Latest (2017.09.24):

Work on the code for the chip on the drive board - preset speeds for the 4 motors and steering motor. There will be 7 speeds forward, 7 reverse, and stationary. The steering motor will follow the direction the controller is pointing in.

Controller circuits:

Compass, Keypad and potentiometer, LCD for simplifying design, Rotation indication, Encoder for mode switch and GPS power switch, Speech/sound effects module, TransceiverGPS module.

Carriage circuits:

Compass, LCD for diagnostics, Receiver, Steering control, Drive control, Speech/sound effects module, GPS module. 


The Controller so far: 





The Leds are only lit one at a time, camera shutter speed is too slow in this photo: 



Underneath of LEDs/keypad/speed control board, in the making: 



Carriage so far. MDF used extensively like in the Controller:



Battery charger before holes drilled in top and before LCD fitted for current and voltage of each: 



Test electronics for the Controller unit, from left to right - transceiver controller (mostly wired), display and controller, basic switch encoder, compass module, gyroscope/accelerometer/thermometer module (not to be used now), and controller chip. The controller chip has a USB peripheral which will be wired in case of the desire for PC operation. The transceiver is just that, and could also feed back to a PC, as the transceiver for the carriage unit is the same type. 


Labs used for the audio (on right) and other circuit experimentation:



Project base from August:



Rough rig for measuring speed of the motors, each has 3 tests and the driving circuit can be tuned for consistency (invalid data shown, not in use yet):




Stages so far:


- Audio working, code for drive control chip and main control chip. 

- Soldered the rest of the components to the remaining boards and tested. Because I'm about to begin work on the motors and speeds, I made the battery charger also, 4-channel. It will have an LCD to monitor voltage and current of each, but after the main construction is complete. Fitted stereo socket that will allow the carriage to be used as a general purpose audio amplifier.

- Made the power amps board and some of the control chip board, both for the carriage. Work on pwm chip code. Readied the chassis for the remaining boards. Work on the digital audio board, which was a prototype.

- Remade four of the carriage circuit board etchings after using different printer settings on the acetate.

- Fitted the speakers to the carriage.

- PCB making for the carriage, one is already made.

- Power switch wiring and speakers wiring.

- CAD and code for various parts of the carriage circuitry. Readying of a cgsng prototype digital audio board, which will be replaced later possibly. This uses parallel control, as desired here. Fitted the batteries to the chassis. Created 12 audio files the Rover will play, selected by keypad keys on the controller unit.

- Work on I2C send and receive. Carriage chassis now accommodates the 4 batteries underneath and the speakers when they arrive. It looks like the design won't be ready this month.

- Fitted top hardware except the audio boards, and speaker enclosures which are yet to be made. Speakers will have a covering plate as a temporary measure.

- More hardware work, mode switch firmware, work on digital audio board. This will be fitted later as the comms between the input there and the audio chip needs more connections.

- As below.

- Work on the speed control and direction, hardware for. Work on the transceiver board for the Controller. It uses a transceiver rather than a transmitter because there is the option for 2-way communications.

- Work on Audio amplifiers and SD card stage, and on Transceiver.

- Design and hardware for audio. Transceiver board designed but radio module changed, so will be done again.

-Working on the audio for the controller and upper mechanical components of it also.

- Finished underneath of Carriage. Improved Controller compass mounting.

- Assembled the Rotation indication / GPS board and the mode switch / GPS power board. Extracted the geographical data from the GPS that is needed. Switch is inverted, but easily fixed. Also painted the backs of the large switch boards, for best effect.

- Work on the wheel supports and gears, etched more circuit boards (only two left to do for the controller now).

- CAD for Rotation and GPS board.

- Speeded up the communications with the components to as fast as possible without error. More work on wheels.

- Keypad/Channel switch/Movement (forward-reverse)/Leds board finished and programmed, including sequences to show status. Begun fitting the wheels to the carriage.

- Part way through construction and testing of board for keypad, leds and channel switch. Other hardware items.

- Made Controller control board and fitted, added the compass. Fitted the Controller hardware parts made so far.

- Hardware work, assembled LCD unit.

- More CAD and programming, some hardware assembly.

- Made power/signals distribution board for the controller, made LCD board and ready to solder. CAD for making the controller's controller module.

- Fitted bearings to wheels, driving gear and them all to chassis.

- Begun painting the externals of the controller. More CAD work and externals made. Bought the carriage bearings again, because Royal Mail have lost the first ones.

- CAD work and chose a 2 line display rather than 4. Potentiometer to be used instead of gyroscope/accelerometer, having chosen a better idea for the motion control. Also, as standard the Controller will be able to address up to 4 Rovers or one could use those channels for playing extra recorded sounds, or up to 4 Rovers could play the same sounds at the same time....!

-Hardware work.

- Made a circuit for counting pulses from the wheels turning, because the speed of each motor is different.

- Work on sensor data using diagnostics display.

- Assembled wheels/servos.

- Waiting for parts, begun making the controller case.

- Most of the transmitter circuit made. Two emails sent to the ebay seller who is supposed to be sending the servos.

- Made the 5 gears and chassis.

- Switch circuit and LCD status/diagnostic circuit for the controller/transmitter;

- Begun making the gears which each servo and wheel are attached to, driven by a fifth, which is driven by the same type of servo also;

- More work on controller experimental circuitry;

- Some items bought for the carriage: 4x wheels, 4x 15.4kg/cm servos, flat bearings, electronics


Also - workshop improvements at times and setting up of a work area in a spare room.





Gears best 5 out of 6 made, but it wasn't be done in TV cookery program style, just a simple choice without the condemning that they do. Drive wheels are 50mm diameter, and at 10mm wide will allow a speed of about 6 inches per second and easy turning.