keeping your pi cool

An average computer’s operating system maintains some logistics about the cpu, like its input voltage, temperature and the like. The Raspberry Pi single board computer is no exception and will even scale back its speed if it determines that its internal temperature is getting too high. That’s a good thing but another approach is to proactively cool the cpu with a fan when it’s approaching that threshhold.


Since I’m creating a cube-like chassis to hold four of these Raspberry Pi 3 computers, I’ll soon need this functionality. So I’ve just created a new repository with JavaScript code to return the cpu’s temperature in fahrenheit/celsius as a string or a number. One could then programmatically turn on/off a fan using the GPIO pins using this information.

Here’s that repository:  raspi-temp

robotics and you

I’ve kind of gotten into a robotics kick lately while looking for cool projects and thought I’d share some of the information with you.  We can probably thank Fab Lab for the motivation since I stopped by there recently for a visit.

I think I’d like to make a remote-control tank with an additional autonomous mode in which it drives itself.  I’d probably put a webcam on there, sensors… not sure, really.

I’m thinking that the closed ecosystem could use a shrimp pellet (food) dispensing system.  I do worry though that one of the shrimp is getting bigger and more of a bully around feeding time, for what it’s worth.  <_<

I’ve also been thinking about a re-breathing device which recaptures the moisture lost when hiking in the desert.  I’m guessing that some sort of breather like scuba gear could additionally inject moisture into the incoming air in such a way that the hiker doesn’t suffer the effects of dehydration.  Unlike the stillsuit of the Dune movie fame for recapturing sweat, I’d suggest that most water is lost by someone in the desert due to the humidity of the air we’re breathing out.  As each new dry breath is taken in, this normally is a very effective means of drying someone to their death, if you think about it. So this invention would presumably avoid this normal loss by trying to recapture that moisture or merely to insert back what is normally lost in the process.  I’m thinking that a system like this might introduce enough water through the bloodstream via the lungs that drinking wouldn’t even be necessary.  Taking this another step, what if you could introduce sugars and nutrients into the mist?  If you google “parenteral nutrition” you can see that someone can be fed intravenously through an IV.  You’d have to balance pH, osmolarity and lipid content of the “food” (glucose, protein and lipids) to make this work and it would need to be sterile.  Something to think about…

So, another trip to Frye’s.  Here’s what I snagged, along with some follow-up research.


There’s an awesome company named OSEPP which makes Arduino-compatible robotic parts, accessories and even kits.  Frye’s Electronics appears to be carrying some of their stuff now which is good if—like me—you don’t enjoy having things shipped from somewhere else.

I just picked up their Tank Mechanical Kit as well as a Motor & Servo Shield and a Motor Driver Module.  I’ve put the tank together and it looks wonderfully sturdy since it’s made out of aluminum for the most part.  Even though it was intended for the Arduino, I’ll drive it with a Raspberry Pi Zero W, probably.  I also got a Joystick Module which I’ll use on a remote, likely a Raspberry Pi 3 in this case.

Tank MotorServoShield MotorDriver Joystick


Frye’s also carries a number of parts by Actobotics which appears to be made by RobotZone (Servocity’s parent company).  They’re likely behind the system of aluminum plates with overlapping hole design often seen throughout these projects.

The demonstration photo on their website was really too big to put here but you can see it if you click this.  So they reasonably have you covered if you’re trying to build anything.  I’m thinking that it must be fun to work there.  I just picked up their 0.1227″ Pitch Plastic Chain for some future project.



Another great company within this space is Servocity.  This company has some seriously heavy-duty linear servo motors.  Someday I’d love to build an exoskeleton robotics project and these would be the servos for that job.  rawr!

Much of what’s being done now in the robotics area involves extruded aluminum channels, beams, plates, brackets and some very polished mounts, clamps and what-have-you.