The workbench

Think by making.

Small experiments that run in your browser. Pick one. It opens here, on the bench.

Bench 01 / Beneath the interface

How software runs.

Scheduling, compiled code, and search, one small view at a time.

The event-loop explorerpredict the order, then step through it

A little WebAssembly65 bytes, read one section at a time

Find a waythe cheapest route through a grid

Bench 02 / Many hands

Building together.

People and AI change one piece of work. Watch the work stay whole.

A shared ideatwo people, an AI draft, and your review

Who adapts?two agents, one repository, six rules

Main movesone merge at a time, tests twice

Bench 03 / Things in motion

A ball and an arm.

A cricket delivery and a robot arm. Each one moves by a small rule.

Line and lengthbowl one delivery, then ask for a review

Reachtwo joints, one target

Bench 03 / Things in motion

Reach

Move a target. A robot arm with two joints finds the angles to reach it. Then let it write.

Answer

Elbow downElbow up

Show both answers

Use the arrow keys to move the target.

Shoulder 2°. Elbow 68°.

L1 = 120 and L2 = 90 stage units. The hand reaches from 30 to 210 units from the shoulder.

cos θ2 = (x² + y² − L1² − L2²) ÷ (2 · L1 · L2)
θ2 = ±acos(cos θ2): + is elbow down, − is elbow up
θ1 = atan2(y, x) − atan2(L2 · sin θ2, L1 + L2 · cos θ2)

Now x = 150 and y = 90, so cos θ2 = 0.375.

What this shows: Inverse kinematics starts from where the hand must go. Most targets have two answers. A target past both links together is out of reach.
Honest note: A flat arm with two links and no joint limits. Real arms have more joints, limits, and weight.

Next on the bench: The event-loop explorer

Back to the bench ↑

Field noteshow the workbench works

The experiments run locally in your browser.
Small enough to inspect.