Pneumatic Logic Systems for Selectively Operating Distributed Pneumatic Elements

Abstract

Microfluidic and pneumatic logic systems are valuable for applications such as lab-on-a-chip devices, soft robotics, and factory automation. These systems are particularly advantageous when metal or electronic components are impractical or when there are constraints on the control system volume or weight. This paper introduces a novel individual membrane valve that functions as a set-reset latch and can reduce the number of valves required for some pneumatic or microfluidic logic systems. An application of pneumatic logic systems in soft robotics is the access to multiple tethered pneumatic elements through a reduced number of pneumatic lines. To this end, this paper proposes two pneumatic logic systems capable of selecting among multiple distributed sets of pneumatic elements and operating the elements of the set simultaneously and independently through the different pneumatic lines. The selection is achieved via a sequence of pressure pulses applied on the same lines used afterwards for operation. Two prototypes of these pneumatic logic systems were built and successfully demonstrated, consisting primarily of set-reset membrane valves and powered by binary high/low pressure sources. The first prototype features a hierarchical network with four lines and five sets of three pneumatic elements each; the second prototype features a non-hierarchical network with five lines and twelve sets of four pneumatic elements each.