The pneumatic vibration isolator is economical, has no risk of contamination, and attains high vibration isolation performance by lowering the natural frequency. Pressure feedback control is used to improve the response speed of the pneumatic vibration isolator and keep the internal pressure of the pneumatic actuator constant. In this paper, the vibration isolator was actively controlled by estimating the internal pressure of the pneumatic actuator with the displacement signal. A pneumatic actuator was modeled and its dynamic characteristics were identified through frequency response measurements. A pressure observer based on relative displacement was designed, and the observer control gain was adjusted with nominal model and experiments. Pressure estimation performance and active vibration suppression performance using a pressure observer were verified through experiments. The pressure of the pneumatic actuator was estimated by the observer, and measurement noise was eliminated effectively. In addition, vibration isolation performances of direct and estimated pressure feedback showed no difference, verifying the effectiveness of the pressure observer.

A pneumatic tube system is a system that transmits and receives objects quickly inside pipes and is used in urgent situations or when transferring or returning objects. It is mainly used in hospitals, large marts, and automation systems. For long-distance transportation (up to 10 km) high pressure is used at industrial plant industrial sites. A large amount of flow rate and high pressure are used to generate instantaneous pressure and flow to the opposite side, where the transport target is stored in a separately manufactured carrier and transported. Specially manufactured carriers considering significant frictional force in the straight, curved, rising, and lower sections during long-distance transport are employed. The other party experimentally generates reverse pressure to lower the care speed inside the transfer pipe that arrives at a high speed and operates the worker valve to reduce the speed, but the valve must be operated every time according to pressure and distance changes. In the present work, a method of arriving at a carrier in a stable pipe through speed reduction by controlling the flow rate and reverse pressure depending on the distance from the transmission unit and calculating the reverse pressure compared to the teleportation speed is presented.