(Random) Copious Free Ideas

A few random ideas for someone's Copious Free Time: (All of these projects involve very low power circuits -- the idea is that these things will run a long, long time without changing batteries).

Cold Bot

Augment a Roomba (or iRobot Create) with a temperature sensing parasite that navigates the Roomba to the coldest spot(s) in a room. If the temperature sensor was mounted on a small probe/arm, then you could pin point insulation leaks. The parasite also controls the power to the roomba thereby extending runtime by shutting the roomba off when the coldest spot has been reached.

For extra credit, make it a warm bot, place a gold fish bowl on top and let it take the fish to the warmest part of the room ;-)


Temperature Throwies


Tape a MSP430F2012 to a coin cell battery and use the internal temperature sensor to log temperature data to its internal flash. Make a bunch of them and place them in parts of the room or house that you are interested in monitoring for temperature trends. Create a single wire interface (data) to transfer data to a collector. The collector has two probes (ground and data) that you touch against the sensor in order to transfer logged data (along with an associated sensor ID).

Plot collected data on a PC.

Mom, my little sisters are messing with my stuff!

Couple a tilt sensor (accelerometer) with an MSP (or AVR) to make a small alarm. Use a piezo buzzer and coin cell battery. Make it small enough not to be easily noticed. Put on top of (or inside of) the item you want to monitor. If someone moves the item, the piezo screams.... for a long time.

Alternatively: Remove buzzer and use a watch crystal to build a fairly accurate RTC. Silently log the time the item was jostled. Collect this info later with single wire interface.