The Super Walker

Description

The Super Walker

Introduction:

The handle bars on this walker go up and down on 2 track actuators. They're like Aero Bars on a road bike. I can lean on them and it stands me up.

Here's the first gen in action: https://www.youtube.com/watch?v=dR0FWT_xHMU

First generation design: I used 2 Mini Track Actuators from Firgelli Automations to do the lifting. I powered it with a 12.8v 6.6Ah Lithium Iron Phosphate (LFP) battery.

The little actuators just weren't up for the challenge and kept burning out. Plus they had two separate motors so it was always getting out of balance and would bind up.

For the 2nd generation we used a chain drive powered by a power window motor. It worked great but had a fatal flaw: if the chain breaks then the whole thing will collapse.

So currently I'm working on the 3rd generation: Custom ACME screws with 3D printed carriages and bearing blocks powered by a single motor.

Project Logs

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Gen 2 - Chain Drive
Drew Shelley • 08/10/2014 at 04:34 • 0 comments

We set out to redesign the walker. My dad had some Harken travelers from a sailboat to use as the track and linear bearings. I found a power window motor and ordered some XL timing belts, pulleys and bearings from McMaster Carr. We built the walker with one motor driving both pulleys and belts to lift the handlebars. But the timing belts kept slipping. Also, the quarter inch driveshaft was too flimsy. We changed the design and switched out the timing belts for a chain drive and larger drive shaft. Then finally it worked!
But this design has a fatal flaw: If the chain breaks, the whole thing will collapse. I needed something better.
Gen 1 - Mini Track Actuators
Drew Shelley • 08/10/2014 at 04:24 • 0 comments

Last year we built this super walker with Mini Track Actuators from Firgelli Automations.
http://www.firgelliauto.com/product_info.php?cPath=104&products_id=259
It worked great at first. I could sit and stand anywhere. We even built a second walker with the same mini track actuators.
But those little actuators just weren't up for the challenge. They kept binding from the leverage on the carriages. One was always faster than the other because there were 2 separate motors with no synchronization. Plus the little motors were too delicate and kept burning out. In the end, 3 out of the 4 actuators failed.