Kansas City Maker Faire: Pi-Plates

As soon as he spied the Jolly Wrencher on my shirt, [Jerry Wasinger] beckoned me toward his booth at Kansas City Maker Faire. Honestly, though, I was already drawn in. [Jerry] had set up some interactive displays that demonstrate the virtues of his Pi-Plates—Raspberry Pi expansion boards that follow the HAT spec and are compatible with all flavors of Pi without following the HAT spec. Why not? Because it doesn’t allow for stacking the boards.

[Jerry] has developed three types of Pi-Plates to date. There’s a relay controller with seven slots, a data acquisition and controller combo board, and a motor controller that can handle two steppers or up to four DC motors. The main image shows the data acquisition board controlling a fan and some lights while it gathers distance sensor data and takes the temperature of the Faire.

The best part about these boards is that you can stack them and use up to eight of any one type. For the motor controller, that’s 16 steppers or 32 DC motors. But wait, there’s more: you can still stack up to eight each of the other two kinds of boards and put them in any order you want. That means you could run all those motors and simultaneously control several voltages or gather a lot of data points with a single Pi.

The Pi-Plates are available from [Jerry]’s site, both singly and in kits that include an acrylic base plate, a proto plate, and all the hardware and standoffs needed to stack everything together.

Talking Car Automation Computer is like KITT without the Sass

It’s a wonder that drivers are given so little insight into what’s going on under the hood. We mostly have the illusion of insight in the form of gauge, idiot lights, and when things get real, our eyesight and sense of smell. The older a car gets, the more important it is to be aware of the condition of its systems.

[Mjtrinihobby] drives a beat-up 1999 Honda Civic. He likes creating automation systems as a hobby and figured that his car would make an excellent test subject. [Mjtrinihobby] began this project with several features in mind. He wanted more control over several of the car’s systems—the A/C, lights, the fuel level, and the blower motor in the cabin to name a few—and a compact, user-friendly way to interface with them that could handle road shock and the heat of the climate he calls home.

He chose a Windows 8.1 netbook with a touchscreen display for the user interface. The netbook is running FlowStone, which is a robust graphical programming language with a long list of applications. A LabJack data acquisition board (DAQ) handles the communication between the car’s systems and the netbook.

This is much more than just a cool way to control the climate and make the headlights come on when darkness falls. For instance, [Mjtrinihobby]’s system continuously monitors the alternator’s voltage. If it measures between 7 and 12V, a friendly voice warns about possible alternator failure and disables high-draw accessories so the car has a fighting chance of making it to the mechanic.

Be sure to check out the demonstration video after the break. If OBD-II car hacks are more your speed, try building an RGB tachometer.

Continue reading “Talking Car Automation Computer is like KITT without the Sass”

ATtiny85 Data Acquisition


The folks at Ivmech recently had a need for some new hardware. They needed a small, cheap device able to sense some analog values, toggle a few digital pins, and log everything to a computer. What they came up with is the IViny, an extremely small data acquisition device built around the ATtiny85, capable of logging data to a computer.

The IViny features two digital channels and two 10 bit analog channels, just like you’d find in any ATtiny85 project. Power is supplied over USB, and a connection to a computer is provided by V-USB. There’s also a pretty cool Python app that goes along with the project able to plot the analog inputs and control the digital I/O on the device.

It’s not exactly a fast device – the firmware only supports 100 samples per second, but an upcoming firmware upgrade will improve that. Still, if you ever need to read some analog values or toggle a few pins on the cheap, it’s a nice little USB Swiss army knife to have.