The figure shows an air cylinder that could be used as an actuator in a control system. The inlet ports at the top and bottom can be exposed to a supply at pressure Ps and temperature Ts or to exhaust at Pa and Ta. This switching would be accomplished through some valving, which is not shown. Construct a bond graph model of this component that is ready for installation into a system. Assign causality so we know what causality is acceptable from any attached system.
