Saturday, August 9, 2014

Carl v4 - Carl goes for a ride!

Carl continues to be a hit, but for the last two years I've really been wanting to make Carl mobile.  Standing in one place, waving and giving out Play-Doh is getting old (at least to me).  So I've been looking for a Power Wheels type of vehicle that Carl can ride.

I finally found this electric trike back in February at a yard sale for $3.  What a deal!  It had no battery.  The switch was broken.  The paint was scuffed.  But it was everything I needed and just the right size and after all for only $3 it didn't even matter if the motor worked (which it did)!

I disassembled it completely and cleaned and repainted all of the plastic parts.

Here's what the frame of the trike looks like.  As you can see the steering is very simple.

I needed some way to connect a servo to the steering column so I built a bracket from wood to hold a servo.  My initial mechanism use a pin in the servo arm passing through a hole in the steering bar to turn the handlebars.
 This worked but it wasn't very elegant.  I ended up using my PrintrBot Simple Maker's Edition 3D printer to print a gear that fit around the steering column and a gear that fit on the servo.
I printed a gear to slip over the steering column and another gear to fit the servo.

My printer won't print fine enough to actually fit the splines of the servo.


 So I cut down a servo horn and epoxied it into the printed gear using JB Weld epoxy.

Here's the final steering mechanism.
Next post, the motor controller...