A miniature power distribution unit (PDU)

A miniature power distribution unit (PDU)

Over the weekend, we built a small Power Distribution Unit for a new robot. We hacked a male Deans connector (which will plug into a high-amp LIPO battery), then soldered it into a marine toggle switch, then screwed it into a device of our own creation. We constructed a miniature power strip with screw terminals to power the various 12 volt electronic components of the robot, such as the motors, Arduino board, IMU, and others. We built it by soldering 8 individual screw terminal pairs to a tiny circuit board that we cut to be just big enough to fit them (about 1.6″ x 0.6″). Then we soldered all the pins on each side together so that voltage will flow down one line and ground will flow down the other. You can see in the picture that we have one small electronic component connected so far. In the past, we’ve just soldered all our power wires together into a big hunk of solder and then heat shrunk the whole thing, but using that approach made it difficult to add new components later on. We think this screw terminal idea will be more flexible by allowing us to add, subtract, and swap components as required.

I don’t understand why some company doesn’t already make a small Power Distribution Unit like this. We aren’t the only ones who need to distribute power to various components. I’ve looked and looked but can’t find anything that’s even close (i.e. small), which is why we decided to build this one ourselves. If anyone has any better suggestions, or has a source for small terminal strips for distributing power, please let us know.

We also built a second screw terminal strip that was even smaller (1″ x 0.6″) for powering up to 8 lower current devices, such as the various 5 volt electronic components. See the pictures of the small green device below, with views of the top and bottom. When we did the soldering, I asked Genevieve to create two long caterpillars of solder along the row of pins. I think she did a very good job.

Building a couple of PDUs is a humble beginning, but every robot has to start someplace. 🙂

Genevieve building Power Distribution Unit

Our homemade mini Power Distribution Unit


Top Side View of our mini low-amp Power Distribution Unit

Underside view of the mini PDU showing Genevieve’s soldered “Caterpillars”

Remote Control

Remote Control

We have been hard at work on our latest project called Mechatron. To control our Mechatron robot as well as our Mars Rover, we designed and built our own remote control box. We developed our own communication protocol for transmitting commands from the remote control to the robot. On other projects we used iPhones and Playstation remote controllers, but in this case we wanted to build a large, metal box with lots of retro-switches and joysticks.

Remote Control Box for our Mechatron Robot

Inside wiring for the Mechatron Remote Control


Technical Details

  • Microcontroller: Arduino Mega 2560
  • Remote Control Software:  Beatty Robotics
  • Design and Construction: Beatty Robotics
  • Box: Aluminum sheet and metal screws
  • Radio:  xBee Radio module
  • Joysticks: Digikey x-y-z-axis, hall-effect, 1 button joysticks
  • Rotary LED Encoder Ring: Mayhew Labs
  • Battery: 12v LIPO
1. Although it wasn’t cheap, the hall-effect 3-axis joystick was critical for controlling the function of Mechatron’s specialized drive system. We originally tried a traditional analog/resistive/potentiometer-style joystick and it did not work well at all. We thought our whole project was going to fail until we realized that not all joysticks are created equal. The joystick based on the “hall-effect” principle worked perfectly for us.
2. You can’t see it in these photos, but this controller can be charged via banana jacks and re-programmed via a USB jack without having to unscrew and remove the case. The same is true for the Mechatron robot itself.