Tension Pistons: Amplifying Piston Force Using Fluid‐Induced Tension in Flexible Materials

Abstract

Pistons are ubiquitous devices used for fluid-mechanical energy conversion. However, despite this ubiquity and centuries of development, the forces and motions produced by conventional rigid pistons are limited by their design. The use of flexible materials and structures opens a door to the design of a piston with unconventional features. In this study, an architecture for pistons that utilizes a combination of flexible membrane materials and compressible rigid structures is proposed. In contrast to conventional pistons, the fluidpressure-induced tension forces in the flexible membrane play a primary role in the system, rather than compressive forces on the internal surfaces of the piston. The compressive skeletal structures offer the opportunity for the production of tunable forces and motions in the "tension piston" system. The experimental results indicate that the tension piston concept is able to produce substantially greater force (more than three times), higher power, and higher energy efficiency (more than 40% improvement at low pressures) compared to a conventional piston, and these features enable myriad potential applications for the tension piston as a drop-in replacement for existing pistons.

Impact of 3D Printing Technique and TPE Material on the Endurance of Pneumatic Linear Peristaltic Actuators

“…These reasons have been pushing the scientific community to explore new ways to implement pneumatic actuators. Several approaches have been followed, namely, by (i) using flexible materials [ 4 , 5 , 6 , 7 , 8 , 9 , 10 ] to embody the actuator, (ii) using hybrid electric-pneumatic actuators that combine the simpleness of control of electrical actuators with the pneumatic actuators low stiffness [ 11 , 12 ], and (iii) developing a new piston configuration to increase the energetic efficiency of conventional cylinders [ 13 ].…”

Model and Experimental Characteristics of a Pneumatic Linear Peristaltic Actuator

“…A novel idea that has recently been presented in [8] is the use of a deformable piston structure covered by a flexible membrane: the so-called tension piston. Significant energy improvements are claimed in [8], as the configuration allows pneumatic energy to be converted into mechanical energy using two different ways: pressure on the piston rigid areas and a pneumatic-induced tension on the piston flexible membrane. This configuration presents some potential advantages over conventional techniques.…”

“…Since a flexible membrane is used for sealing, it has no leakages and exhibits low friction forces, making it potentially more appealing for servo control. In addition, in [8], it is shown that the tension piston can develop higher forces when compared to a conventional piston at the same pressure. Although the authors of [8] sustain that this leads to substantially higher power and energy efficiency, the conventional actuator used for comparison in [8] uses conventional seals.…”

“…In addition, in [8], it is shown that the tension piston can develop higher forces when compared to a conventional piston at the same pressure. Although the authors of [8] sustain that this leads to substantially higher power and energy efficiency, the conventional actuator used for comparison in [8] uses conventional seals. This means that the datum cylinder presents high friction forces that apparently were not accounted for in some of the comparisons made in [8].…”

“…Although the authors of [8] sustain that this leads to substantially higher power and energy efficiency, the conventional actuator used for comparison in [8] uses conventional seals. This means that the datum cylinder presents high friction forces that apparently were not accounted for in some of the comparisons made in [8]. Some drawbacks are as follows: (i) the configuration potentially leads to lower endurance, as it involves a flexible membrane, (ii) it presents a nonlinear force dependence with the piston position, and (iii) it requires a higher actuator length for the same stroke when compared to conventional actuators.…”