Construction date: January 2019
Development Cost: ~500.00 dollars (in parts)
Time to build: One actuator ~3 hours
Status: First prototype built
With the advancements in AI, power and lower cost of sensors the need for a more approachable soft actuator is required. In a effort to bring robotics into the home and office we have been developing a new pneumatic hybrid linear actuator based partly on a subset field of robotics known as soft robotics. This actuator is a hybrid as it has a hard protective shell around the silicone muscle of the device.
The key goals were:
- Where possible use low cost materials
- Ensure it is easy to mount
- Be human compliant
- Have a considerable power to weight ratio
- Have it be a stack-able design (place more then one in a chain to multiply stroke distance)
The actuator that is shown has a calculated stroke of about 33.8mm, though this has yet to be tested. The parts for the body and molds have been ordered to experiment with the actuator to fine tune the design. Shown below is a soft robot arm we quickly designed to test the feasibility of the actuator in a use case. It was a fruitful endeavor, showing us critical design elements that were already corrected. This actuator is based on negative pressure produced from a diagram pump and controlled by a PWM modulated air valve. We are also looking to options for a internal feedback sensor to give a report on the status of the muscle, likely this will be in the form of a flexible strain gauge bonded to the side of the silicone structure. Multiple actuators and be placed parallel on the same electronic air valve or individually controlled. These type of compliant actuators will be needed for the future for intelligent adaptive AI, as they will be able to interact with humans and have the flexibility to make mistakes without causing damage to the system.
If you are looking to experiment with soft robotics I suggest checking out the Soft Robotics Tookit, a website created to show current research and build guides.