Derek The Dalek

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The Hackspace Dalek - AKA Derek the Dalek

We were visiting a pub in Baldock which had a Dalek in it's Beer Garden. We are now looking after it and are going to repair it. Currently most of it is languishing in Mike's garage.

Dalek First Full Assembly CAD Model

What needs doing to get Derek up and running

What sort of Dalek is Derek? Is it a real, as in based on dimensions of a Dalek seen on TV/Film, Dalek? Or something someone has made that was their interpretation? Which "real" Dalek version is Derek closest to?

Check out the Project Dalek Forums and data sources and measure Derek to see so we know what is the closes design to aim for.

After a lot of measuring and modelling It looks like the Dalek is reasonably close to the dimensions of one of the early Daleks. In the Dalek building community these are known as the "Shawcraft" Mk1, Mk2 and Mk3 and also the two 1960's movie Daleks. So that makes the selection a bit easier. Additionally, as we want to put the Dalek on a wheelchair it helps with the motorisation to use the "fenders" used on the movie Daleks. The Fender was introduced to conceal larger wheels as the movie Daleks ventured off the billiard table smooth studio floors in to the rougher and bumpier outside world. For the rest of the Dalek features we are going to pick and mix features from the different models.


Motivation / Locomotion

Paul B has two wheel chair drive chains which needs modifying and installing.

Wheelchair Rear View
Wheelchair Side View With the other Wheelchair Chassis and assorted battery boxes

Battery

What size batteries are required?
What type of batteries? Answer from one of the battery boxes = CXL-42
Need 2 Batteries, both 12V to give 24V for motors.
Something like https://www.mdsbattery.co.uk/2-x-csb-evx12400-12v-40ah-mobility-scooter-batteries.html
Cane & Able may be able to help with some older / used batteries which would be fine for initial testing.

Wheels

Front Wheels are castors = dia 200mm by XXmm wide
Dimensions of drive wheels = dia 320mm by ~80mm wide
Tyre Sizes
(57-203) 12.5" x 2.25" "Innova" Brand Grey rubber - 2 new tyres acquired

Footprint of wheelchair base

Will it fit in the Dalek Base?
Mounting points
Mating the wheelchair to the Dalek

Controller

Control of movement
One wheelchair has the full controller still attached. Paul may have another.
Controller is a Dynamic DK-PMA01 Shark Wheelchair Controller
https://www.dynamiccontrols.com/sites/default/files/2018-05/SHARK%20PMA_PMB_PMC%20Installation%20Manual%20Iss%207.pdf
Dynamic DK-PMA01 Shark Wheelchair Controller Diagram
Does the controller work?
It does. Drives the motors on the existing older wheel chair. However, as you can see from the diagram above from the manual the brake circuit on the controller is 24V, 24V motors and 24V brakes. The newer wheelchair has 24V motors and 12V brakes.

The Body

The Head

The head looks pretty good but is missing some elements and has some design issues:

Dalek Head Assembly
The "Hat"
Dalek Hat Top View
Dalek Hat Front View
Dalek Hat Side View
Dalek Hat Eyestalk Detail
Dalek Hat Light Detail
Dalek Hat Underside View
The Hat is of approximately the right dimensions and form.
It has suffered some damage in the past. It houses:
The head rotation mechanism
Fairly rudimentary bolt as a pivot. Needs work
The Head rotation "stick"
There is a mount for this to allow the operator to turn the head but the stick itself has snapped off. Needs either mechanising or making more solidly in metal for hand operation
The Eye stalk mechanism
Very basic bolt pivot with a string to pull and a return spring, which is missing.
The Antennae Lights
Rough holes in about the right places. Very poor light setup, a pair of indicator lenses may not be the right design. Needs major reworking (See illumination below)
Needs work to repair damage
Construction is fibreglass for the hat and plywood for the internal structure.
The Head body
Dalek Head Inside Top
Well built but of the 3 rings which should go round the head the bottom one is missing.
Dalek Head Side View Showing Missing Lower Ring
On of the 2 remaining 2 rings has been knocked and dislodged.
The remaining rings are showing signs of damage.
According to the Dalek Project guides we are missing vertical strips on the outside of the mesh but the inside of the rings. Each strip consists of 3 dowels bonded together.
The Head body has a front panel with mesh with no backing so that the operator can see out.
Dalek Head Drivers View
Along with the hat some work is required for the rotation mechanism to get it working smoothly.
Dalek Head Inside View From Below

The Mid-section

The Mid-section is very substantial and well made but seems to be missing a lot of detail.

Dalek Mid-section
Dalek Mid-section Side View
Dalek Mid-section Front View
Dalek Mid-section Underside View
Construction is plywood and fibreglass.
The Arm ports have the correct size orifices and are chamfered on the inside to allow installation of the arm sphere joints.
The arm ports have internal studding for a clamping mechanism for the arm spheres.
External Structures missing
From reading the Dalek Project build guides the mid-section is missing some detail. Exactly how much depends on which Dalek version you want to replicate.
Decide on which version we are replicating and make the relevant structure.
Sort out arm mechanisms / structure for pivot spheres.
Procure suitable spheres.

The Skirt

The Skirt is pretty well built.

Dalek Skirt
Construction is plywood and fibreglass. The forward section of the skirt itself is fibreglass. The rear thin ply possibly with fibreglass over the top.
The internal structure and seat is pretty solid and well constructed.
The bottom edge of the skirt flange / base is just a single thickness of ply. Again depending on which Dalek Mark we go for this would change thickness.
Wheel Chair installation / integration. Need a 3D model of the base and a rough model of the wheel chair structure to be able to see how the two could be mated together.
Initial CAD Model using measurements from our Dalek to start on trying to find out if we can fit the Wheelchair to it. Modelled with the skirt panels shown.
Initial CAD Model using measurements from our Dalek to start on trying to find out if we can fit the Wheelchair to it. Modelled with the skirt panels hidden showing the inner frame structure.
Missing domes need addressing.
Dome attachment isnt great and may not be as the Dalek Project guides suggest they should be mounted.

CAD Modelling

Weapons, limbs and stalks

Derek is missing all his suckers and stick out bits. Replacements need fashioning and installing.

Orifices
What size orifices does Derek have for installing limbs in to?
Correctly sized to accept ~100mm (4") spheres
Eye Stalk
What does Derek have for an eyestalk?
Nothing... but the pivot assembly is in place although it is rather rudimentary
What is there what is missing?
Have the pivot, it isn't the "official" size but it exists.
Pivot has really poor mechanical mounting for eye stalk.
Need stalk tube, acrylic rings, acrylic tube, Eyeball, iris/aperture, camera, LED
The "Gun"
Entirely missing. Need to decide on preferred Dalek version for defining correct gun design
The "Plunger"
Entirely missing. Need to decide on preferred Dalek version for defining correct plunger design

Cosmetics

Externally the finish is pretty good but some of the body domes are missing and need replacements making. Ideal candidate for a vacuum former

check over externals and compile a list of tasks
Domes are approx 103mm dia and 45mm tall
Correct number of domes are used
In all missing 5 domes on the skirt
2 domes are not attached but we have them
we have one dome base which has fallen off
Filling and painting
There are quite a few areas which are damaged and need work to repair but the paint looks to be really high quality.
Final Finishing can be addressed once all the mechanical issues are addressed.

Electronics

External lighting / illumination

Head lights
Type and Style appropriate for design
Weapon Lights
Does the weapon illuminate?
Eye Stalk illumination
Does it have lights?
Other Lighting
Are there other illumination effects
Skirt illumination
Head illumination

Sound effects for Dalek Voice modulation and weapon

Dalek Voice
Ring Modular Circuit
Best way to achieve this?
Make a Ring Modulator?
Use a PI?
Use an Arduino?
Buy the Project Dalek Forum Mk6 System, ~£100 but does everything.
Weapon Sounds
some kind of Pi or Arduino Sample player?
Remote Control
Be able to drive the Dalek remotely?
Eye Stalk video camera
Set up a remote viewing video camera?

Ring Modulator

Found this site

which links to this

which in turn links to Github page

and this PCB

So I have ordered the PCB (you get 3 for $23!) Will see what develops.

Parts List
MCP3204 RS Stock No.: 379-2465
MCP4921 RS Stock No.: 738-6027
Audio Jack
1K resistor
1.5K resistor
330 ohm resistor
0.1 uF capacitor
10 uF electrolytic capacitor (2mm spacing)
LED T1-3/4 (5mm) RED
36-pin header
10K Trimpot

Useful Links and Resources

Project Dalek

Dalek Voice Modulator