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

[Dyne]

Apparently I am incapable of getting stuff done with my droid builds unless I have a con deadline staring me in the face.

My last real update was in post #50 near the beginning of October.  On top of my usual late year activities, a variety of real life issues have been killing my motivation and making me highly distractable, so I made literally no progress between then and the end of January (how unprecedented, I know).  

As it happens, I did make plans awhile back to attend a convention this coming weekend.  Since LD-F1's drive was still nonfunctional at the end of last month, it was time to start getting productive...


The first thing to take care of was getting a replacement 58T secondary belt for the starboard track printed -- without that, droid no drive straight and there'd be not much point in carting him to the con.  I installed the new belt this past Friday and was reminded that it's kind of an annoying process (compared to the smaller 40T belt) because the drive pulley and the outer idler carrier both have to come off.

In addition, I've printed two complete sets of spare belts (the second set mostly because the first set came out stringier than I liked).  I made the later belts slightly thicker for additional strength.


I'd used my spare intermediate pulley at Dragon Con, so I also needed to print more in case another comes apart on me.  I now have three spares and might print another if I have leftover filament, but I'm also considering altering the small 10T pulley on this part to be 12T instead.  This will gear the droid down a little, but that's fine.  The benefit is that a higher tooth count will make the pulley thicker and less likely to delaminate like the busted one did.  The downside is that I might end up needing to design, print, and install slightly longer secondary belts.

I've also tightened the loose servo horn that kept coming off.  Hopefully it will stay attached.  Although now that I think of it, I have no idea if it was centered, so I'll probably need to fix it again.


With the major repairs and necessities mostly out of the way, I decided to do some weathering.  LD-F1 is an exploration/scouting droid, so he gets pretty grungy.  I've given him a muddy brown color with some green hints on the main chassis to imply some slight grass stains.  His tracks also got a small amount of weathering to go with the natural weathering they picked up from the Marriott carpet at Dragon Con (not shown).




While I was at it, I also shortened the antenna by somewhere in the neighborhood of 1.0 - 1.5 inches, added two thin strips of aluminum tape below the orange doodlemabob, and gave the antenna some light grime as well.  The paint didn't stick very well to the styrene tubing because it's neither sanded nor primed, but it'll work for now.


The last thing to take care of was to actually make some progress on the side panels covering the track mechanics, which are the final cosmetic pieces.  I eventually want to list the droid in the Holocron app, and this is a necessary step for that (rewiring so I can conceal the internal electronics properly is the other requisite, but that'll have to wait).  After some tweaking of the designs that I posted back in October, I finally started printing the necessary parts a day or two ago.  

Both of the panel mounts (the yellow parts) have been printed.  You can see the Starboard mount below.  It gets four M4 brass inserts in the positions shown.



Those are used for M4 screws that hold on four countersunk ring magnets.  (The photo below shows them attached with socket cap screws because I need to go buy some more countersunk screws.)



The other four holes (red in the CAD shown in October) are for attaching them to the idler bracket.  This is what the assembly looks like in place.



The external panels also have holes for inserts to attach the matching ring magnets, but I can't show you that because the first one is still printing.  While I can likely get all four sections printed and assembled later today or Wednesday, it's unlikely I'll be able to fully paint and weather them until afterward. (Edit: It warped. Likely due to the level being off kilter and the relatively small contact area. Might be able to heat bend it into shape.)


Also, I pretty much have to work with what paints and parts I already have on hand right now.


This is more a project for after the convention, but I am probably going to integrate the middle joint of the neck and the Electronics Box Lid (cyan part in Post #30) of the droid.  This will make the visible portion of the droid's neck static and mostly eliminate the lower neck stalks -- they take up a lot of space inside the chassis that I can use for other things, and are serving no purpose without an actuator.

Doing this will hopefully also make the neck less wobbly. The rear panel of the chassis will still lift up for accessing the battery compartment and the electronics, but I may add some magnets to keep it from bouncing open when driving. My only concern with the idea is whether the four brass inserts that the screws holding the lid thread into will be strong enough to support the entire moment arm of the head and neck without pulling out of the part or breaking it.

Maybe if I can alleviate some of my real life issues, I'll get some of that done by Dragon Con later this year.

There are a few more items on my medium-term to-do list, in rough order of priority.

• As it stands, the head rotation is on the left potentiometer of my radio while the head tilt is on the left stick's X axis.  I am considering revising the R/C model to swap these.  I'd also likely want to disable the return to center spring on the X axis; the head frequently loses its center, so the control would need to remain where I put it like the pot does. Not too involved but I'm not sure I'll get to it.
  
• Rewire the current fuse setup so I can put the ESCs and receiver inside the droid and cover up the switch, as originally planned.  I have to figure out where I put the rest of the fuse holders that I planned to use.
  
• Moving the ESP32 to the body and setting it up with Penumbra will allow me to run the droid via Bluetooth Nav controllers if I want to, but it necessitates a fair amount of rewiring and coding.
  
• The lower stalk and fuse panel removal and front wiring cleanup may clear up room for the originally intended transducer for audio output in its place but I'm not holding my breath.
  

In the longer term, I eventually would like to redesign the droid's drive wheels.  The belt system is a bit of a pain to deal with (the middle pulley axle is barely secured, changing belts requires disassembling half of the track just to get access, the M3 locknuts don't hold the axle securely, etc).  Maybe I'll put in something like a coaxial planetary gear housed inside the front (drive) pulleys.