Dyne's LD-F1 (D-O concept) build

[Dyne]

Since the previous post, I've removed the old neck, and I didn't even need to take off the tracks thanks to fortuitous positioning of the bolts.  As predicted, the pivot on the upper shell was a bit more troublesome, but it wasn't as bad as I thought it might be.  Just a bit tedious.  Taking the old neck off let me test fit the new neck (to the extent possible, given the absolute state of LD-F1's electronics).  

With that done, with Dragon Con imminent, and with the replacement neck nearly ready for installation, I no longer had any excuse to continue to avoid it.  Yesterday, it was finally time for...

The Great Rewiring

I've been putting off the task of cleaning the electronics stuff up for the last 11 months.  This is the mess that I had to deal with:


No more.

The reason I'd been putting it off was, in order to get at the wiring, LD-F1 had to be about halfway disassembled, and I knew that would be annoying and would take me a few hours.  The tracks and track covers had to come off, of course, but also the outer carriers for the bogies (with the cover mounts attached), all four belts, the entire front axle assembly (sprockets, locknuts, bearings, etc.), and the front chassis.  The existing wiring also had be disconnected, ripped out, and redesigned.


As a side note, while I had the droid disassembled, I wanted to take the opportunity to replace that front outer wall that got chewed up last year.  It has somehow been working as-is, but I can foresee a situation where a belt damages it further and causes it to fail completely. So once the front chassis was off, I removed the old wall, transferred the pulley and drive motor to the replacement, and installed it. Here are the two parts.


I also made a modification to the outer carriers for the bogies, opening up a slot in the support for each intermediate pulley's M3 axle.  This is mostly just because I didn't like the axles being completely captive.  This will theoretically make the front chassis easier (though not exactly easy) to remove without disassembling the bogie carriers in the future, at least if you loosen the axles a bit first.



Taking the front main axle off requires chucking the threaded rod into a drill, as it is long and runs through two internal locknuts and a few small bits of plastic along the way.


This is the original main wiring in the front of the droid (with the fuse box removed), as seen from below.  Power comes in from the battery through the top XT60 connector (behind the horseshoe terminal with black insulation) and goes to the switch, then comes out through the white wire with the spade terminal to the fuse panel.  From the fuse panel, it goes to the two motor drivers via the other two XT60 connectors, and to the 5V step-down for the head via the red wire at the top of the image.  The ground wires from those components go back to the brass bus bar, which is the ground rail of the droid, then back to the battery.


With the fuse box removed, this area is much cleaner.  And here you can see the inserts that the new neck attaches to.


This is what the droid looks like with everything removed and the neck attached as a test.  It's a bit fiddly to get the starboard screws aligned to the inserts; they like to miss and push the part up instead.  I'll have to make sure there's no random bits of plastic pushing the neck out of alignment.  It's also awkward to put the forward screws in because the driver likes to hit the side of the neck.  Luckily I have ball-end drivers, so I can turn them at an angle.


All fuses have now been put in individual blade holders (and I added a new main fuse).  The main fuse on the 12V line lies in that electronics compartment beneath the neck, in between the switch and the nearer of the two Wago connectors in the rear of the droid.  Three more fused lines come off of that Wago connector.  The two next to the battery cover supply the Speed Controllers up near the front of the droid.  Routing back and forther adds a bit more length to the wiring but it's unavoidable.  The third fuse supplies the 12V to 5V buck converter mounted beneath the track (visible at right of image) by way of the rearmost Wago connector, mostly just as a convenience so I don't have to solder the fuses or a connector onto the wire.  The black cable here is the one that sends the 5V and ground lines from the buck converter up into the head.  The R/C receiver was also subsequently mounted on the inner wall on the left side of this image using double-sided tape.


The ground side of these three current paths run back to a third Wago connector in the front, which serves as the replacement for that brass grounding bus.  The ground Wago is then connected back to the battery negative terminal.  

The voltmeter was connected across one of the speed controller XT60 connectors and that grounding Wago connector.

The wiring was powered up via the benchtop supply to make sure all the components were working, and I got the reward of hearing the speed controllers use the motors to chime.  The voltmeter near the main switch and the one on the buck converter are both reading values that make sense.

Then came the laborious process of reinstalling everything.  I swapped out the spare intermediate pulley (the one I put on last year when I fixed the chainsaw incident) for one printed in PETG.  I also tightened up the pulleys on their axles

This is what the process for reinstalling the axle looks like.  You have to put it through one side using the drill (seen in the back), while looking through the hole on the opposite side to make sure it aligns with the hole correctly.  That's a bit annoying to do single-handedly.  

The other bits that are annoying to do by yourself are to take the belts off, put the belts back on, and to rejoin the ends of each track.

At any rate, the droid is now reassembled and all of the electronics are hidden within, which is a vast improvement.