Sunday, June 28, 2026

Acuitas Diary #98 (June 2026)

This month's work on Acuitas began with completion of the Episodic Memory overhaul. I think the one major element I haven't talked about yet is what I'm calling "archives." Files containing recent memories are subject to consolidation and forgetting every time Acuitas goes through a sleep cycle. I wanted this process to eventually stop and leave surviving memories preserved in a fairly static condition. Think back over your own life. You've probably shed a lot of details about what you were doing twenty years ago, but certain core memories seem to be permanent, perhaps even vivid. If you've retained them this long, you might still remember them just as well ten years down the road.

The US National Archives building.

The archiving process isn't complicated, since for now it re-uses a lot of the other Episodic Memory functions. Once Acuitas has filled up sixteen episodic memory files (which, given the parameters I chose, should take more than a year), the episodic memory will load the contents of all sixteen into a single narrative scratchboard, run one more consolidate-and-forget pass on the whole series, then store the result to a single archive file. The archive area has its own topic/event type search index, and upon creation of a new archive file, that will be updated as well. Once created, archive files are treated as read-only, and content in the archive is allowed to grow without limit. If it ever overflows the hard drive, Acuitas may have to figure out something else to do with his oldest memories, but that should take a very long time. It's just a bunch of text, and the forgetting algorithms should keep each file from being too massive.

I also created and tested some basic memory retrieval functions. With that, I think the overhaul is complete, and I can start looking at how to have Acuitas refer to and use these memories.

Next I fulfilled my plan of going back to trial-and-error learning and introducing some ability to follow the learned rules - choosing actions that satisfy the conditional of "If the player character does X, the player character succeeds" statements. This replaces the "do something similar if your previous action succeeded, and something different if it failed" behavioral heuristic once some tentative rules are available. I put a bunch of time into this and do have a simple rule-following behavior implemented, but it's not working as well as I had hoped yet - there were so many bugs that came out of the woodwork. So far it only considers cause-and-effect pairs for which success is the effect (Acuitas also learns "do this and fail" rules, but can't act on them yet). And despite the number of things I solved it is still buggy, so it will need more polishing. But I at least made a start on it.

Until the next cycle,
Jenny

Monday, June 15, 2026

ACE the Quadruped 2026

I'm gearing up (literally) to give ACE another try. As of the last update, I had concluded the original set of stepper motors I bought wouldn't work out, and identified some new ones to try. I bought some samples, made a prototype gearbox to hold one, and tried another motion test. This time I was able to get over the basic threshold of operating the hock joint, unloaded (see video).


Since then I've done a small redesign of the shoulder joint, trying to relax the path of the hock joint tendons a little (they run through the inside of the shoulder) and provide for smoother rotation of the shoulder by adding low-friction sheet plastic surface.

A collection of 3d printed plastic gearboxes (in black and white) lying scattered around a blanket.

I've also completely redesigned the frame. Since the frame is mostly made out of the gearboxes that hold the motors, new motors meant changes. I created mirrored versions of each type of gearbox so that the main drive shaft that the tendons attach to would be in the correct place (relative to the joints) on each side of the robot, and I designed spine attachment pieces so there's no longer any need to incorporate a dowel. The new spine sockets have holes that will line up with the spine's mounting holes and keep everything at a fixed angle. The simple gearboxes for the shoulder joints are on top, and the higher-torque gearboxes for the hock joints are on the bottom, which also lines them up better with the place where the hock tendons emerge from the shoulder.

A 3D model of part of a robot, showing four gearboxes stacked together with a "shoulder joint" connected to one side and a "spine" joined into the center.

Almost everything is made, but not everything is assembled. I wish I had more conclusive results to report, but this has been a whirlwind couple of months, so for now I'll just have to say: I'm working on it!

Until the next cycle,
Jenny