Amicus1

Looks to be door rails with tiles on top, attached with a 4 sided snot brick so the rails all point in one direction around the circle.

Congrats!

The "geometrical approach" of splitting up the chain is actually well suited for my use case. I'm using this arm as a fancy forklift for loading train cars in a circle. This means what I'm essentially dealing with is a three-chain system. 1. The base turntable at the center of the track circle rotates the rest of the arm to point at the target (train car, a stack of shelves, etc). 2. The first two joints are a two-bone IK chain in two dimensions, bringing the base of the wrist near the target. 3. The wrist (Akiyuki wrist) then has the job of "canceling out" the angle at which it attaches to the arm, in order to continuously keep the forklift end level. Analyzing this, the first 1DOF chain is very simple, and does not need any kinematic algorithm beyond a P loop. The second is slightly tricky, but 2-dimension 2DOF solving basically comes down to constructing a triangle given three sides, which basic trigonometry can easily handle. The third chain, however, will present more difficulties, at least if the wrist rolls. If it stays in two dimensions it's simply an arithmetic calculation based on the angle of the "forearm".

Hopping on the train because these arms seem to be a common thing to do. I’ve found that for my purposes I can probably work in one section of cylindrical coordinates. The base turntable and everything up to the wrist provides a position in a cylinder (a 2d plane rotated around the turntable) and the wrist is a quaternion in Cartesian. I haven’t actually tried it though.

TIL saw and paint are four letter words. Hmm :)

Thread resurrected. The thing hasn’t been posted in for over five years.

Correction: most 4DBRIX products are now available for make-on-demand. I would not be surprised if the next wave contained the R56 switches.

The 12-tooth and 8-tooth aren’t “supposed” to mesh nicely, but it will likely work well enough.

Inspired by War of the Worlds?

Cool to see the dimensions figure base and the Ninjago Airjitsu pod in the same build!

As the 4DBrix website gets reconstructed, a marketplace framework is being put in place for exactly that purpose.

That use of the crater baseplate as steam is genius!

He was offering print on demand since not many other producers were stepping up. Also for the people who want a guaranteed same quality.

It makes a nice sci-fi elevated railway. The problem is most things that can run on it wrap around the track.

The track is compatible with narrow gauge wheel sets, but the curve is too tight (R12) to accommodate most locomotives, so the best method is train wheels facing inward and running on the outside of the track.