Update: IR remote function use Arduino Nano addition added. https://www.thingiverse.com/thing:2565293
Update: Instructables published.
Functional battery powered motorized locomotive compatible with Lego Duplo train track and rolling stock. Modelled after the diesel locomotive in LEGO® Duplo Deluxe Train Set with Motor 2933 (1995 - 2004).
The cabin is compatible with the original Lego part and can be used as replacement part.
See the little train in action:
Video 1 and Video 2
TT electric motor with gear box 1
3xAA battery holder x 1
8x8x13mm 6 Pin DPDT Mini Push Button Self-locking Switch x 1
M3x30mm screw x 2
5mm LED (with 500 ohm resistor) x 1
M2x10mm self-tapping screw x 10
M3x46mm steel rod x 1
30x2 mm rubber O-ring x 2
Warning: Not recommended for children 5 years and younger.
All the electric parts are available online. The rubber O-rings are fitted on the drive wheel to increase traction. I bought the rubber O-ring at the local hardware store at plumbing section. The front axle (3mm smooth rod) was salvaged from computer CD-ROM and cut to size. LED head light is optional, drill a 5mm hole at the head light position for the LED.