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.

Modeling Leakage Flow from External Gear Pumps

One issue with using external gear pumps in fluid power is the leakage produced from the pumps. This issue is further compounded because based on the tolerances a company uses to manufacture the pump, estimating the leakage accurately can become a difficult task to achieve since the amount of leakage depends on these tolerances. My research mainly focuses on writing MATLAB code and running simulations to estimate the leakage as a function of the tolerances provided to us. In the future, we would like to experiment with pumps to see if our simulation data holds up in real world experiments.

Validation of Hydraulic Cylinder Cushion Design Model

The design process used to determine hydraulic cushion geometry involves trial and error with physical components and thus requires substantial costs and time.  We have a computer model built to enable virtual prototyping. To validate this model, we have built a physical test stand with a cylinder equipped with a tapered cushion. We will gather data from the test stand to better the model. My contribution was to make this test stand a reality by incorporating sensors, designing and building hydraulic circuits, and coding Danfoss microcontrollers for solenoid valves and cRIO for data acquisition. The model has potential to better the current design process and will save valuable time and money. 

Title and Elevator Pitch Draft

Testing Platform for a Partial Stroke Piston Pressurization Pump/Motor

In previous research efforts, a design was realized for a partial stroke piston pressurization hydraulic pump/motor which can achieve high efficiency by altering displacement by varying the pressurization duty cycle. I contributed to the project by constructing a testing platform to demonstrate the efficiency of a prototype through its full range of operating settings. This testing platform is noteworthy because it uses recirculation to reduce the load on the external pressure supply and it incorporates an array of pressure, temperature, flow, torque, and speed sensors to capture a detailed profile of the pump/motor's performance.

Poster Title and Elevator Speech

Comprehensive Model of a Hydraulic Free Piston Engine

The free piston engine (FPE) is a type of engine with no crankshaft, allowing for less restricted, piston motion.  Since this technology is still in its developmental phase, my contribution to the research has been to produce a comprehensive model of engine operation in Simulink.  The FPE has the potential to greatly increase fuel efficiency of on- and off-road vehicles because, with fewer moving parts, there is much less friction present than in the widely used internal combustion engine.

Week 4 Update

Hello fellow-researchers!

I am going to share what I have been doing so far in my project. One of the major goal of my project this summer is to develop an ASTM new filterability test method for hydraulic fluids using mass flow method and correlating the volumetric and mass flow method results. This week I could connect the Mettler Toledo Balance-link software into the filtration apparatus so that I can collect dynamic weight of the filtered sample in every second interval. I tested the samples that I received from Chevron. It was very interesting to see how ashless biodegradable hydraulic fluids creates static electricity during the filtration process. This static electricity generation damages the filter media and disrupts the filtration process. I have discussed this with my advisor Paul, and he recommended me to use Electrostatic Dissipative (ESD) media during the 

filtration process and compare the results with previous ones so we can come up with a solution. This will be my future plan as of now. 

I hope everyone is having a great summer !

Tahseen 

Week 3: Research environment at MSOE

Hello Everyone,

I just wanted to share the research environment at MSOE so far. Throughout the summer, I have been working in MSOE’s Fluid Power Institute^TM in Paul Michael’s research team. The environment of the lab is very nice, as I can interact with other graduate and undergraduate students working in the lab. In the beginning, I was a little scared by seeing the fast pace environment in the lab. But eventually I am getting used to the pace as I am getting deeper into my project. My advisor Paul and graduate students Mercy and Pawan were very helpful explaining everything very efficiently. Plus, I like how my advisor gives me freedom to come up with different solution when I ran into any obstacle in my project. I like how he pushes me to think critically and do more research on a topic. It makes me more efficient and inspires me to work even harder. As the summer goes on I expect to get a deeper sense into the tribology and filtration of different hydraulic fluids.

I hope everyone is having a great time in their projects as well.

Tahseen

Week 6

Hi everyone,

I was able to contact Tom Barraclough this weekend and after conversing he sent me an attachment of an excel spreadsheet with equations in them for calculating the amount of ferrous particles in ppm for a sample. The equations used in the excel spreadsheet are hypothetical, meaning that if the sample tested is known to have only ferrous particles in it, then the equations will give the ferrous particle concentration in the sample tested. How the equations work is that you copy and paste the particle imaging count results into the excel spreadsheet and the equations saved in the excel spreadsheet will calculate the ferrous particle concentration in ppm. Knowing this, I realized that I could input the particle counts for the S-1000 test dust reference samples because they are known to only contain ferrous particles. I put the results in the excel spreadsheet and graphed the results. The Vertical axis represents the ferrous particle concentration in ppm and the horizontal axis is the reference samples containing S-1000 iron test dust. The blue bar is the actual iron ppm that we calculated using our calibration sheet. The orange bar is the calculated iron results from the excel sheet provided by Tom for the reference samples. The black bar is the results of ferrous concentration in ppm that the Q230 counted for the reference samples. The actual and calculated iron ppm are relatively close to each other, but the results that the Q230 yields are not close to the actual and calculated.

Week 5

Hi everyone,

Happy fourth of July! I started to look at the results I had received from the field samples and showed them to Paul. He pointed out that for most of the results, there was no ferrous particle count in ppm. This is an issue because it means that the magnetometer is not counting the concentration of ferrous particles correctly because we compared one of the field samples to a ferrogram result of that sample. The ferrogram shows that there are at least a couple hundred of ferrous particles in ppm for that sample, yet the Q230 was not able to detect them. I had emailed Tom Barraclough one of the inentors of the Q230 to ask him why this phenomenon might occur. Unfortunately I will not be able to contact him until next week because he is unavailable this week. The graph are the results of the field samples that I tested last week. The left vertical axis represents the ferrous particle counts of particles >25 microns. The right vertical axis represents the total ferrous particle concentration in ppm and the horizontal axis is the field sample tests. The green bar is the counts for each of the field sample particle counts of particles >25 microns and the orange bar is the ferrous particle concentration. As shown by the graph there are only five orange bars for a total of 38 tests and the ferrogram from sample 16122 (last two tests located on bottom right)had at least a couple of thousand ferrous particles in ppm. I also made another batch of reference samples containing S-1000 iron test dust using the same S-1000 concentrate as the previous reference samples and tested them on the Q230.

Week 4

Hi everyone,

This week I prepared field samples which will be used to evaluate the dual magnetometer technology integrated in the Q230. What makes field samples so great is that they are hydraulic fluids from machines that have wear contaminants in them. Ferrograms have already been taken from the field samples that I will be testing and will be used to see if the magnetometer technology is able to detect ferrous particles properly. What makes the magnetometer technology unique to other ferrograph tests is that it can give ferrous particle counts and concentration in a faster amount of time. The procedure I used to prepare the field samples is presented below (this procedure was also used for the S-1000 reference samples and test dust concentrate samples). :

1. Agitate the sample in paint shaker for 10 to 20 minutes.
2. Weigh desired amount of original sample into 250mL test bottle.
3. Fill test bottle with MIL-PRF-5606 aerospace hydraulic fluid.
4. Shake test bottle in shaker for 5 minutes.
5. Sonicate for 30-45 seconds.
6. Degas until air bubbles exit fluid.
7. Run test samples through Q230 multiple times.

Unfortunately I was unable to finish the total 38 field samples that are to be tested because I ran out of the 5606 hydraulic fluid which is the solvent I use to prepare my test samples because 5606 is a very clean hydraulic fluid. 

Week 3

Hi everyone,

This week I conducted my first presentation for my project. Overall I believe I did decent, but I found myself confused on what to say and if what I was saying was properly spoken with the right terminology. The feedback I received from the advisors and the other REU students was very helpful and will be used in my next practice presentation. This week I also prepared another set of reference samples. The first sample was filled with 33.29mg of S-1000 iron test dust and 200mL of MIL-PRF-5606 hydraulic oil (sample will be called S-1000 concentrate). Next, different amounts of S-1000 concentrate was weighed into another set 250mL bottles filled with 200mL of 5606 fluid (will be called reference samples). These reference samples were then tested using the Q230 and the results were exported to excel. I forgot to mention last week that the amount of concentrate in the reference bottles were converted from grams to mg/L in excel to give us the amount of test dust in each reference sample. Then the mg/L concentration was graphed with the amount of particles >4 microns, where the X-axis was test dust concentration in mg/L and the Y-axis was particles >4 microns in particles/mL. Then a trend line was created from the given points to give the amount of correlation between all of the points on the graph. This same process was done with the reference samples filled with S-1000 concentrate. This graph has on X-axis the S-1000 test dust concentration in mg/L, and the Y-axis having the total ferrous particle concentration in ppm (mg/L). The reference samples filled with test dust concentrate have a 99.81% correlation while the reference samples with S-1000 test dust concentration have an 80.72% concentration.  

Week 2

Hi everyone,

The new technology that I will be using for analyzing large ferrous particles in hydraulic fluids arrived last week and the new technology is the Lasernet Fines Q230. The Q230 consists of a particle imaging system which counts particles >4µm (microns) in a fluid and a dual magnetometer system that counts ferrous articles >25 microns and the total concentration of ferrous particles in parts-per-million (ppm). I will be focused on the dual magnetometer system of the Q230 because this is the new technology that can give a quantitative result of ferrous particles in a given hydraulic fluid. Before testing we had to make sure the Q230 was functioning properly by calibrating it with the given calibration fluids provided. The Q230 is functioning properly when the given calibration fluids are tested on it and yield a certain result. After configuring the Q230 to the computer we stared to calibrate it and after a couple of hours the Q230 yielded the proper results of the calibration fluids and worked properly. I also read the Q230 instruction manual before I started conducting tests on it and gave a status report. This week I also prepared reference samples by creating a concentrated 250mL bottle filled with 18.56mg of ISO medium test dust and 200mL of MIL-PRF-5606 hydraulic oil (sample will be called test dust concentrate). Next I filled separate 250mL bottles (reference samples) with different amounts of test dust concentrate and tested them on the Q230.

Week 1

Hi everyone,

This weekend I arrived at Milwaukee School of Engineering (MSOE) which is located in Wisconsin. Upon my arrival I was greeted by my advisor Paul Michael who drove me to the Grohman Tower which is one of MSOE’s dorms. Paul told me that my project is going to be analyzing large ferrous particles in hydraulic fluids and I will be using the Lasernet Fines Q230 to do this. During the week I was introduced to the rest of the REU students at MSOE, two of which will be going to the University of Johannesburg which is located in Africa. The week here at MSOE consisted of meeting with my advisor and the rest of the other advisors working on various research projects. It was also orientation week where the rest of the REU students and I were accompanied by Betty Albrecht and Subha Kumpaty. I also learned a little of solidworks because there was a solidworks training taught by the REU student Andrew Gray. There was also tours around the campus and discovering fun events here at Milwaukee hosted by Rick Gagliano.