Stoneridge Inc. Canton, MA
For my first co-op I worked as a member of the advanced development team at Stoneridge, Inc. Working at Stoneridge was a great experience for so many reasons. I gained a lot of hands-on experience in the machine shop, laboratory, and learned how to create 3D models using Professional Engineer for prototyping and testing purposes.
Thermocouple Prototyping
The majority of my time at Stoneridge was spent building thermocouple samples. Building a thermocouple like the ones that we were prototyping, required many intricate processes from high accuracy laser welding to the tenth of a millimeter, to precision crimping, to fine cuts on the lathe, to temperature testing and x-ray inspection.
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Laser welding recorded in slow motion.
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X-ray inspection of a completed thermocouple which revealed a short circuit in the PCB between the 4th and 5th terminals.
Testing of Thermocouple Weld Integrity
In order to show potential customers that our thermocouple welds were durable, we needed to run a vibration test according to a Mercedes spec. I was given the responsibility of designing the necessary fixturing for this test. The fixture needed to securely hold the ends of 10 thermocouples, while allowing the other ends to be oscillated back and forth in order to put cyclic stress on the thermocouple weld joints.
Time lapse of vibration fixture assembly.
Magnet Characterization Study
At Stoneridge, I independently conducted a two-month magnet characterization study for the turbo actuator project of the advanced development team. The purpose of the study was to investigate the effects of high temperature cycling on the strength of the magnetic fields of the magnets.
The first step of the study was to design a fixture in order to hold the magnets for testing. The magnets needed to be held in a way that ensured that the Gauss probe (red) and the magnet (yellow) were kept at a constant distance from each other (2mm gap). Because magnetic fields vary by distance squared, it was very important to make sure that the measuring distance remained a constant 2 mm to ensure no incorrect data was collected.
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After designing the fixturing in Professional Engineer to hold the magnet and Gauss Probe, my design was brought to reality by the model shop at Stoneridge.
During my time at Stoneridge, I had many models made at the model shop. Working with the model shop helped me learn a lot about design, dimensioning, geometric tolerances, and how to design things in a way so that they can be easily machined. |
Six magnets were used for testing, resulting in over 3,500 Gauss field strength readings taken using my fixturing. After completing all of the readings and analyzing the data, I determined that the magnetic strength of these magnets was severely reduced by high temperature cycling. The engineers were actually surprised by how much the strength of the magnets was reduced by the temperature cycling and realized that they knew less about the characteristics of the magnets than they had originally thought.