| twitter feed gets displayed on 4x40 splitflaps
Microcontroller: Netduino chip. By the end of November 2013 we need to know how much time & money we need to finish the project
People involved: - Merlijn. created the circuit boards and programmed a part
People to work on the project: - Thijs - Bert - Michael
status: driver boards are ready. H-bridge driver, it feeds +24V and -12V to advance one step. Driver boards tested at 12V. At 12V the driver is not reliable enough to advance the flappers. Boards are 24V compatible. 1 Flapper is 5W. So we can't drive all flappers at once. Driver boards are on an SPI bus. These are connected to a Netduino. Merlijn wrote code & GUI to control the Netduino. Flappers have steppermotors. 1 step moves 1 flap. Unknown begin position of the flappers. You can't check their position. There's some wear on the flappers. It's not certain if we need the position checker to make it reliable. Possible solution is a webcam with OCR to check the position of the flappers. We have to check this with the customer. Wiring all the zero sensors is a lot of work; its uncertain wether they work anymore. 160x 4 wires = a lot. Driver boards are only with SPI expanders.