Sleeker and with twice the firepower, SplatBot Mk II has some obvious improvements over the original. Noticably the water bottles and pumps are on the chassis making the cannon much lighter and more responsive. I've also doubled the storage capacity and pumping power. each pump is individually controlled for multicolour writting. Both videos can be viewed in high quality mode.
The first video is the most recent and is for the purist. Directed from afar :)
He sounds like an excited cousin of R2D2 but this is actually the sonar range readings converted to sound to help test that the sonar is working properly.
The second is my earlier experimentation with video editing software syncronised to some suitable music with our new logo hastily added before uploading :D
The chassis is the same as the original with some meccano supports to hold the water bottles (not shown). The two pumps and a DC-DC converter have been added to the back.
The DC-DC converter is configured as a voltage step up current regulator. This means that the output is a higher voltage than the input and the current is regulated to control the brightness of the LEDs.
The LEDs used are 0.5W 10mm green and white LEDs. They are very bright, in the video's they are turned down to minimum brightness. The white LEDs in the water bottles are for lighting up water that has been coloured with food colouring. Unfortunately the only video with that working was the two colour LMR attempt. The dye had to be very dark to show up well on the sand and did no light up as well as hoped. I plan to do a night video that should be better.
I've attached the code for SplatBot although it's incomplete. The IR tracking routine will be re-written to suit the next sensor design and the LMR routine has been written in a less than efficent manner to make it easier for me to tweak the font. If I'm ever happy with it then I'll condense the code.