A motion-tracking eye, derived from http://code.google.com/p/theeyestheeyes/, on a walking chassis.

Here's the second test run, using parts designed in CamBam: http://www.cambam.co.uk/ and cut from 3 and 6mm acetal sheet:

More photos:

http://picasaweb.google.com/jarkman/100307_spider#

CamBam and DXF files are available in the Downloads section. The latest design (mk4) eliminates a possible lockup in the linkage, and has a larger backplate that makes it harder to get your finger pinched by the cogs.

The walking action uses the Klann linkage: http://mechanicalspider.com Specifically, configuration E006.

The motors are Solarbotics GM17, from Technobots, which will generate a decent torque from 5v upwards, and a nicy scurry at 12v.

Pivot bolts are all M3x10 and x14 button head allens (MF-BH34S et al) & nylocs (MF-NN03S), from http://modelfixings.co.uk. Plus a 44mm bit of M3 studding.

The gears are held onto the shafts with No.2 (2.2mm) by 6.4mm and 9.5mm self-tappers (MF-ST09).

Motor mounts are M2.5x20. Gears are mod 1.5, 30mm pitch circle, 14.5 degree pressure angle. They're designed with CamBam's cog tool and cut from 6mm acetal sheet.

Acetal is from http://www.directplasticsonline.co.uk/ The sheet thickness is a bit variable, so if you use our CamBam files make sure you adjust the cut depths for the sheet you have.

This project was inspired by this cute little thing:

http://hackaday.com/2010/02/03/lego-spider-bot/#more-21410

And it has children!

See Tom's MechaLobster here:

http://sites.google.com/site/corerobotic/main-projects/mechalobster

and Andy's SonOfCrabby:

http://www.youtube.com/watch?v=skwF7IdNPIw

http://picasaweb.google.co.uk/10bulls/SonOfCrabbyKlannBots?feat=directlink