Collaboration with artist Estefanía B. Flores for her master's thesis at Goldsmiths, University of London.
Old arcade claw crane controlled with an Arduino UNO microcontroller board.
There are three DC motors, but we will only use two.
They seem to be 12V Crouzet DC brush geared motors (828610).
I used an Arduino motor shield to control them.
Each motor has two associated limit switches. They are connected to the Arduino using internal pull-up resistors.
(From this manual)
The claw is closed using a push solenoid.
To control the claw, I used a relay module. More specifically, I used a SunFounder 2-Channel DC 5V Relay Module with Optocoupler Low Level Trigger Expansion Board.
An ohmeter says the resistance across the solenoid is 4.5 ohms, so the current through it will be 2.67 amps, as we are using 12 V. We close the claw for 50 ms.
A flyback diode (1N4007) is placed in parallel to the claw to protect the circuit. According to components101.com, the non-repetitive peak current is 30 amps, so it should be fine.
I decided to leave the jumper between Vcc and JD-Vcc in place (i.e., the current for the relay solenoid is supplied through the Arduino pin). Ideally, though, this voltage would come from an external power supply (good explanation in this video).
For testing, I used the joystick that comes with the Elegoo starter kit. It seems to be a KY-023.
More info:
I use the potentiometers to control the two motors, and the push button to close the claw.
- Holland Computers, Inc. – Crane Kit Manual – Part Number RA-CRANE-KIT
- BBTSON MICROPROCESSOR CRANE
- Coast to Coast Entertainment – Stage 1 Crane Controller – D9803D4 Instructions
- Grayhound Electronics – The Crane Operators Manual
- Grayhound crane dip switch settings
- ArcadeControls.com – "greyhound crane claw problem"
- Hackaday.io – Toy Claw Machine
- Fixing an 80's Drew's Tiger Paw Plush Crane Claw Machine With Schematics
- Arcade Claw Machine/ Prize Game with Arduino
- Powering a crane/claw
- Claw machines are rigged — here's why it's so hard to grab that stuffed animal
- Arduino Claw Machine