Hardware Portfolio
As a kid, I used to love ripping out motors, LEDs, and parts from broken electronics, and then putting them together in my own little inventions. Here are some of the things I've done on the hardware side:
- Electronics Construction, Use, and Troubleshooting
- APOLLO Power and Signal Cables
- Etch-a-Sketch Magnetometer
Electronics Construction, Use, and Troubleshooting
I spent a lot of time as a graduate student assembling and troubleshooting our hardware. And I only shocked myself once in 4 years with a puny 30 Volts. Here are some of the tools I used and feel quite comfortable with:
- Oscilloscopes
- Function Generators
- Power Supplies
- Stepper Motors and Motor Control Boards
- Multimeters
- Soldering Irons
- CAMAC modules
- Serial controlled stepper motors, cameras
- PC video capture cards and cameras
APOLLO Power and Signal Cables
One of my responsibilities in the APOLLO lunar laser-ranging research group at UCSD was to order and build many of the data and signal cables our apparatus needed. Our detectors and laser were mounted onto the telescope. The power supplies and computers, however, were in a small cabinet next to the telescope. Thus, there cables were needed to connect the two. I used shielded twisted pair cable for many of the power lines, and coaxial or ribbon cable for many of the data lines. We used coaxial, D-style, and molex connectors on many of the cable ends. In summary, I cut, soldered, and crimped a LOT of cables.
Etch-a-Sketch Magnetometer -- LabVIEW
In one of my undergraduate physics labs, a friend and I had the clever idea to stick a Hall Effect probe (which outputs a voltage proportional to an applied magnetic field) onto an Etch-A-Sketch stylus. We connected the gears of the Etch-A-Sketch to stepper motors, and wrote a virtual instrument in LabVIEW to control the motors, read out the data, and create an intensity plot to visualize the magnetic field. It was a fun project and it worked!
We used a couple old printer stepper motors we found in the lab to control the x/y gears, and had to tinker with them to figure out the proper firing sequence. The Hall Effect probe is a handy little chip that my friend found in a catalog. The Etch-A-Sketch was our brilliant "light" bulb moment when we were trying to figure out how to build an x/y stage with very little time and equipment. It worked pretty well, but the strings inside the toy do slide a bit and thus the stylus does not return to the exact position it started from if you reverse the motor motions.
We programmed a virtual instrument in LabVIEW to control the motors, read the Hall probe, and visualize the data.
Here is a photo of our fun device:
Here is a photo of the magnetic field from a refrigerator magnet, and from two horseshoe magnets. Not everyone knows, but the domains in a fridge magnet are striped, which is why the field is so weak on the front side of the magnet.
