Introduction

In Eliyahu Goldratt's book «The Goal», plant manager Alex Rogo goes on a hike with a troop of scouts. The column of boys stretches out along the trail, although they all walk at the same speed on average. At a rest stop Alex sets up a game with them: matches, bowls and a die. The game shows the same thing as the trail — and the same thing that happens in his plant.

In this kit you will build such a factory on the canvas and play this game yourself. Five machines stand in a line, and each one on average works on a part in exactly a second — as fast as parts come in. You will put together a panel that starts a shift, counts what is released and what is made, and stops the release by itself after 128 parts. Then you will give the machines a die — and see that a balanced line makes less than it could.

  • lesson 1 — the line and its lamps: the factory on a base, five machines, a «working» lamp above each;
  • lesson 2 — two displays: «released» and «made», two CD4029 counters per display;
  • lesson 3 — START and the shift: release through AND, a stop on the top bit — exactly 128 parts;
  • lesson 4 — the experiment: a shift without dice and a shift with a 1…6 die.

The kit has two halves. The lessons show how the controller works: where every signal comes from and why these very chips. The section «What happens and why» shows what goes on in the factory: what Goldratt saw and what he concluded. And «A little history» tells where it all came from: Olds and Ford's assembly lines, Toyota, Goldratt himself and the rules of the match game.

What you need

The chips are ready: the kit file dice-chips.json, imported into the library with one button. These are real Texas Instruments CMOS 4000 chips — CD4029 (a counter), CD4069 (NOT) and CD4081 (AND) — with the same pin names as in the datasheet.

The factory mechanics — the Mechanics button: the source, the machines, the belts, the sink, and the IR pair from Sensors. All of it is placed on the base by the lesson insert; you do not have to lay it out by hand.

How long

Four lessons. The first three are one Cmd+I insert each, the fourth — two shifts of two or three minutes.