WebTruck Moving out

How to build controls with a microprocessor

at the beginning of this project the was a toy crane operated by a wired control.

After some tests in the productivity lab I started to plan the remote controlled crane.
H Bridge for DC motor

I needed controllers for the 3 DC motors. I decided to use 2 L293 as they provide each 4 outputs - enough for the motors and some other device.

IR interruptor Load Detect There was also a need for sensors to detect end points for rotation, the trolley and the hook.
connect crane to microprocessor these sensors and motors needed to be connected to the microcontroller. Lots of wires to connect...

sensors and microprocessor were ready by end of 2003

after the electronics had been completed, I had to write several pieces of software

  • Stamp Software to control the crane hardware and connect to the serial port (crane.bs2)

    this program controls the 3 DC motors, the servo to position the camera and reads the sensors. there is not much ram in these stamps, so it is not much calculating going on in this program

  • Crane server to get commands from the network to the serial port and results back

    the crane server keeps contact with the crane, logs moves, keeps track of the position and executes commands received from the network. it also provides the video stream and still pictures from the crane camera and runs the motion detection to store pictures in the gallery.

  • Web Server side to server the clients

    glue software to provide crane commands and status to the internet, crane chat to network interface

  • Web Client interface

    controls and results on your browser After intense testing I decided to a Java 1.1 applet to control the crane. It implements

    • video stream

    • controls for crane and camera

    • position and log

this took place in January 2004, by mid January the crane was online

cranebuilding January 2004


with some basic knowledge about electronics it is fairly easy to convert a wire controlled toy into a web controlled toy.

costs ~ 300 USD

tools needed: a soldering iron

parts: the crane, a few ICs, connectors, switches, wires taken from old computers or computer mice, a stamp board, a computer power supply