Introduction

This is the second kit on the Robotics shelf. In factories and warehouses, robot arms sort the items coming off a conveyor: they take each one, see what it is and put it into its own box — in neat rows, cell after cell. In this kit you build such a pick-and-place machine: an arm on two servos, a conveyor with a colour sensor and a pusher, and a brain that runs it all. Red items go into box A, yellow ones into box B, each into the next cell; a full box — a lamp and a wait.

  • lesson 1 — a servo: the angle is set by the pulse length, a CD4029 counter and a CD4585 comparator;
  • lesson 2 — the arm: a second servo on the same chips, a base with a table and two boxes; you find nine poses;
  • lesson 3 — the pose memory: pose number → two angles;
  • lesson 4 — the conveyor: a source, a belt, a gate, a colour sensor and a pusher;
  • lesson 5 — the brain on chips: steps on a CD4017, the colour in a CD4013, cell counters — the machine works by itself;
  • lesson 6 — the same brain in one GAL22V10: eight chips become one plus a firmware file.
conveyorcolour sensorbrainlessons 5–6pose memorylesson 3PWM ×2CD4029 · CD4585armshoulder · elbowpusher · gripperPUSH · GRIPboxes A and BFULLA · FULLBK1 K0P3…P0A3…A0 · E3…E0PWMbox fullThe 8 kHz clock and the window counter are shared by both servos; the 2 Hz clock steps the brain
How the machine is built: the colour sensor tells the brain that an item has come and what kind it is; the brain drives the pusher and the gripper and picks the pose number; the pose memory gives two angles, PWM turns them into servo pulses.

What you need

The chips are ready-made: the kit file arm-chips.json, imported into the library with one button. These are real Texas Instruments chips — CD4029, CD4585, CD4017 and others — with the same pin names as in the datasheet. For lesson 6 — the file GAL22V10.json and the firmware brain.jed (how the GAL itself works is in the kit «The GAL22V10 PLD»).

The mechanics — the base, the arm, the table, the boxes and the conveyor — come with the pastes of lessons 2 and 4: like a machine that arrives from the factory assembled. You build the electronics yourself, from the tables.

How big it is

The machine of lesson 5 is 20 chips with 3,190 transistors inside. In lesson 6 the eight brain chips go and one GAL22V10 takes their place — 13 chips, 9,600 transistors (6,932 in the GAL alone).

Mode

Build and check in Fast mode. A servo measures its pulse in ticks of the 8 kHz clock, and in Real the editor cannot keep up: the motors slow down and skip steps.