I recently handed these off to a psychology grad student who is measuring response time for some sort of interactive audio/visual task. These are basically USB keyboards with fewer buttons and the ability to report their timing delay.
Inside each one is a Teensy LC and some Cherry MX "clear" keyswitches. Keycaps are from here.
Somewhat late in the process of building these I was asked to add a capacitive switch, which the TeensyLC handled well due to its touchRead() capability. The capacitive "button" is a wire attached to a 2-56 screw.
The per-unit cost came to around $22 USD, which is much better than some (all?) of the alternatives marketed for psychological research purposes. Because of the low cost, their budget allowed me to build a total of eight 4-button boxes and two 8-button boxes, which is enabling them to get more subjects per day, and therefore more data to analyze.
Guts:
Entire open-source (hardware and software) project is available here:
https://github.com/hoosierEE/psych-button
Inside each one is a Teensy LC and some Cherry MX "clear" keyswitches. Keycaps are from here.
Somewhat late in the process of building these I was asked to add a capacitive switch, which the TeensyLC handled well due to its touchRead() capability. The capacitive "button" is a wire attached to a 2-56 screw.
The per-unit cost came to around $22 USD, which is much better than some (all?) of the alternatives marketed for psychological research purposes. Because of the low cost, their budget allowed me to build a total of eight 4-button boxes and two 8-button boxes, which is enabling them to get more subjects per day, and therefore more data to analyze.
Guts:
Entire open-source (hardware and software) project is available here:
https://github.com/hoosierEE/psych-button