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Ok so my belt drive system from my last update just is not quite up to par in terms of grip and anti-slippage. So my new series of changes are planned out and underway now. First, I will be bumping up the height of each pulley to 2mm up from 1.1mm. This will double the surface contact area for...

Ok so I was struggling to plan out how the flat spiral coil constant force spring would maintain constant tension on my first winch in place pulley the past couple days and I was studying how tape measures use these springs. Then it hit me when a colleague was mentioning belt pulley based...

Here's a better image of the grooved outer race with more refinement. To refine it I cut away excess glue with exacto knife and then sanded it with a nail file a bit to smooth it out.

Ok so I've been now working toward creating the latest iteration of the Archimedes 16:1 pulley based downgearing system and as part of that I decided to remake some of the pulleys with grooved outer races as I had discussed previously wanting to do - in order to prevent the fishing line from...

Okay so here is my latest iteration of my motor mounted winch in place pulley downgearing setup completed. I ended up doing a total overhaul of everything since my last iteration failed. In this iteration I made many small improvements. One thing I noticed is that the thumbtack shafts have a...

This is a slow, careful hand test of the pulley. Everything looks good. Also, I did fast tests but didn't capture a nice shot of those with good hd closeup like this. In any case, this can show you some idea of how it all looks in action so far. The motor shaft is not turning electronically but...

Note: I could do the rotate in place style pulleys but just put them on the forearm instead of the motor as the motor is already getting quite cramped and tedious to work with. Or I can do Archimedes pulley system style with pulleys that move lengthwise along the forearm. Both styles are good. I...

I managed to implement a friction device for both main manual input pulleys for manually turning the motor shaft and one for creating tension on the system at all times. The former I made by just running the fishing line through a tension spring between the coils which pinched the fishing line...

I started some testing on just the first pulley and lots of things went wrong: Twice I had to increase the pulley size because I wasn't able to use enough line winding onto said pulley for my total line draw need after accounting for the 32:1 downgear ratio. I calculated 27" as the very least...

So it turns out that when the forward and reverse directions portions of the thumb tack pulley downgearing system are doing their thing, they won't always have the same mechanical advantage and so will be moving at different speeds. Therefore, I have to treat the forward and reverse pulley...

I wound up my 6lb test Hercules PE braided fishing line onto the previous pulley system setup only to find out that the pulley could only handle about 21 inches of fishing line wound onto it before it started to come dangerously close to overfilling the pulley. The aim is to have plenty of the...

I got done cutting out the pulley discs and drilling them and mounting them to the thumb tacks and gluing them in place with 401 glue using a sewing needle tip as the applicator. They all are reasonably square and solidly in place I think. Everything is moving freely. Everything seems lined up...

Here is a progress update on the silent pulley downgearing system I came up with using thumb tacks and a #2 fishing crimp sleeve and little plastic discs. It is some tiny fine precision necessary work but I'm getting it done and things seem to be looking pretty good so far. For now, I ended...

Okay, so I finally got the Dinah robot hand sewn in and it is looking pretty good. The fingers could use some tweaking but overall I'm quite happy with how it came out. It's solid and fully articulated. Here's a photo of it in place: Now that out of the way, I want to announce I'm...

I'm currently working to sew all the finger and wrist bones together for the Dinah robot and mount them to the arm. I wanted to show how I'm doing this process. Here I tape the bone with adhesive transfer tape 3M 300 LSE. Note that I leave space on either end of the bone to allow some free...

So I finally got the wrist done. And aside from grinding off welds on bolts and backing off the bolts to allow for free movement at joints, I'm mostly going to try to keep this skeleton stock for the most part. So I may be attaching the hand and going immediately into electronics rather than...

In these photos you can see the progression of going from the stock wrist to an axial rotating wrist assembly acting as a plain bearing. Pardon the Orgrimmar welding - it's a cheapo welder. The process involved cutting the bolt head off then grinding smooth the threads and then...

I managed to get Dinah's hand bones printed out in ABS on my Anet A8 3d printer the past couple days. I also cleaned up the prints, removed the supports, and sanded down high points. They are ready for attaching them together with cloth tape which will act as artificial ligaments. You'll note...

The Dinah robot is coming along well. I modeled the full steel skeleton in CAD to match the dimensions of the Dinah base mesh and created a human bones variation as well to compare that to the steel simplified skeleton and make sure all the joint pivots matched the locations of the human...

I just came up with a cool alternative way to downgear a 2430 BLDC motor that might work. Here's a illustration of the cheap downgearing idea: So basically, I figured what if I could remove the N20 motor from its gearbox/"gear set" by cutting it free or w/e. But I keep its center axle in...