R2-D2 ELECTRONICS -
AND THE BRAINS BEHIND THE DROID
My
plan is to be able to control R2 completely by RC Radio
Control and eventually by Computer (PC) "Automonous" control.
I've about collected everything I'm
going to need as far as hardware. Now to find a way to pack
all this electronics into the limited are inside R2's frame.
Also, I will have to cram in the largest Lead Acid batteries
that you can fit into the thing so he will run as long as possible.
This is the hardest part besides trying to collect and build
the parts
needed for an R2-D2 project!
PCB's
The following is a list of Printed Circuit Boards (PCB's) and other
electronics and hardware that will be installed into R2.
- Main Drive
Motor Controller
- RoboteQ AX3500. This controller is very
programmable and computer or RC controllable. It will also
switch between RC and PC control on the fly. 2 channels of the RC
receiver are used on this controller for single stick control for
driving R2. Information on RoboteQ motor controllers can be found
at RoboteQ Homepage.
- PCB1 Motor
Controller and Power Regulator Board - Mark Hamesters PCB1
performs many functions, including supplying multiple regulated voltage
sources from a +24VDC input, 4 PWM controlled FET motor outputs with
end-of-travel limit switch inputs and other functions. Currently used for Dome Motor control from the RC radio.
- PCB2 R2
Controller - Mark Hamesters PCB2 had multiple outputs controlled by a
PC. Included is a LCD display screen.
- LEAF Project
Robot Controller - Not sure yet if I'm going to use this.
Check out the Leaf Robot Project Home Page web site for more information.
COMPUTER/PC SYSTEM
Components were selected for small size, performance and minimum power
requirements. This particular model mother board/PC includes 4 USB ports, PC Card Slot, and a Compact
Flash Card slot.
The PC will be dual-boot with Windows and Linux. I'm writing
software (and others) for the PC to control sounds, 2-3-2, monitor
battery voltage and a bunch of other functions. Eventually will
have a semi-autonomous mode where R2 will run around pretty much on his
own in certain environments.
- Main Board -
A Mini-ITX form factor mother board with a VIA C7 processor running at
1.5 Ghz
- RAM - 1Gb
- 2Gb IDE Flash Module "Drive"
- Hard Drive - 120Gb 2.5 inch (notebook)
- DVD/CD Drive - Laptop style slim-line type drive. To be mounted behind Large Data Port (LDP).
- 60 watt "Pico" Power Supply, runs from 6VDC to 28VDC input (!)
08/24/06 : Mini ITX PC finally here!
DOME SLIP RING
I'm
testing out the slip ring sent to me by Bruce Maley "High Tech Redneck". I had problems with the original
plastic mounting ring (cracked, crazed) maybe due to using Lock-tite on the
mounting screws? Anyway, I had to grind off the old plastic mounting flange
and glue on/install a metal one. I like it better anyway as it covers up
the hole cut in ring 1 as I needed to pass through the DB-25
connectors.
The Slip Ring harness has a male DB-25 on one end that runs to R2's
body, and a female DB-25
connector to attach to the connector mounted inside the dome ring.
The wires that came with the slip ring were just long enough to
reach the Dome Connector and no trimming of the original wires/harness
was required.
The slip ring is made in China and has 24 contacts, capable of 2 amps
per contact. Even with this amount of contacts, will wind up
using quite a few for ground returns due to current draw within the
dome assembly.
10/26/07 : UPDATE :
The slip ring has performed flawlessly since installation prior
to CIV. I have had no problems with signals, DC power, etc. using
this part. I also created a worksheet using Excel to map out the
signals/connections through the slip ring. It can be found here:
Current Slip Ring Assignment Worksheet (Excel)
04/21/06 : Slip Ring Harness assembly. Replacement aluminum mounting flange shown.
04/21/06 : Slip Ring mounting hole. Cutout is to pass DB-25 connectors.
04/21/06 : Slip Ring ready to be mounted on Ring 1.
04/21/06 : Slip Ring installed with 3 ea. 10-32 UNC screws and split washers.
04/21/06 : Bracket for DB-25 female connector that is mounted on dome ring. I used an backplate
for a PC to trace out the DB-25 outline, then the good old Dremel came out with some filing.
04/21/06 : Bracket installed inside dome for Slip Ring connections.
HP LIGHT SOURCE
04/11/06 : Components of my HP light source. I used a 3 watt Luxeon LED conversion LED
for a 4 cell Mag-lite flashlight. Then I took apart an old Mag-lite and ground down the
reflector to just fit into the hole in the HP. I then took brass tubing and built up the casing that
surrounds the LED assembly. This will then be glued into the rear of the reflector assembly.
The Luxeon's need a heat-sink and the brass tubing should do the job.
04/11/06 : Can you say BRIGHT! This is a side shot of the reflector and Luxeon LED assembly.
I'm going to put in a circuit to control the brightness as you sure do not want a kid to
look directly into this thing! LED runs off a 6V power source. This picture is just a shot of the
reflector assembly. I may put a light blue colored filter to simulate the color of Leia on ANH even
though the "beam" from R2 was white...
04/11/06 : Here it is finalized. HP ready to go back into the dome. Will be switched on/off with
a channel "slider" on the R/C radio feed through the PCB2 output ports.
---
08/26/06 : R2 at the Southern Builders meeting.
PCB1, PCB2, AX3500 powered up and operational :)
Rear view of PCB's and current revision of control panel. Control panel
will be accessible through rear right door. On the bottom of the panel
there are two sets of 30 amp aircraft style "pop out" circuit breakers for
the two set's of 24V batteries. The toggle switches on the top are for
PCB1/PCB2 power, AX3500 motor controller power, and PC power.
LAYING OUT AND MOUNTING ELECTRONICS MOUNTING PANELS
8/18/06 :
Laying out the AX3500 motor controller mounting plate.
8/18/06 : Mounting plate for AX3500 Motor Controller completed.
Three holes on the left are
for the nylon 3/4" cable clamps that will be used for hinges.
The holes on the left are through
holes which mounting screws fasten the panel to the right rear 3/4"
vertical rod. The vertical
rod was drilled and tapped to accept the mounting screws (6-32).
The oval hole is for cable
pass-through.
8/18/06 :
Mounting plate for AX3500 Motor Controller mounting attached to bottom
rear of
R2's frame. Shows hinges and retaining screws.
08/18/06 : PCB1 and AX3500 mounting plates. The screws on the
right of the panel are screwed
into the right vertical 3/4" rod. I can take those out and
the panels will hinge out to the left allowing
access to inside of R2 if needed.
---
PCB2 mounting. Located on rear of hinged PCB1 mounting plate.
I was originally going to use piano hinges, but decided that it
would be better to use the 3/4" nylon cable clamps due to possible
frame flex. Hinged panels were used for serviceability :)
Initial test mounting of rear control panel.
Main battery circuit breakers and other controls
will be mounted here to allow access by opening
one of R2's rear vertical doors.
---
08/06/06 : Trying a mock up using foam-core board
to simulated mounting the many PCB's that will be
in control of R2.
AX3500 MOTOR CONTROLLER TESTING
08/04/06 : The RoboteQ AX3500 board and kit
as received from the manufacturer.
Within an
hour of opening the controller box, I had
the AX3500 running one of the 100 watt scooter
motors using both my PC and my Futaba 9CAP
RC radio setup, sweet!
First Created: August 10th, 2006
Last updated: June 21st, 2007
Time: 1852 EST
