used to create functional actuators. To investigate the mechanics and functionality of the recast gummy material and the FORDmula, compression testing and biodegradation studies were performed. Mechanical compression tests showed that recast gummy materials had similar properties to commercially available candies and at low strain had similar behavior to traditional silicone materials. Degradation studies showed that actuation was possible with the first 15 minutes in a biologically relevant solution followed by complete dissolution of the actuator afterwards. A taste test with elementary aged peers demonstrated the fun, edible, and educational appeal of the candy actuators. Their development was an entry and winning submission in the High School Division of the Soft Robotics Toolkit Design Competition hosted by Harvard University. Demonstration of edible soft robotic actuators created by middle and high school aged students shows the applicability of the Soft Robotics Toolkit for secondary STEM education. It also presents the opportunity for the application of soft robotics in the culinary field as well as the development of biodegradable actuators for biomedical applications.
You can see the students submission here: https://vimeo.com/220906510
And their contribution to the soft robotics toolkit here: https://softroboticstoolkit.com/edible-actuators
Keywords:Composite elastomers, Hybrid elastomers, Soft actuators, Soft electronics, Soft robotics, Soft sensors