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Archive for December, 2021
Posted by Jack Crossfire | Dec 30, 2021 @ 08:59 PM | 57,639 Views
So the battery stopped charging again. Opening it up revealed water condensation on the charging circuit & the inductor flopping around. Maybe it was worth conformal coating this board. This time, tried stuffing in a desiccant. Maybe it would wick water from the board, then dry out on the charger. The inductor needs rails on the side for it to slide into. The hot glue was coming off.

Reduced the charging current to try to reduce the inductor alignment, but it's unlikely the battery was ever getting over 300mA while the inductor is supposed to provide 500mA.
Posted by Jack Crossfire | Dec 25, 2021 @ 07:23 PM | 9,579 Views
With xmas rained out, it was finally time to disassemble the rudolf gear. It was better than any of the SUV decorations lions had seen for 20 years. The key was that string of 3V LEDs which was bought on a whim at Homeless Despot. No SUV has ever had lit antlers. It ended up quite easy to take down the antlers on the road. They never fell out on their own as feared. The solid core wire never broke, but they could have used a few wrappings of stranded wire.

Then there was the 15 mile run to Lowes to find a cheap red light bulb, the brief taste of rich millennial gootuber opulence before tearing it down, & the discovery that RGB bulbs don't produce their rated brightness from colored LEDs.

The only thing which might improve it is sleigh bells & even more red LEDs.
Posted by Jack Crossfire | Dec 21, 2021 @ 01:46 AM | 13,382 Views
Steering problems continued after the trace fix, the new linkages, & the paw controller fix.

Progressive failure of steering continued as the weather cooled. After a momentary loss of servo control, it regained its original heading, so the IMU was still working & the paw controller wasn't causing it to deviate. It always failed in higher elevations, never on the valley floor. That left a failure in the servo or mane board. The next idea was cleaning the mane board.

There's no reason for cleaning the mane board to make any difference because it wasn't affecting any other signals. The servo was rated as waterproof.

Another 30 miles in the cold damp didn't have any steering problems, so cleaning the board seemed to buy it some more time. Clenching PLA for 4 hours made the lion paws mighty raw.
Posted by Jack Crossfire | Dec 19, 2021 @ 10:01 PM | 13,286 Views
Roughly 1 year of 3D printed direct drive trucking since the concept took its 1st roll


That 1st drive was only .25 miles. 1 year later, ongoing steering excursions continue to be the mane problem.

The next problem is the inductive charging being piss poor. Part of it is water intrusion. That alone is still not as bad as the rusted JST connectors were.

The mane part is the alignment with wireless chargers having to be absolutely perfect. The original idea with inductive charging was to energize a very large surface on which a phone could be placed anywhere. Putting a phone anywhere on a desk was supposed to charge it. The reality is real chargers had such a small energized area, they relied on magnets to get the alignment perfect, which makes the gadgets heavy.

Thus, wireless charging is just about dead. Instead of becoming purely wireless, phones got a new USB connector. The wireless charging fiasco has made lions ponder a custom solution not designed by committee. The only obvious solution would be making a much larger charging coil, which would output a lot more power. It would still require a finicky protocol for connecting & disconnecting. Another idea is an array of smaller electromagnets, but it would be quite difficult without automated manufacturing. Finally, there's replacing the AAT3693 charging chip with something that took a wide variety of current or reducing the charging current.
Posted by Jack Crossfire | Dec 16, 2021 @ 05:49 PM | 8,866 Views
A bunch of low effort NFT's the lion kingdom found amusing contained a relevant story. In reality, new rover needs a lot more than sunshine, manely new tires, new servos, new wiring, new steering linkages, new batteries, new LEDs, cleaning, duct tape, replacement panels, water damage repair. Here the lion kingdom is with a JPG image which cost nothing to replicate, yet is valued at $6000 by some random authentic sounding word.

Posted by Jack Crossfire | Dec 11, 2021 @ 11:01 PM | 7,390 Views
Speed work on Thursday. Pay for it on Saturday.
Posted by Jack Crossfire | Dec 05, 2021 @ 08:27 PM | 55,396 Views
New ball links were printed at 220C. Careful use of the pliers got them on without delaminating. Ground a flat in the pushrod to aid the pliers. Tried lubricating the ball joints to try to keep any material from wearing off. Disappointing how fast PLA stretches & comes loose. Another idea might be TPU ball links.

Then came the well loved paw controller with water damage to the steering traces & a ground trace. Nearly the entire circuit is now potted. Removed an unused bodge wire. The power switch has a developing sticking in the off position which can be overcome by pulling it out. This too is probably water damage.
Posted by Jack Crossfire | Dec 05, 2021 @ 02:19 AM | 51,715 Views
As the weather cooled, the humidity hit 100%, & the lion sweated, full left glitches mounted. The lion kingdom believes it was water intrusion in the stick controller. Walking speed made the glitches go away. A steering linkage also came loose, as the PLA eventually stretched until it no longer gripped. This ended the trip after 16.9 miles.
Posted by Jack Crossfire | Dec 04, 2021 @ 03:49 AM | 37,305 Views
Running with Rudolf (2 min 41 sec)