Design and Fabrication of Soft Pneumatic Muscles

Commercially available pneumatic muscles are bulky and have limited movements of contraction and extension. During summer my goal was to create silicone cast pneumatic muscles by designing a mold and using 3-D printers to then create these molds that could overcome these movement limitations. These are important because they can be used to create more wearable exoskeletons.  

Interface between a power regenerative test platform and data acquisition system

At the University of Minnesota, a power regenerative test platform has been built which is used to understand the performance of a hydrostatic transmission in a wind turbine. To understand the performance, the test platform contains 27 sensors. These sensors are used to monitor the test platform with real-time measurements. The big problem is that the sensors give off a current signal and the data acquisition system reads voltage signals. The two cannot understand each other if there isn’t a translation. Therefore, a solution is designing a circuit that is cleaner and more organized that the current circuit. The circuit will serves as the converter of current signals into voltage signals. This way the data acquisition system can read what the sensors are sending and we, as experimenters, are given real-time measurements.

Analysis of Ferrous Particles in Hydraulic Fluids

Hydraulic fluid power systems generate ferrous wear particles and improper analysis of particulate contamination may lead to catastrophic failure. Traditional ferrography methods analyze ferrous wear particles, but the results are qualitative and require an expert. This study validates the effectiveness of a new ferrography method that uses an automated dual magnetometer system which counts ferrous particles >25 microns and calculates iron concentration.  

“Emulating a Plastic Ankle-Foot Orthosis with a Hydraulic powered Ankle-Foot Orthosis”

Patients who are victims of cerebral palsy, live most of their life using Plastic Ankle-Foot Orthosis (PAFO) to support their ankles since they have weakened muscle coordination. Currently, it takes a patient multiple visits to a physician to get a PAFO with a correct stiffness prescribed. Therefore, a Hydraulic powered AFO was invented that can emulate the stiffness of a PAFO. The stiffness on the HAFO can be easily altered in comparison to a PAFO, which allows the physician to test a range of stiffness's on a patient all under one visit. I was involved in the data analysis portion of the project, which from here we realized what changes within the Controls System script for the HAFO needed to be made to successfully emulate a PAFO. Our end results showed that a PAFO stiffness was successfully emulated, the next steps to this project would be to use the HAFO for coming up with the best possible design for a PAFO with a specific application. 

Elevator Speech: Pneumatic Actuated Upper Body Exo-skeleton

Millions of industry and manufacturing workers every year suffer from Neck Muskuloskeletal disorders which cause neck pain and cost a lot of money to individuals and companies. The most common reason that leads to injuries is awkward static postures that involve the upper extremes being raised for a long period of time. My project's goal is to limit these injuries by designing an active exoskeleton which is going to support the upper extremes by canceling out their weight. The design is such that the arms will be able to move completely free and it is going to involve pneumatic actuation.

Liquid-Gas Interface Stability in Inverted Liquid Piston Air Compressor

This experimental research focuses on the stability of the liquid-gas interface in an inverted liquid piston air compressor. Here, a column of water rests on a stationary piston, and porous media is added to increase heat transfer and thus efficiency. It was found that wider spacing, longer lengths, and smaller diameters of porous media result in greater stability. The results will help determine potential applications and operating conditions for this technology.

An Investigation of a Mass Flow Rate Method for Evaluating the Filterability of Hydraulic Fluids

The ability of the fluid to retain its filterability properties is critical for efficient, reliable machine performance. This is particularly true for biodegradable fluids used in environmentally sensitive areas. In this research, hydraulic fluids and lubricants of various base oil and additive composition were evaluated using a modified version of ISO 13357 that utilizes mass flow rate measurements to assess fluid filterability. A comparison of volumetric and mass flow rate filtration ratios reveals that the use of mass flow rate to determine filterability yields comparable results while improving test repeatability. These findings are the basis of a new ASTM standard to be proposed for the measurement of fluid filterability and compatibility.