John A. McCartney
Efficient, Inspired Design
Sensor Design
All three of my sensor design projects started with laboratory setups that could monitor some stimulus (rotation, temperature, strain). Using the output from the laboratory setups integrated with an nScope circuit board, a MATLAB program was used to calibrate the sensors. The sensors werte then programmed to complete a specific function.
Strain Gauge Scale
A strain gauge sensor was calibrated using several test masses. The change in recorded resistance of the strain gauge was fit to a curve in MATLAB. Once calibrated the cantilver beam setup pictured left could be used as a scale.
Motor Characterization
The angular velocity of a DC motor was measured using a Hall effect sensor in the apparatus to the left. Once calibrated, a program was developed within MATLAB to control the motor output.
Thermostat
This sensor combined the use of thermistor, a heat sink, and a motor driver to program the apparatus to drive itself to a set temperature. Using high and low limits and a time function, my partner and I were able to design a thermostat that functions similar to that of the ones used in our homes.