Cincinnati Children's Hospital Medical Center
Sports Medicine Department
A Research Experience
After not being placed in the SURF Summer program, I was determined to find myself a summer research opportunity. I wanted any type of research experience I could find in order to see firsthand if it is actually something I could see myself doing in my future career path. Moreover, I wanted to start making connections with doctors and researchers in my areas of interest, as these will be very important in the upcoming years.
As the result of various emails and a few personal meetings, I was offered an internship position in the Sports Medicine Department, working with Nate Bates, a graduate student in Dr. Tim Hewett's lab. The project I was to be assigned initially did not seem very exciting, however that could not have been a more inaccurate judgement. My task was to debug the problems encountered in a musculoskeletal modeling and simulation software being used to analyze subject motion. In order to attempt this, I had to teach myself how to use the program, OpenSim, as well as XML coding language.
OpenSim works in multiple steps to model subject motion, captured from the Human Performance Laboratory using 3-D Motion Capture systems. These steps include model scaling, Inverse Kinematics, Inverse Dynamics, Residual Reduction Algorithm, and Computed Muscle Control. When I began, the results from RRA were unacceptable, producing residual error values in the thousands, when values less than 100 are desirable. Because of these large results, CMC would not even run successfully. In order to achieve the desirable RRA results, I made several changes to the input variables necessary for RRA, which included Actuator and Task files as well as minor selective options such as data filtering frequencies and time delays. Upon achieving manageable RRA errors, my focus turned to CMC, which uses data from all the previous steps as well as ground reaction forces to compute muscle excitations that drive the model through the motion. Progress for CMC was achieved in a similar manner to RRA, making minor changes to the various inputs based on each trial's results.
Looking back, I am extremely grateful for Nate believing that I could make progress on this project rather than simply turning me away (as he has had several poor experiences with interns in the past). Not only have I learned how to use an extremely unique and valuable program that is relatively unknown, but I also learned an incredible amount about biodynamics of the knee. This was very fitting, as quite often the material I was being presented in my Biomechanics class directly corresponded to my project. It was very satisfying to finally start to see application of classroom material in the practical field.
The document below is the published paper from the creators of OpenSim, describing in great detail the program, its features, and its applications.
As the result of various emails and a few personal meetings, I was offered an internship position in the Sports Medicine Department, working with Nate Bates, a graduate student in Dr. Tim Hewett's lab. The project I was to be assigned initially did not seem very exciting, however that could not have been a more inaccurate judgement. My task was to debug the problems encountered in a musculoskeletal modeling and simulation software being used to analyze subject motion. In order to attempt this, I had to teach myself how to use the program, OpenSim, as well as XML coding language.
OpenSim works in multiple steps to model subject motion, captured from the Human Performance Laboratory using 3-D Motion Capture systems. These steps include model scaling, Inverse Kinematics, Inverse Dynamics, Residual Reduction Algorithm, and Computed Muscle Control. When I began, the results from RRA were unacceptable, producing residual error values in the thousands, when values less than 100 are desirable. Because of these large results, CMC would not even run successfully. In order to achieve the desirable RRA results, I made several changes to the input variables necessary for RRA, which included Actuator and Task files as well as minor selective options such as data filtering frequencies and time delays. Upon achieving manageable RRA errors, my focus turned to CMC, which uses data from all the previous steps as well as ground reaction forces to compute muscle excitations that drive the model through the motion. Progress for CMC was achieved in a similar manner to RRA, making minor changes to the various inputs based on each trial's results.
Looking back, I am extremely grateful for Nate believing that I could make progress on this project rather than simply turning me away (as he has had several poor experiences with interns in the past). Not only have I learned how to use an extremely unique and valuable program that is relatively unknown, but I also learned an incredible amount about biodynamics of the knee. This was very fitting, as quite often the material I was being presented in my Biomechanics class directly corresponded to my project. It was very satisfying to finally start to see application of classroom material in the practical field.
The document below is the published paper from the creators of OpenSim, describing in great detail the program, its features, and its applications.
Reflection Essay | |
File Size: | 19 kb |
File Type: | docx |
OpenSim In-Depth Description | |
File Size: | 4214 kb |
File Type: |