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Scorpius Brushless controller
#31

As always it’s about scale of economy. So that’s a fair way off.

www.scorpiuswireless.com
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#32

So to power the Texas Instruments ESC should the team source power off the rails or power from MPD? As PSUs vary, some are PWM, some are not. And as the frequency of the PWM of the power supply is generally unknown would it be better to get the power from the MPD where the frequency can be controlled from say a simple MPD Frequency configuration program? In the analogue world the power is from the controller. In the digital world the equivalent is the car decoder.

I think from memory, and the figures could be wrong, the frequency of the power from chip to motor is: Ninco 500Hz, Scorpius 4KHz, SSD 10Khz, Carrera 15khz. ACD Analog controllers (PWM) put out 30Khz. Average ESC system PWM range is 12-24Khz. Average 18Khz.
Scorpius' frequency can be changed to whatever is required quickly. In fact, we can go to around 20Khz before heat becomes an issue. This gives 10% headroom above the average.

By the way the team's preference is for unsensored motors. Less complexity, far better range (maybe 20:1 unsensored over sensored, and slot car specific), and around 5 times cheaper. The Texas Instruments driver matches this criteria. At this stage of the game the unsensored is a no brainer.

Is the data port method required? No its optional. We can send data or voltage to operate it. Obviously if the team used the data port then power would be required from elsewhere. Options included track power or motor power. If the MPD is used to power the ESC then we can regulate voltage and PWM frequency. Bonus? 

Could the team just use a third party ESC currently on the market. Yes but they are not small. The Texas Instruments unit is 8x6x1.7mm.  Remora is 24.8x16.6 (8 times bigger, OUCH!). Some ESCs are configurable. Most are not.

How are brakes affected? The outcome is not known and would need to be tested. Do BL motors use dynamic braking? Sure do. 

Effects of dead flippers over rails? The  MPD V5 will run with a 100uF cap. This could be upped to a bigger unit if required. What will be the effects on the TI BLDC unit? Unknown at this stage. 

The Texas Instruments BLDC driver has configurable functions, so too the Scorpius MPD. Lots of options here. What unit will configure what? Good question. One could speculate but lets see. It would be better to not have to separately configure the Texas Instruments BLDC unit more than once.

Will the team end up using the Texas Instruments offering or an existing RC type unit? Unknown, but its nice to know a plan B is available.
Will extra filtering or smoothing be required. Possibly.

And lastly the obvious ultimate solution is a purpose made digital chip specifically for (wireless) digital. Is it possible? Yes. Will Scorpius ever develop one? Most likely. When? No idea. It depends mainly when the main toy manufacturers will jump. With everything going brushless its only a matter of time. would the chip be small? no. If it was it would need to be double sided. Either way it wont be a cheap product initially. This is why a separate BLDC driver might be the way to go for now.

Who will be the first? Unknown. But one thing for certain is only one manufacturer has started inroads into brushless applications for digital. Guess who? 

It should also be noted a proven sound, reliable and stable digital system should in place to build off well before venturing into brushless. Again, guess who?

3 choices in this regard:

   
Power from track

   
Power from MPD mosfet drivers.

   
Using typical 3rd party RC style ESC unit

www.scorpiuswireless.com
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#33

So conclusion: I’ve decided the only professional solution is actually a dedicated MPD car decoder for brushless. One neat tidy chip that does brushless motors. And one for non brushed. I’d imagine this will a few years off as there is no real demand currently.
Non censored motors will be catered for. Lets face if if it can handle non sensored it can handle sensored should they get popular.
For now we will use the Remora ESC in conjunction with variable frequency power output from the current MPD. It’s really that simple.
My only concern is the space required and a less than perfect install. 

Remora ESC 24.8x16.4x3.7 below. 
As you can see there’s not much to it it and this could easily fit onto side B of the current MPD.
So Team Scorpius have a long term plan.

   

Rick

www.scorpiuswireless.com
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#34

Couldn’t help myself. I ordered one of these today for John on his recommendation.
A Texas Instruments BLDC development board.
Off their website: 
The MCF8316D evaluation module (EVM) enables users to evaluate the performance of the MCF8316D motor driver. The EVM includes an onboard FTDI chip to convert USB communication, from the micro-USB connector, into UART. An onboard MSP430FR2355 microcontroller (MCU) translates the UART communication into either control signals or I2C formatted data, which is sent to the MCF8316. There are many user-selectable jumpers, resistors, connectors, and test points to assist with evaluating the many features of the MCF8316 IC and the configurable device-specific settings.
As we have 12C we can use the MPD in conjunction with this evaluation board to get a feel on the effect of different PWM frequency affects control and performance. And this is all for senseless motors.
If results are top notch then we could possibly place the TI 8A driver 
(MCF8316A) on Side B of the MPD along with all the other necessary components. The size is just 7x5x2mm. 

Development board:

   

Sensorless FOC.
It’s all about the frequencies.
https://www.ti.com/video/6276805432001

www.scorpiuswireless.com
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#35

Exact percentages of sensored versus sensorless (unsensored) brushless slot car motors are not readily available in current data or industry reports, as this specific niche lacks comprehensive market surveys. However, I can provide insight based on trends and characteristics in the slot car and broader RC motor markets. A look online however shows 99.% of brushless slot car motors are indeed uncensored. 

Brushless motors for slot cars, like those used in RC applications, are predominantly sensorless due to their simpler design, lower cost, and suitability for high-speed performance, which aligns with the needs of most slot car racing scenarios. Sensorless motors are often preferred in slot cars because they require less maintenance, have fewer wires, and are generally more robust in high-speed, high-vibration environments, as noted in discussions about brushless motor applications. Sensored motors, while offering smoother low-speed control (heck I never use below 25% PWM, and my controller is set up that way) and better torque at low RPMs, are more complex and expensive, making them less common in slot car racing. Why would I design a product that has limited application due to lack of  motors and cost up to 6 times the price and introduce more wires when we can simply tune the harmonics?  Of course that takes skill and effort. 

Currently the TI webshop has a glitch but we are aiming to order one asap. Once you learn the TI FOC program it only takes 10 minutes to tune a set up.
We plan to have (if we proceed) firmware for each motor type. Just go to the app, choose your motor and upload the firmware to suit. Although a config program is another possibility.. It works be nice to use the TI chip as they are only $4 in bulk and supply 8A which is more than enough for digital racing.
This could work out nicely also for WAM users who can install this into their car to achieve brushless and by default gain dozens of Scorpius goodies like a full light set, fuel, throttle mapping, OLED screen, telemetry, pit bay option, tacho etc. 
A brushless controller with wireless control? Cool.  Cool

www.scorpiuswireless.com
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#36

Nice to read what's available/ going on with these motors  Wrench

Obviously more "Desk Wavegreen" research in needed  Thumbup
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#37

I’m trying to imagine a brushless driver, Scorpius car decoder, Carrera car decoder, comprehensive light board all in one board 24.8x19.2 instead of 3 seperate boards, complete with opto tacho, OLED, hall sensor, telemetry etc, all wireless. 
I mean is it even possible? I mean it’s a big ask.  Wavegreen

www.scorpiuswireless.com
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#38

Nice to be blazing a trail  Thumbup better than swimming in a wake  Wavegreen
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#39

I must admit it is rewarding.
Turning ideas into reality is fun.   
Even with some hiccups.

Thumbup

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#40

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