The video below is an excerpt from Erin Kennedy's February 2015 Robot Party. The Robot Party is an online community of robot makers who share their projects and discuss robotics ideas. In the video I demonstrate the control board, and also discuss how this project can be a jumping off point for people interested in using the soft robotics toolkit.
The control board performed very well. As mentioned in the design section, there are certain differences between the prototype and the fluidic control board design defined on the main Soft Robotics Toolkit.
- Pressure sensors were eliminated to reduce cost.
- An 8-valve manifold was used to leave room for future expansion.
- Instead of an on-board compressor, an off-board workshop air compressor supplies the necessary pressurized air.
- Power is provided by one 12V DC and one 24V DC supply.
- A sensor shield (daughter board) was used with the microcontroller to make electrical connections easier.
- Five potentiometers (one for each finger) provide manual control over each actuator.
- One potentiometer allows you to vary the Pulse Width Modulation (PWM) frequency used to control the flow of air to the actuators.
- A toggle switch allows you to either select manual control with the five potentiometers, or programmed control.
- A 12-position rotary switch lets you select between twelve different hand positions and gestures.
- Choice of black for the color is much cooler.
User Interface
The controls knobs and switches are all located on the outer edges of the board so they are easy to reach. As I built the prototype for myself, nothing is labeled. I did find that when I invited others to use it, the controls were fairly intuitive. Even children quickly learned how to operate the hand.
Expandability
The use of an 8-port manifold allows for controlling more pneumatic actuators. Actuators could be added to move control a robotic arm or to add additional degrees of freedom to the existing hand.
Because the current control panel is fully populated, it may have to be replaced or modified if additional actuator control is desired.
The programmable nature of the Arduino Mega microcontroller allows for plenty of software expandability.