Today we completed hardware and software for an electronic flow controller for our redesigned Em2.
The little box you see here connects to the Em2's pump and controls flow in the model.
And it automatically runs hydrographs! Teachers and students can run standard hydrographs or program their own, and observe/measure results in the model.
The controller uses an open-source Arduino microcontroller. It's physically hackable--those screws on the front cover are for you to remove, and the cover is transparent for a reason. The software is open source and very accessible.
Via a USB port you can connect it to a laptop to receive data, control flow real time, or program the Arduino. You can control other devices, such as a camera taking time-lapse photos. There are many possibilities.
More later; here we celebrate our first digital hydrograph. And I've done a quick video description.