Soft fluidic robots are typically controlled using manifolds containing large and rigid electromechanical valves. These bulky controllers limit scalability and hinder motion, in particular for untethered soft robots. There has been recent interest in using fluidic controllers analogous to electrical logic gates and microcontrollers to replace rigid valve systems. However, these microfluidic networks typically operate with small volumes, low flow rates, and low pressures relative to what is needed to power fluidic soft actuators. This article presents the design, fabrication, and analysis of a soft, fluidic amplifier as the “missing link” between microfluidic analogies of microcontrollers and the high fluidic power loads representative of soft actuators. The article demonstrates amplification gains of pressure signals up to a factor of four. The amplifier is a step toward fully autonomous soft robots by allowing designers to develop control strategies from soft materials with minimal additional rigid components or tethering.
Anterior cruciate ligaments (ACL) injuries account for a significant proportion of all sports-related injuries. Despite successful completion of a rehabilitation program, about 35% of ACL patients experience re-injury after return to sport, and studies have identified persistent quadriceps strength deficits as a potential cause [1–3]. Deficits in quadriceps strength can be monitored throughout rehabilitation using muscle strength testing. The most common test protocol involves isometric testing of quadriceps strength whereby the knee is extended against a static resistance. In this method, the clinician uses their strength to resist the patient’s motion and subsequently assigns a qualitative value of strength. The highly subjective nature of this test has motivated clinicians to use devices that can more accurately assess quadriceps strength.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.