Red Dragon Motor Drivers

 

The Red Dragon 1 can be used as a stand alone motor driver without either the Picaxe chip or the RF remote board. 2 L293D chips can control 4 motors (to about 1 amp limit), forward and reverse with 8 digital control inputs. Put positive voltage on motor #1 forward connection and the motor goes forward. Please note the output voltage to the motor will be about 3/4 the supply voltage. So an 8 volt supply would be about 6 volts at the motor when it is activated. This kit will require soldering, sample wiring diagrams are included.

• 2 L293D chips
• 2 chip sockets
• A quick reference guide
• Red Dragon 1 circuit board.

The Red Dragon 1 board is a PICAXE 18M2 PC programmable microcomputer with onboard memory for 1800 lines of code. 2 motor driver chips you to have 4 motors under program control forward and reverse. The board has contacts designed to solder on inexpensive 4 & 6 channel RF remote control receiver boards. You then use the small remotes press a button they will be detected on PICAXE pins and can be used live under program control. I include the full specs of the board so you can experiment beon the motor driver and build a full system if you wish.

This kit only includes the motor driver parts of the board and a guide on how to tap into just the motor driver outputs and input signal lines. You do not need the PICAXE chip or a remote receiver board to use just motor driver. Please note that control inputs for motors #1 and #2 are at the PICAXE chip socket pins. Control inputs for the motors #3 and #4 are the 4 pin header connections along the edge of the board. If you only wish to control one motor you can omit one of the L293D chips.

PICAXE FireTruck. fond memories

Ran out of the Fire Trucks to mod into robots.  Until I get a new source for the basic wired Fire Truck at good cost we have created my last one.  This was one of first Picaxe Robots and one of my favorites. The drive and steering motors was about as close to RC quality that would find in a toy like this. It had a small sound and light board that I was able to activate under program control.   I started out with 8 pin Picaxes and advanced over the years to include 18MC wire remote control input. The first ones I hardwired the programming serial port cable and wrapped it around the hose racks on the rear of the truck. The nice thing about having a separate circuit running the lights and sounds is that you could activate the circuit and then you could keep running the main program.  We call that poor man multitasking. Check out that 5 point turn subroutine.

I had just a few of this other model Fire Truck, it had even wider turning ratio.  I had to program in 10 point turns to do a 360.

I enjoyed writing programs for a real truck with lots of steps to do a turn.  The steering only angled few degrees and I only had a few 100 lines of code for these dinosaurs. I had a small bumper switch that would start the program to do a slow 360.  It would randomly drive around and backup and turn around if it hit anything.  We upgraded to a detachable programming serial cable.

I will sure miss writing software for that old bus.

RED Dragon 2 20M2 / 18M2 Picaxe

This kit includes the bare PC board only and documents only. Your can add a PICAXE 18M2 or 20M2 Pic Microcomputer and add either a 4, 6, or 8 channel RF remote control system for inputs. Plus you can add up to 2 L293D chips for motor drivers. So you can control up to 4 motors reverse and forward from the picaxe. Please note the output voltage to the motor will be about 3/4 the motor supply voltage. So an 8 volt motor supply would be about 6 volts at the motor when it is activated. The PICAXE is easy to program with a standard serial cable and a windows computer with a serial port. I will include the software and PICAXE programming manuals on a CD. This kit will require soldering, sample wiring diagrams are included. 

Red Dragon 2 circuit board.
4,6,8 Channel RF Receiver.
4,6,8 Channel remote with battery.
PICAXE 18M2 or 20M2 chip.
2 L293D chips
IC sockets
PICAXE programming resistors.
Serial Cable Connector
5 Foot Serial Cable.
PICAXE Software & Manual on CD.
Red Dragon user guide.

The Red Dragon 2 board is a PICAXE 18M2 or 20M2 PIC programmable microcomputer with onboard memory for 1800 lines of code. 2 motor driver chips you to have 4 motors under program control forward and reverse. The board has contacts designed to solder on inexpensive 4, 6, or 8 channel RF remote control receiver boards. The 8 channel remote can only be used with the 20M2 Picaxe. You can press a button on the small remote and it will be detected on PICAXE pins and can be acted upon under program control. I include the full specs of the board so you can experiment beon the motor driver and build a full system if you wish.

This kit only includes the board and the guide on CD. You do not need the PICAXE chip or a remote receiver board to use just motor driver. Please note that control inputs for motors #1 and #2 are at the PICAXE chip socket pins. Control inputs for the motors #3 and #4 are the 4 pin header connections along the edge of the board. If you only wish to control one motor you can omit one of the L293D chips.

RED DRAGON1 Intro

After many years of research and testing I have finally started to mass produce my own design of a Universal robot controller Circuit Board.  My goal was to produce a small computer that could directly drive motors and that had low cost long range remote control and that could provide real-time inputs to the computer.   A cheap computer (couple of dollars), 4 cheap digital 1amp motor drivers (couple of dollars) and a cheap long range remote control system (couple of dollars).  I just wanted a cheap circuit I could drop in any toy with motors and remotely operate the motors with some computer control in there, to operate sequences of movements or complex motor actions (1000 lines of code that can do math maybe?) from a simple press on a remote button.  Oh and want to buy the cheapest chips and remotes I could buy on eBay.  This is the Red Dragon 1 with the a PICAXE 18M2 multitasking microcomputer (it can have 4 programs running at the same time but they are actually only executed one at time, just very fast).


 So its not just a remote controlled motor driver, but motor drivers with a computer interface. The PICAXE 18M2 microcomputer lets you run about 1800 lines of code.  I intended to use the RED DRAGON as a cheap universal remote control for toy vehicles and robots.  Just take a remote control toy that has lost its remote, cut out the radio circuit, solder the RED DRAGON to the motor wires there you go.  You made a long range RC Robot with a computer interface.  The RED DRAGON 1 is a full function PICAXE 18M2 breakout board.  The serial port programming resistors are on board so only a serial cable is required to program the PICAXE.  8 of the PICAXE output pins are connected to 2 on L293D chips that can directly power 1 amp motors using program control.  Here is the basic board layout.

You can only use either the 4 channel RF circuit or the 6 channel but not both at the same time (they use some of the same inputs so it would not work).  You can also not use the remote boards and just wire inputs and outputs to those 2 rows of pin headers.   Here is the port addresses on the pin header.

 

There are also spare POS + and GND ports on the pin header that can be used.  The power is the same 6+volt POS PICAXE & RADIO bus.  The - GND is the connected to the 2 other GND connectors on the board.  Please note the GND for PICAXE and Radio power is tied to the GND on the motor supply connector.  These GNDs must stay connected for the proper function of the Motor Driver circuit.  It has been tested that the POS + for the PICAXE and the POS + for the Motor Supply can be the same source if the motors do not pull too much current.  Otherwise high current on the motors can cause the PICAXE to reboot randomly.