Single Axis Rotator
Analog Devices, Inc. Woburn Massachusetts
Product Engineering Intern
Summer 2016
Challenge:
Create a cost-effective method of measuring gyroscope sensitivity across an oven temperature sweep.
Solution:
Designed, built, and programmed a single-axis rotator able to precisely maneuver the gyroscopes within an oven while remaining adjustable, robust and user friendly.
Skills:
LabVIEW, JMP, SketchUp, soldering
For my Product Engineering Internship at Analog Devices, I was on a team working on MEMS gyroscopes for rollover detection in cars. Before the gyroscopes can be rolled out, the parts must be tested and verified in a variety of conditions. Temperature sweeps provide performance measurements across temperature extremes, but are confined to closed ovens. Measuring the sensitivity of gyroscopes during a temperature sweep is difficult because it requires large, expensive ovens that are also capable of rotating their contents. My main project was to design a new system for measuring the sensitivity of gyroscopes across a temperature sweep using the in-lab ovens.
the single axis rotator in action
concept sketch for two part system: external servo motor, internal support
final 3D model, 80-20 frame, G-10 shaft, custom aluminum mounting plate
front panel for LabVIEW code to control the servo with a function generator
partial block diagram for laptop/function generator/servo interface
One of the primary motivations for my project was to improve upon the reliability of current in-house testing of gyroscope sensitivity. Until my project, the only way to measure the gyroscopes was by rotating them by hand. I tried this technique and compared the results with my new single axis rotator, measuring the sensitivity of one gyroscope ten times using each method. The results were both more accurate (closer to the 80.0 actual value) and precise (more consistent) when compared with the by hand method. A quick t-test revealed that the two data collection methods were significantly different, and my boss was satisfied with the results. We continued to use the device to measure the sensitivity of critical parts during testing.
I had a number of key takeaways from working on this project. I learned to code efficiently in LabVIEW and to compartmentalize my code to allow easy implementation into the company's existing code. I interfaced with a variety of testing equipment including temperature ovens and function generators. I designed and built a custom aluminum rig with parts from McMaster-Carr. I learned new soldering techniques and debugging strategies. I became comfortable with ADI's workflow and learned an incredible amount about MEMS gyroscopes and accelerometers.
To conclude the summer, I wrote a datasheet detailing how to use my device in order to ease its transition into the workflow of ADI.