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In an attempt to minimize complexity and cost, I have built a series of  modular circuit boards. Vero board is used exclusively. Circuits are drawn
on the computer using DesignSpark PCB software, which is freeware.
The output "Netlist" from DesignSpark is then imported into VeeCad,
which can be either freeware or a paid version. The latter  is much better.
Drawings are printed out and glued onto the top side of the Vero board. Track cutout positions can be located easily with a pin. Top side wire links complete the connections. Individual Picaxe microprocessors are used throughout the design using a small versatile Veroboard.
Diagram Of Layout
Machine Construction Home Page
Brushless DC Motor Theory
Details & Photos Smartdrive Motor
Four 12volt car batteries are used for the power supply. Three are connected in series for 36vdc to the motor electro magnets, also a 6vdc  battery is fitted for 18volts to drive  the mosfet gates. An electrically  isolated auxiliary 12 volt battery supplies the regulated 5v power for the microprocessors and Hall Effect sensors. Fuses are placed at all battery connection terminals, and also on most circuit boards.
Hall Effect Sensor Decoding
Coils And Magnets
Power first goes to circuit Board1, where a light duty switch immediately activates a car type relay for the high current 36v motor supply. Also included is a delayed turn on of 3 secs, using a Picaxe 08M. The delay is to protect the digital ampmeter from the initial current surge to charge the capacitors. A small DPDT relay controls both the 18v Mosfet supply and the 12v isolated supply for the micros and Hall Effect Sensors.
Various Pieces Of Test Equiptment
Coasting Relay Setup
A circuit board with OpAmps to convert the Hall Sensor analog data to digital is used. This board ELIMINATES the need
for computer programming for the motor
drive. Multiple Picaxe micros are used to
control individual functions, so the programming can be kept simple.
Hall Effect position sensors are mounted
on the motor frame. To get more accurate switching, and to adjust for minimal power use, 2 sets of 3 Hall Sensors are used. These sets are adjustable relative to the frame/coil positions, and also
relative to each other.
Guide Wheel Details
Picaxe 18M2 PCB
Possible Lateral Drive Methods
Electro Magnetic Rotor Stabilization
A board with AND/NAND gates enables the OpAmp board's  6 motor drive outputs to be combined with a micro's Pulse Width Modulation output to 3 gates for  High Side Mosfet voltage/speed control. The PWM of the motor is applied only to the High Side Mosfets. Each time the HS Mosfet switches off the Low Side remains on, thereby enabling the IR2103 Gate Driver to recharge its bootstrap capacitor when the floating part of the circuit goes to ground. A Picaxe Micro is used for the PWM, but a 555 timer could do the job. 
This section is 3 identical boards each containing 1 high side mosfet and 1 low side mosfet to supply the power for motor drive. Mosfet drivers are fitted to provide voltage
boost for the gate drive. Also fitted are optocouplers to protect the Picaxe micros, Hall Sensors and logic gates from any motor voltage spikes.