A Mechatronic System for the Magnetic Manipulation of Biomedical Specimens
As part of a research project to develop a magnet-based treatment delivery system, I created a manipulation framework from 3D-printed pieces, Arduino microcontrollers, stepper motors, and magnets to move magnetic specimens in a controlled environment.
Final setup of the manipulation system, including all 3D-printed pieces, wiring setups, and specimen.
The video below is the final product in action. The cells coupled to magnetic nanoparticles in the central chip can be manipulated around obstacles by the user-controlled movement of four different magnets.
Problem Statement for System Development:
To determine the efficacy of the nanoparticle technology, cell masses need to be manipulated and visualized. Hand-held magnets and light microscopes are no longer sufficient for this purpose and are causing more problems than they solve for the visualization.
Early Design:
My first steps in designing this system were to identify design specifications. Based on the previous method of specimen manipulation and visualization, there were only two: increase the axes of manipulation from one to two and reduce user interaction with the specimen, specifically hand-held magnet control.
After identifying these specifications, I created a general sketch (above right) of magnet motion and pieces that I wanted to include in the system. This was especially important for the coding phase of the project for motor motion. I followed that general sketch with a wiring schematic (above, left) for all of the motors, motor drivers, joysticks, and microcontrollers I would be using in the system to make the actual construction easier.
3D Design:
Almost all of the non-electronic components in this system were 3D designed and printed. These pieces include the rack-and-pinion system (below), the rack-and-motor casing (below), and the holder for the specimen container (below), as well as C-clamps, a joystick setting, and several different centerpieces.
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Preliminary Testing:
I completed a preliminary testing phase to work our bugs in the system and the code using paper clip fragments (below) in the same kind of container that contained the cell masses. Through this testing, once all of the bugs were worked out, I was able to determine that the system would be effective on the cell masses.
Here, the system is being tested for efficacy using paper clip fragments and only part of the systems full functionality.
Through this project, I gained hands-on design capabilities, knowledge of the Arduino open source coding language, electronics experience, and familiarity with CAD softwares. I also learned project planning and management strategies throughout the design process.