This is a printable caterpillar robot with gear wheels and links -kind of tank-like ;) .

This is part a project developed in the UC3M university in which we are designing printable robots.

Here, we have together all the pieces that form this robot, but you can have a look at the different parts pages to see some other people modifications -specially at the links.

Take into account that this is a work in progress.Though this robot works as it is designed now, it can be improved a lot -and this is in what we are working right now. Some of the pieces -in their own pages- are parametrized, while others are still pending.

Designers:

Olalla Bravo www.thingiverse.com/olalla Daniel Gómez www.thingiverse.com/dannynoc

A special thank you to Obijuan www.thingiverse.com/obijuan for printing us the pieces, providing useful advice and remarking us some obvious design mistakes and, in general, leading us into the nerdy way =p . Another thank you also to our other professor Alberto, for his advice,patience and invitations to have some coffee.

Individual pages for the pieces: Gear wheels and links: http://www.thingiverse.com/thing:7209 Chassis: http://www.thingiverse.com/thing:7681 Parametric gear wheels: http://www.thingiverse.com/thing:7794

UPDATE:

We've got a video of the robot in motion!! http://youtu.be/gRsKRrQQHos

Update 4/13 23:52

The chassis now includes four drills in order to hold the PIC with the micro that controls the servos above the chassis. Also, the hole that it had so that some material could be saved has been removed in order to sustain better the PIC.

Update 4/14 14:08

Added the parametric version of the gear wheels that we are using in the design.

Update 4/20 00:28

The comments of the links scad file have been translated into English. I hope this will help to understand better the code and that it will make easier modifications of the file.

Chassis

Parts: -Chassis 1.3.scad: we printed a very similar one to chassis 1.3.stl -U-front-piece: take it from Obijuan skybot chassis http://www.thingiverse.com/thing:4954

The chassis is designed so that the distance of the passive wheel from the motor wheels can be slightly modified at convenience. We thought that it was a good idea in order to make sure that the caterpillar track is tensed.

Wheels:

Motor wheels: rueda_dentada.scad, rueda_dentada.stl Passive wheels: rueda_dentada_arrastrada.scad, rueda_dentada_pasiva.stl

They both have been extruded from rueda_dentada.dxg, the only difference between them is that ones have the wholes made in order to be fixed to the servo and the other ones just have a 3mm diameter drill so we can fix them with screws.

parametric_wheels.scad is the trial of making these wheels parametrizable. The example of use (the one in parametric_wheels.stl) is supossed to be the same wheel as the ones we have mentioned before, but for the moment, those have not been printed or/and tested.

Links:

-eslabonoruga.scad, link.stl

We are using 21 links for each track. We are thinking about putting silicone on the links in order to increase traction -but we are waiting till we have the full two tracks to try it. Another suggestion by scocioba has been using rubbery spry.