Derek The Daleks Wheels

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This got a bit complicated so here is some of the work trying to figure out the best way to do this.

First I had to model the Dalek Skirt from measurements taken from the physical skirt.

Next I had to measure up the wheel chair base we have and model that.

Then integrate the two models and see whether or not they would fit together.

Integration Version 1

This is the mating of the Skirt model with the current state of the Wheel Chair base.

Wheelchair Integration Take 1
Dalek Skirt Frame and Wheelchair Intergration 1 Front
Dalek Skirt Frame and Wheelchair Intergration 1 Side
Dalek Skirt Frame and Wheelchair Intergration 1 Side 2
Dalek Skirt Frame and Wheelchair Intergration 2 Back
Dalek Skirt Frame and Wheelchair Intergration 1 Top
Dalek Skirt Frame and Wheelchair Intergration 1 ISO

As you can see things dont look great for fitting together and it looks like the front castors will clash with the body of the skirt. To confirm I modified the castor position so that the wheels were in a nominal "worst case" for clashing with the body for Integration version 2.....


Integration Version 2

Wheelchair Integration Take 2
Dalek Skirt Frame and Wheelchair Intergration 2 Front
Dalek Skirt Frame and Wheelchair Intergration 2 Side
Dalek Skirt Frame and Wheelchair Intergration 2 Side 2
Dalek Skirt Frame and Wheelchair Intergration 2 Top
Dalek Skirt Frame and Wheelchair Intergration 2 Bottom
Dalek Skirt Frame and Wheelchair Intergration 2 ISO
Dalek Skirt Frame and Wheelchair Intergration 2 Bottom Section
Dalek Skirt Frame and Wheelchair Intergration 2 Top Section
Dalek Skirt Frame and Wheelchair Intergration 2 ISO Section

With one castor rotated to 90 degrees to the side and one to 180 degrees, forward . It becomes clear that the existing chair configuration isn't going to work.

Integration Version 3

This version has a space model of the volume swept by the front castors so you should be able to see where a castor might clash with the skirt in any orientation. I also had to try and squeeze things together a bit somehow.

Space recovering steps:

  • Move the castor pivot brackets in-board od the wheelchair frame. (essentially just swap the left and right wheels over and bolt them inside, rather than outside, the frame.
  • Shorten the wheelbase. Move the rear wheels forward on the frame. This effectively pulls the castors backwards away from the skirt.
Wheelchair Integration Take 3
Dalek Skirt Frame and Wheelchair Intergration 3 Front
Dalek Skirt Frame and Wheelchair Intergration 3 Side
Dalek Skirt Frame and Wheelchair Intergration 3 Back
Dalek Skirt Frame and Wheelchair Intergration 3 Top
Dalek Skirt Frame and Wheelchair Intergration 3 ISO
Dalek Skirt Frame and Wheelchair Intergration 3 ISO Skirt
Dalek Skirt Frame and Wheelchair Intergration 3 Top Skirt
Dalek Skirt Frame and Wheelchair Intergration 3 Bottom Skirt
Dalek Skirt Frame and Wheelchair Intergration 3 Top Skirt Section
Dalek Skirt Frame and Wheelchair Intergration 3 Bottom Skirt Section

This looks like it will work. However the shorter wheelbase may be an issue:

  • Making the steering response too lively.
  • May affect stability by moving the weight too close to the rear axles.
  • The inboard castors may make it difficult for the driver to fit their feet in to the Dalek.

Possible solution:

  • Switch to a 3 wheel design with only one castor as far forward as possible.
  • Locate smaller diameter / narrower castor wheels.