Controls and Actuation

The finished actuator can be controlled with any electro-pneumatic control system, such as the ones included in the Soft Robotics Toolkit.

In the following two subsections, two simple ways of controlling the actuator is described:

  1. Syringe Actuation
  2. Arduino Control

Both of these solutions are fairly simple and easy to assemble. The Arduino control system can be assembled without the need to solder anything. This makes both viable for introductory courses on soft robotics or workshops were participants have only limited or no experience working with electronics.

Bill of Materials


1. Syringe actuation

  • Syringe (60ml)
  • PVC tubing (ID/OD 1.5/3mm)

2. Arduino control

  • PVC tubing (ID/OD 1.5/3mm)
  • AA battery pack (that will hold four AA batteries)
  • 4x AA batteries
  • 2x Low-noise DC pump (Mitsumi R-14 A213 370 DC 6V)
  • 2x Solenoid valve (Fa0520D normally closed 6V)
  • 2x Y connector pieces for tubing 
  • Motor shield for Arduino
  • Arduino Uno microcontroller
  • Computer for programming the Arduino
  • USB cable to connect the Arduino to the computer


  • Bamboo skewer
  • Cigarette lighter

Syringe Actuation and Arduino Control

1. Syringe Actuation

 The easiest way to test the actuator is by using a syringe (60ml or more) for actuation by hand.

Materials for syringe actuation  

  • The inner diameter of the tubing needs to be expanded a bit to fit onto the syringe nozzle.
  • Use a lighter and a bamboo skewer to do this by carefully heating up the end of the tubing while pushing in the skewer to expand the diameter of the tubin g.
    Expanding the PVC tubing by heating it
    Expanding the PVC tubing by heating it
  • Once the end of the tubing is connected to the syringe, a tight seal can be attained by carefully heating it once again with a cigarette lighter and allowing it to cool off, as this causes the PVC to contract around the syringe nozzle.

The actuator can now be tested:



2. Control with Arduino

One or two actuators can also be controlled with a simple setup consisting of an Arduino microcontroller equipped with a motorshield and pneumatic solenoid valves, air pumps, and a battery pack. The components are assembled as shown in the photo. All wires are connected by using the screw connectors on the motor shield. It is a good idea to expand and contract the tubing, as described above, when fitting it onto the Y connectors, pumps, and valves.

Arduino control setup
Arduino control setup

With the Arduino setup, the inflation and deflation of the actuators happens by switching the pumps and valves on and off. With the addition of the motor shield the Arduino microcontroller can take care of this. Sample control code that can be uploaded to the Arduino from the Arduino IDE is provided in the downloads section. Sensors can also be integrated into the setup as shown in the video below, where a light-dependent resistor triggers the actuation.