al scanner covers

I made some new covers from aluminum last week for Nathaniel and the SCUBA scanner. It seems he cracked the acrylic ones when he was putting them back on. I guess he overtightened them. I had had reservations about using acrylic, but lexan was out of his budget. Oh well, the aluminum ones shouldn't crack! His student group is going to phase two of this project. I told him yesterday that I will not be able to go any further with them, but will help as a consultant if need be. I just have too many other things that I should be doing and many things that I feel called to work on. 

scanner: finished

scanner video

scanner: sealed and functioning

We stuffed the scanner battery into the case, routed wires, and tidied up the electronics section of the case. I had to cut down the bracket for the scanner battery mount and shorten the studs as we had originally planned to use taller battery packs. I cut some pure gum rubber gaskets on the laser cutter for the access panel and the rear window. Cherise had purchased a marine grade adhesive that we used to seal/attach the top acrylic panel. I torqued the lid down and watched the adhesive push out around the seam. Cherise and I decided that it might be best to just let the adhesive dry and then come back and trim it. I stippled a power symbol into the case outside just over the location where the hall effect sensor is mounted inside the case and then a small circle where the 300 dpi scan hall effect board is located. We decided we were done and that I would come back and trim the glue in the morning. She left and I was packing up and after thinking about having to come in early, I decided to stay and clean up my studio a bit and then I could trim the glue. I knew I wouldn't be able to sleep if I didn't get some closure from this. I ran some test to make sure everything still worked and then dropped the scanner in Nathaniel's studio for him to be able to take on the plane to Florid today. He will be diving in the Florida Keys and doing test scans of coral reef formations. The scanner is now out of my hands! I hope all goes well!

scanner: hall effect ring

I quickly made a ring that Nathaniel can use to trigger the hall effect sensors on the scanner. He can wear this on his hand and then wave it in front of the scanner case to turn the scanner on, and then take a 300 dpi scan. The ring has a small magnet that sits in the top. I used a small steel cap head bolt to connect the top "setting" housing to the base ring, so the magnet wants to stay in the "setting" because it's attracted to the steel bolt. The bolt is threaded into a small hole in the ring.

scanner: sealing/ hall effect sensor

I worked on sealing the scanner case yesterday. Cherise came in to wire the hall effect sensors that I had purchased to use in conjunction with the Rasberry Pi.  The hall effect sensors would trigger (aka:"switch") the scan button and the power to the scanner. The hall effect sensors work by using the magnetic field to trigger the switch. I had been reading about people building diving lights from mag-light flashlights and came across the boards above. It seems standard push button switches can be depressed from the pressures of deep water diving. I was hoping we could find a way to trigger a switch inside the scanner box, and yet not have to have anything protruding into the box to enable it. I found the boards above and watched the video where the maker of the boards triggers the switch through 1/2" aluminum. This looked perfect and I had hoped that these boards might solve our problem. I ordered the boards at the beginning of the week and had them by Friday.

Come Sunday afternoon, Cherise was having a lot of trouble getting the boards to work and there was discussion on changing the design out to a standard button. I was reluctant to drill yet another hole in the box to install a button that had the potential of either being depressed due to pressure or having the potential of a severe leak. Cherise called Nathaniel and he came in to look the circuit over. Cherise had thought that we possibly needed a transistor, and she and Nathaniel finally determined that they needed a relay. After many tests and looking over the circuit many times, they finally got everything right and the hall effect boards worked like a charm. The magnet could be waved over the hall effect board and the Rasberry Pi would then send the signal to the scanner to scan at 300 dpi. I had ordered extra boards so we could control the scanner power with a toggle hall effect board and even possibly make a 600 dpi button as well. After doing some tests with just the one hall effect hooked to the Pi, and having some trouble with the scanner needing a reboot, Cherise and Nathaniel decided that they would wire the other toggle hall effect board to control scanner power. I was happy to see that as I had been envisioning this all along and thought this would be a really great way to have total control of the scanner while under water. We got everything working properly and then we were ready to seal the case.

scanner

scanner: top plate

I drilled the top acrylic plate so I could bolt it to the scanner box. I drilled countersinks so I could sink the socket head cap screws flush with the top of the plate. I finally feel this piece coming together.

scanner: dry assembly