R2-D2 Current Electronics

May 4 2015

In preparation for my second R2 I started to put together the electronics for the new droid. My current R2 and R5 I can remove the electronics from the body to work on and trouble shoot if needed. As an added bonus I can switch the electronics between my droids.

I figured I would follow the same technique so that while I work on my se3codn R2 I can use the new electronic in my current R2. My current R2 has developed a buzz in the motors. Part of this is due to the motors and part due to the speed controllers. I have added capacitors to the motors but that did not help. Adding capacitors to the motors are supposed to reduce the buzz sound.

So the following is the current electronics in my R2

Transmitter

Description

This is what is used to transmit the signals to your droid to get it to do what you want. There are currently different systems that people use. RC radio, Hacked PS2 Controller, Android app etc.

The simplest solution is using a RC radio that is used for RC planes and cars. Older systems used 72MHz and 75MHz. The older systems were more susceptible to interference. The newer systems used 2 channels on the 2.4GHz spectrum to make sure you maintain the signal to your receiver. Quite a few builders used the Spektrum DX6 model but the Orange transmitters have been getting fairly good reviews and the prices are lower.

RC Radios come in a Mode 1 and a Mode 2. I prefer Mode 2 which means the throttle Y axis in on the left joystick. I and a lot of droid builders use the right joystick to drive their Droid and the X-axis on the left joystick for the dome rotation.

Although you need only 3 channels to drive and control the dome the other 3 channels can be used to control other functions in your droid.

The 10 memory function allows me to program 10 different robots with this radio. It will also allow me to have different characteristics for the same droid. If I am in a crowd I would like to have fine control of my droid so I do not hit or run over people. In larger open areas I would like the droid to have a higher top speed.

The hacked PS2 Controller uses an Arduino to interpret the signals from the PS2 controller to control your droid. A fellow builder has done all the research and programming to get this system working fairly well. The benefit of this system is that the controller is smaller then an RC controller so it is easier to hide. The programming of the buttons givers a convenient way control the sounds.

Others are also looking into using their smart hone to control the driving of their droid. I have not been following it so I can not comment any more on that.

Currently I prefer the RC radio as it is a proven system, is simple to set up and has a nice range.

Model used:

OrangeRx T-SIX 2.4GHz DSM2 Comp. 6CH Programmable Transmitter w/10 Model Memory (Mode 2) - $60

Web Site: http://www.hobbyking.com

Receiver

Description

This is what receives the signals from your transmitter and controls other function in your droid

The receiver I have schosen allows me to use all 6 channels of my transmitter. The low price means I can buy several of these and put them in different robots and use the same radio to control them.

 

OrangeRx R615X DSM2/DSMX Compatible 6Ch 2.4GHz Receiver w/CPPM $12

Web Site: http://www.hobbyking.com

Speed Controller

Description

The speed controller with what takes the signal from the receiver and sends the power to the motors. The receiver can not control the voltage and current needed for the motor so that is why the speed controller is needed.

There are a wide range of speed controllers depending on the motors and voltages you are using. The motors a lot of builders are using is the 100W scooter motors at 24VDC. They are plentiful and relatively inexpensive for the power output you get. The speed controller I have am using can control 2 channels at 6-30VDC at 25A each. The scooter motors will use a lot less than the 25A so this speed controller is a good choice.

This speed controllers also has a bunch of dip switches to allow you to change some characteristics of the speed controller. My transmitter radio has channel mixing but some of the less expensive and older models do not have it. Although I do not use channel mixing some people use it for driving their droids

 

 

Sabertooth 2X25 dual 25A motor driver $125

Web Site: http://www.dimensionengineering.com/products/sabertooth2x25

12CH RF Remote

Description

Before the PS2 Controller hack and the various Bluetooth products the method most builders used to control sound on their droid was using the 12CH RF remote and an MP3/Wav Player.

With the correct MP3/Wav player you can chose specific sounds to play. This can add so much life to your droid.

There are different remotes but I prefer the RF (Radio Frequency) remote since it is inexpensive. Although there are cheaper Infrared remotes those type of remotes require that the transmitter and receiver have a line of sight. This means if there are any obstacles between the transmitter and receiver the remote will not work.

The radio frequency remote means the receiver can be hidden in your droid and that it will work even if there are people between you and the receiver.

Some people will have a second unit and have that control other functions of their droid. It is an inexpensive and fairly reliable method to add functions to your droid.

 

 

Sound

Description

This item allows for individual accessing of an mp3 or wav file on command. The unit I have can be triggered by the 12CH RF remote receiver directly. Other units may require an interface Picaxe/arduino etc to control the sound player. The below item does not need this interface

This system requires you to put mp3 files (specifically named) onto an micro SD card that is plugged into the sound card. The benefit of this is that you can quickly change the sound files being played as needed.

https://www.sparkfun.com/products/11029

$50

Sparkfun produces an Mp3 and a wav player. The choice is what ever file format you want.

 

 

Items I have not gotten yet

Dome controller

Lights