In the past few weeks I have been working on taking over some of Pooja's work as she is not present this quarter. I have read a few papers on SCP actuators, how they work and how they can be produced. I experimented myself by making a few actuators in the lab using the setup created by the other lab members. However, I found the process very repetitive and time consuming. During the coiling process one has to use a finger to prevent the weight from rotating as the thread is coiled. During the annealing process one has to stand by the power supply and press the on/off button every 30s for 20 minutes. The latter was something that should be easy to automate. I built a switch circuit using a microcontroller and a MOSFET that would allow a user to set the number and duration of heating cycles and then just let it do its thing. This was already a major upgrade over the old system. The next step in further improving the system would be to operate both the coiling part and the annealing part with one microcontroller and add buttons that would allow the user to have total control over the process (start/stop coiling button, start/stop annealing button). The ultimate goal would be to have a system that can take a cone of conductive yarn and automatically build a SCP actuator based on the user's needs.
Last week I also attended a talk by Professor Majidi from Carnegie Mellon. He talked extensively on new efforts to create soft robots, from internal circuitry, to structural strength and actuation. What I found most interesting was the use of liquid metal alloys (such as Gallium Nickel) droplets trapped in rubber to create conductive soft material. Liquid metals could also be used to improve cooling performance of circuits embedded within insulating material without significantly impacting its "softness". He also showed a project in his lab which uses memory alloys to actuate a soft robot.