The rear VW emblem on the golf serves a number of purposes:
#1 – It’s an emblem.
#2 – It’s the latch and handle for opening the rear hatch. Pushing in at the top of the emblem causes the hatch to unlatch and the bottom of the emblem swings out to use as a handle for lifting.
#3 – (what this is all about) It’s a back-up camera. When in reverse, a small camera is pushed through a trap door behind the emblem causing the emblem to swivel up. The golf’s controller knows not to unlatch the hatch if it see the emblem swivel while in reverse (because it’s the camera that has swiveled the emblem, not a person).
Having a backup camera on a car that I can practically lean back and touch the rear windshield from the driver’s seat doesn’t make a lot of sense, most of the time. I have gotten used to it though – it’s great for towing and I have lines on the garage floor that allow for precision parking every time, maximizing usable garage space. A few weeks ago the camera stopped working; I investigated further and found that one of the arms of the extension mechanism had broken off. At that time I grafted a sheet metal strap onto the plastic mechanism and melted parts of it back together. This lasted a about a week, so this weekend I re-produced the entire plastic part completely with steel.
During the many cycles of assembly and dis-assembly of the camera mechanism I encountered a problem where any time it was put into reverse the hatch would open! This is kind of a funny outcome since it’s still fulfilling the purpose of more visibility when in reverse, just in a different way. This would be inconvenient, to say the least, so I tracked the problem down to some frayed wire connections. The shorted connections caused the hatch switch signal not to be ignored when the camera was deployed; re-terminating the wires fixed the problem completely.
Lots of yard work lately, the tilling and composting last spring definitely seems to have paid off and grass is finally growing even in the shadiest areas. The bus was enlisted into the effort as plant transport, and we also picked up a big landscape boulder. A big spider joined in with guarding the garden hose, see brick for scale.
This week I was in Atlanta for a conference at Stone Mountain. We hiked to the top after dinner one night, I got some OK pictures from the top….
Today I completed the “long cross-country solo” part of the the private pilot requirements. I made a big triangle over the middle of the state with legs of 104, 61, and 56 nautical miles. Along the way I spoke with approach control of two different class C airports, everything went great.
This afternoon I completed the controlled field solo take-off and landing requirements; 3 take off and landings to a full stop. There’s plenty left to learn but altogether this went fairly smoothly; some of the intimidation factor is now gone and that will be a big help for future flights in controlled airspace. Here’s an old photo of the airport (guess which) where I did this:
I may have only a handful of flights left prior to the checkride: a night cross country (dual), a long solo cross-country, some more practice, and then the mock checkride.
The weather is warming up and I’m anxious to start driving the bus again. Since the last trip prior to winter ended with stalling I put the bus up on ramps and investigated the problem. Based on the behavior I had suspected fueling problems. I checked the fuel pump and it was OK (though it’s 30years old so I’ll likely replace soon anyways), and also replaced the fuel filter. The old fuel filter was full of rust particles but it wasn’t really restricting the flow. A clue came about during replacement of the filter when I forgot to crimp the fuel hose upstream of the filter. Normally this would mean a shower of gasoline but there were only a few drips, indicating a clog upstream of the filter. I pulled the hose fitting off of the bottom of the tank and found it almost completely clogged. I had cleaned the tank when I had it out for repainting but it doesn’t take much to cause a clog. Now that it’s being driven the gas is sloshing and continuing to clean it out further. I’d expect the worst of the gunk has passed through by now but I’ll have to check this fitting periodically.
The first night flight was tonight, I arrived a little early and had to wait for sunset. Things looked very different but overall it wasn’t that bad.
After cancelling many flights due to weather I finally completed my first cross-country solo this weekend. 56NM from wheels up to touchdown. 4500FT on the way there, 37min. 3500FT on the way back and only 25min, top ground speed was just short of 150MPH.
Next up is night flying, followed by a night cross-country, and then it’s just some practice and review prior to the check-ride. If the end of winter brings better weekend weather I should be able to finish soon.
Tonight I got the machine fully assembled and working with all axes (and the spindle) at once. This greatly improves image plotting since the pen can be lifted. I just need to mount the spoil board and I should be able to begin cutting tests.
It’s been a while since I’ve updated, and I’ve gotten a lot done during this time. I modified the gantry motor plate (one of them at least) to include a spring tensioner and also added some diagonal braces to the gantry columns; the gantry now runs even smoother and with little or no backlash. I then added the Y axis guides, fabricated the Y axis motor carrier and Y rack support. Once I got all the Y parts together I was able, for the first time, to test coordinated motion between axes by clamping a pen to the Y axis. The results of this testing were great. It drew very accurately with the pen, the drawing path even occasionally required overlapping the same pen line later in the program; it was able to follow the existing lines exactly. The only thing it couldn’t do was lift the pen, since the Z axis wasn’t installed…
…So after I eventually finished playing with plotting images I began work on the Z axis. The biggest challenge with this was attachment of the spindle mount; the spindle mount is one of the few metal things (other than the motors/guides/racks) that I didn’t fabricate from scratch; despite this I still needed to do some fairly extensive machining/modification to get it attached to the Z extrusion in a very secure but still adjustable way. With the spindle mounted to the Z extrusion the remainder of the work was just some minor drilling, tapping, and cutting. The Z rack is a lot longer than it needs to be for the amount of travel Z has; it was the last rack section to get cut so the extra length is just the leftover/spare, it fits on the extrusion so no sense cutting it off.
Sometime during initial gantry testing I fried the Z axis motor driver on the smoothieboard when moving the gantry by hand with the drivers off. Z wasn’t even connected during this but my guess is the spinning gantry motors fed back through their drivers onto the supply bus; Z happened to be the weakest and it fried with a snap & flash. Because of this I was actually testing the Z axis with the Y driver. I have an external stepper driver on the way and once it arrives I should be able to move all axes at once and really see what it’s capable of. Next Steps:
#1 – Finish electrical enclosure fabrication
#2 – Modify other gantry motor plate to include spring tensioner
#3 – Final fabrication of cable management, cosmetic covers, etc.
#4 – Disassemble, body work, prime, paint
#5 – Final reassembly & wiring