This is an own version of the D-O droid, this droid does not really exist in the saga. However, I have thought it convenient to do so for various reasons.
I think that a small droid of these characteristics can offer a lot of fun, not only because of its peculiar movement, or because the dark side must also have powerful droids … If not because the side weapon can be easily changed. I plan to make more types of weapons to be able to exchange them.
The inner part of the droid has hardly changed, only a couple of pieces have been modified and a servo has been removed. The central drive part of the weapon has been replaced and now has a coupling with 8 powerful neodymium magnets.
The weapon has a 10-pin connector that allows you to change the weapon with ease. This connector follows the same wiring standard as there is on the internal board, in this way all the features are available to be able to connect whatever is necessary.
Remembering that the board in this connector allows to have:
- One analog input.
- Three Led outputs (no pull-down resistance is necessary).
- Two PWM outputs for servo.
- 6v power supply for servos.
- 5v supply for logic.
Making the weapon …
To create the cannon I have decided to use aluminum tubes that better transmit the light beam from the led that produces the shooting effect. All the gold tubes seen in the picture below are gold aluminum tubes.
In addition to the fact that the finish with gold paint is better received in this type of material, I think that printing would not have been the same.
Inside there is a modified servo that is responsible for the rotation of the barrel (I’ll talk about this later). It is modified to easily reach many more revolutions, this makes it more faithful to how it should be in reality.
At the top there is like a simulated set of telemetry, a digital remote control that houses a 5mm yellow led. On the back I have decided to mount an antenna (it is a wifi antenna easy to find online) and its base to fix it.
The barrel is made up of 6 aluminum tubes 6mm in diameter by 60mm in length, mounted on three printed rings. They are glued so they do not move. When assembling you have to note that: Of the three rings printed, there are two the same and one different.
In the image below we can see the measurements:
The tubes of the weapon including those of the telemetry are:
- 6 Ø6mm x 60mm
- 1 of Ø8mm x 25mm
- 1 of Ø6mm x 16mm
The lid is attached with 4 neodymium magnets 6mm x 3mm thick. On the back there are 8 identical magnets to attach the weapon to the body.
This is the one-line diagram of what is inside the weapon
I have used a MG90S servo to rotate the barrel, but … A servo as it comes from origin does not work … There are two modifications to make: One so that it becomes a continuously rotating servo and another to get the rotation speed is much faster.
How do we do this? … First we completely disassemble the servo and cut the axis of the big wheel (the axis of the servo) so that it does not operate on the potentiometer that regulates the position.
Then the sprocket of that same axis is joined with the one that originally goes underneath. I have used nural-11 to make this union.
When making this modification we eliminate the pinion “A” of the servo, taking one step away from the reduction, in this way the axis of the servo is much faster.
The next thing we must do is connect the servo to the droid to adjust the “no movement”, that is, the servo, as it is, will not have a position criterion since we have cut the axis that served to control it. By connecting it to the droid and feeding it, the motor will begin to spin without further ado …
So what we have to do now is turn the potentiometer manually with a watchmaker’s screwdriver until the motor stops. We do this by inserting the screwdriver through the hole in the main shaft (the one we have cut).
Finally it is assembled without mounting the pinion “A” and ready … We have the servo modified and ready to use it in the weapon.