Pneumatic actuators

This is a continuation of my previous post about actuators.

Pneumatic actuators have the following benefits over electromechanical actuators: They can be made to require less space, and it is often easier to direct their force where it's actually needed. This is especially so with the Air muscles, which are soft and bendable. They also have natural cushioning that may be desirable when building a robot that needs to be gentle with its surroundings (or in my case, impact and shock resistant).

Pneumatic cylinder

Air muscle

Air compressor

Solenoid valves on manifoil

On the negative side however, controlling the force of pneumatic actuators will be much harder, since you rely on the flow of gases in tubes which will inevitably add some delay to the whole control loop. Also having top precision is also very hard, especially for air muscles due to their very soft nature. And finally, they come with some baggage. You will need an air compressor on board your robot, or a solid supply of gas under pressure, and each actuator will need 1 or 2 dedicated solenoid valves for controlling air flow. With many actuators (36 in my worst case scenario) this ads up to a huge manifoil with a carnage of tubes perturbing in every direction.

So pneumatic actuators in my project? Possibly...

My next post will cover hydraulic actuators.

--Lennart