[Dr_C2]

Time to share a little playful project where I am experimenting with 2-part decoders. In this configuration the mainboard carries the diodes, microcontroller, strobe LED and, if required some lighting circuits. The MOSFET power control board is soldered directly onto the motor. There is a whole range of pros and cons with this type of configuration including future plug-and-play brushed versus brushless motor options. 

My main motivation for this project is to fit a high spec decoder into a slim F1 chassis. The decoder in the photo is equipped with 18A motor/brake MOSFETs. Perfect for 50k evo king motors on a heavily mag’ed drag strip setup :)




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[Dr_C2]

   

[MrFlippant]

Good to see you again! Now that's some innovation. :)

[Flux Capacitor]

Very nice!

[Dr_C2]

Thanks Mr F et al.,

Meanwhile some technical specifications:

1/ The dual MOSFET, which sits directing in front of the motor shaft is rated at 18 Amps for each of the n-channel and p-channel transistors.

2/ The bridge rectifier diodes (required for SSD mode) are rated at 10 Amps each giving a total current carrying capability of 20 Amps.

3/ There is an SSD compatible IR LED underneath and yes these cars drive very nicely on standard plastic track with borders IMO.

The two part design has been optimised for NSR motors in both F1 and saloon configurations. For example the design also fits the Z4 anglewinder chassis.

This is a very high drive current decoder.

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[Dr_C2]

So where next with this thread?

What I am thinking is to bring some technical ‘jigsaw puzzle’ pieces together in a fun way. 

So next I will share some images of the Z4 I mentioned above. These are NSR Z4’s which provide more opportunities for stacking of magnets - hopefully this will improve traction in comparison with the F1’s when accelerating hard.

Then, I will share the track-side speed measurement system which comprises two blade detectors with known spacing and an Atmega microcontroller as time keeper. This setup requires a precision oscillator alongside the microcontroller if its to perform as a true point-to-pointing racing precision chronograph.

From there we can look at finish line transit speeds for the F1 2022’s and BMW Z4’s with their standard 21k motors, going up in steps to the evo king 50k motors. Let’s see where we get to.

So that’s the plan. I hope it will be an interesting and informative exercise to share over this thread over the coming weeks and maybe months. This is, afterall, a hobby project so no firm deadlines ;)

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[Flux Capacitor]

So where next with this thread?

What I am thinking is to bring some technical ‘jigsaw puzzle’ pieces together in a fun way. 

So next I will share some images of the Z4 I mentioned above. These are NSR Z4’s which provide more opportunities for stacking of magnets - hopefully this will improve traction in comparison with the F1’s when accelerating hard.

Then, I will share the track-side speed measurement system which comprises two blade detectors with known spacing and an Atmega microcontroller as time keeper. This setup requires a precision oscillator alongside the microcontroller if its to perform as a true point-to-pointing racing precision chronograph.

From there we can look at finish line transit speeds for the F1 2022’s and BMW Z4’s with their standard 21k motors, going up in steps to the evo king 50k motors. Let’s see where we get to.

So that’s the plan. I hope it will be an interesting and informative exercise to share over this thread over the coming weeks and maybe months. This is, afterall, a hobby project so no firm deadlines ;)

c

How are the speed results displayed?

[Dr_C2]

Thanks Flux. I’m using four digit white LED displays (one per lane) with the format ‘88.88’ and with readout in m/s. They’re driven from the ATmega using a simple I2C bus. Also there is an option to data-log over USB for review later on.

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[Dr_C2]

A blue NSR Z4 in anglewinder configuration with the same type of solder-onto-the motor MOSFET power control board as shown earlier for the yellow F1 car. Wiring from left to right: motor PWM (white), brake PWM (blue), 0 Volts DC (Black) and +12 Volts DC (Red).

   

Next, on to the digital speed read-out.

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[Flux Capacitor]

A blue NSR Z4 in anglewinder configuration with the same type of solder-onto-the motor MOSFET power control board as shown earlier for the yellow F1 car. Wiring from left to right: motor PWM (white), brake PWM (blue), 0 Volts DC (Black) and +12 Volts DC (Red).



Next, on to the digital speed read-out.

c

Do these have ICP or do they work on another system?