No longer will teams have to stare at a giant analog clock above the referee, we’ve gone digital!
The Sixth Annual Combots Cup is approaching, and with it some new time keeping widgets for the spectators as well as the drivers.
Here’s a peak at what I’ve been working on:
Those are three 7-Segment Display Big Digit Driver kits from Evil Mad Science!
The plan is to remove the decimal points and use them as the colon in the digital clock, e.g. “3:00″.
My experience with the big 7-segment displays has been overwhelmingly positive. They were easy to assemble, all the soldering instructions were clear, and they were easily daisy-chained together. Also, they’re built to plug right into an Arduino (the grey ribbon cable in the picture above)! It’s still to be seen if they are bright enough to be seen inside the combat arena, especially given all the bright lights that are already inside.
Ideally, the giant displays will be put inside the arena for the crowd to be able to see how much time is left in each fight. How we’ll prevent them from getting trashed by some robot is yet to be determined. At the moment they are protected by wishful thinking, hopes, dreams, and rainbows. Unfortunately robots like Last Rites scoff at such things.
I’m also trying to build clocks for each team, so that the robot driver can do a quick glance and see how much time is remaining. I’m attempting to get these 2.3″ 7-segment displays to work, but they are being stubborn and refuse to light up. My problem is probably just a limitation in how much current can be drawn from the microcontroller board.
Speaking of which, the good folks at Farnell let us try out Digilent’s ChipKIT Uno32. Their website has a ton of excellent electronic products available in the US and beyond.
The above picture is a test to see if my shift register was working as intended, which will be daisy-chained to two more shift registers (and their associated 7-segment displays).
You may notice that the ChipKIT Uno32 (seen in red above) looks strikingly similar to your standard Arduino, well that’s with good reason as it’s built with Arduino compatibility in mind! The Uno32 is powered by a 32-bit MIPS processor, has a large number of I/O ports, 5 external interrupts (versus 2 on an Arduino), is compatible with Arduino shields, and can be programmed using an environment based off the Arduino IDE. My only complaint about the board is that it’s advertised as being fully compatible with Arduino code, and I found that to be only mostly true. When attempting to get the push-buttons to work, I was using the AttachInterrupt() function when using an Arduino, however the AttachInterrupt() function was not yet supported by their IDE. On the plus side, that was my only gripe with the board, and their team is continually updating their IDE to be fully Arduino compatible.
Additionally (not shown in the pictures), there will be some relays tossed in there so when the timer hits zero, something glorious will happen.
Airhorns, glitter, leprechauns and unicorns. However, due to budget constraints, airhorns are the most likely out of the bunch.
Thanks again to Evil Mad Science, as well as Farnell and their US team!
