Home > Dalek Project > Joystick Construction
Modified:22:22, 22 October 2013
DALEK PAGES
JOYSTICK FOR MANUAL CONTROL

The joysticks were intended for manual control while sitting inside the Dalek. Two joystickas with x and y axis proportional control was required. To buy these is very expensive so I took a couple of attempts to make them myself. Version 1 proved not robust enough so the second version was much tougher made from 8mm clear acrylic.

  • LEFT JOYSTICK: y-axis = left motor forward/back, x-axis = Eye stalk up/down
  • RIGHT JOYSTICK: y-axis = right motor forward/back, x-axis = Head rotation clockwise/anti-clockwise
Joystick Design Version 1
The design of the first version was drawn on a Micrografx Draw package from 1992! But it still enabled the working of the joystick to be worked out.
The principle was to develop a mechanism that would centre the joystick when released, but give up to 25 degrees from centre in either direction. THis was connected to a potentiometer to give a proportional reading. There were problems in that getting springs strong enough to overcome the leverage produced by the length of the lever.
These are the paddles that make the lever revert to centre position. These were cut and shaped from hardwood, oak I think. The lever was made from dowel with a chisel handle at the end. The paddles were attached to spring to pull them up thus levelling the yoke. The final pair with potentiometers attached. They were tested and worked well enough but just seemed too flimsy. So to version 2..
Joystick Design Version 2 - y-axis
The design was drawn out on good oold Micrografx Draw (the last time I ever used it I think). Right is a 1st or 3rd (can never remember) angle projection of the design. It has the y-axis assembly cradled inside the case on pivots to provide x-axis control.

All parts were manufactured from raw material except the roller catches which were from B&Q

The first part was the yoke. This was made from nylon rod we had turned on the lathe to produce pivots. Nylon is kinda self lubricating so would simplify construction. The completed yoke with a flat side sanded using a sanding belt. This is where the threaded 8mm metal rod will be inserted The case was laser cut from 8mm clear acrylic. The picture above shows 2 y-axis assemblies.
The case was assembled by drilling 2.5mm holes and using M2.5 bolts. All bolts were countersunk. The yoke being tapped ready for the bar which will act as the main lever section. Lever in place with locking nut and washer to prevent it from coming loose after repeated use.

Roller latches were used as the spring device to centre the joystick. These were placed either side of the lever near the yoke. The roller springs are quite stiff but close to the base they provided the perfect amount of resitance. And cheap as chips!

The addition of the potentiometer, without the mount yet in place. The lever provides about 30 degrees of movement and this in turn is transferred to the potentiometer. The roller latches in place. The slotted mounts enabled adjustment. This section is now mounted inside another acrylic frame on pivots to provide an x-axis control.
Joystick Design Version 2 - x-axis pivot pins
The entire y-axis assembly needs to pivot inside a case so aluminium pins were turned on the lathe. These were threaded on one end and screwed into a tapped hole in the acrylic assembly.

The other end was turned to a diameter of 10 mm. This will pivot inside a 10mm hole on the outer case.

One pivot pin is blank and just provides support. The other end needs a hole for the potentiometer shaft. 

While I was at it I decided to tap a grub screw fixing into the body to ensure the shaft didn't slip with sudden movements.

Joystick Version 2 -Assembly
Fixing the outer case of the joysticks together using M2.5 bolts again. All ends and cuts were sanded and polished. Making large polystyrene washers for mounting the y-axis section.
Two more roller catches back to back held the assembly central thus resulting in an analogue proptional 2 axis joystick. The entire assembly was very robust.

And being made from 8mm clear acrylic, yup I put multicolour LEDs in theacrylic to light it the same coour as the base. Result = moodlight joysticks!!

Below the LEDs are wired to connector block connect to the Base LED controller.

The potentiometers have twisted blue and violet wire pairs to the controllers.

Written and Constructed by Phil Townshend 2009
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