System for detecting operation of a fluid pressure actuator

A system for detecting operation of a fluid pressure actuator, the fluid pressure actuator being provided with a double-acting cylinder having a piston and an interior divided by the piston into a first pressure acting chamber and a second pressure acting chamber, the fluid pressure actuator being configured to switch a moving direction of the piston by switching between supply of operation air to the first pressure acting chamber and supply of operation air to the second pressure acting chamber, wherein the system is configured to detect a start time at which the piston starts to move and a stop time at which the piston stops moving,

• wherein the system comprises:
• a first pressure detecting unit configured to detect a first pressure value representing a pressure value in the first pressure acting chamber;
• a second pressure detecting unit configured to detect a second pressure value representing a pressure value in the second pressure acting chamber;
• and
• a detecting unit including a detection program configured to calculate an addition value of the first pressure value and the second pressure value, calculate a time differential value of the addition value, and detect the start time and the stop time based on a variation in the time differential value over time.