Control ESC with Microcontroller directly?

[Lukinho98]

Hi everyone,

I'm building an RC car (1/8 probably). I bought a 120A ESC by Surpass Hobby and wanted to control it with a Raspberry Pi.
Does anyone have experience with this type of control? I don't want to use the generic joystick Transmitter with the wheel, I want the Raspberry Pi to directly give commands to the ESC through the 3-pin BEC connector.


Any tips appreciated!

 

[Littlemotor]

Hi everyone,

I'm building an RC car (1/8 probably). I bought a 120A ESC by Surpass Hobby and wanted to control it with a Raspberry Pi.
Does anyone have experience with this type of control? I don't want to use the generic joystick Transmitter with the wheel, I want the Raspberry Pi to directly give commands to the ESC through the 3-pin BEC connector.


Any tips appreciated!

View attachment 243734

What’s your reason for not using a purpose built radio, and receiver? What’s your intended use for your “probably 1/8 scale” vehicle you intend to build?

 

[Lukinho98]

What’s your reason for not using a purpose built radio, and receiver? What’s your intended use for your “probably 1/8 scale” vehicle you intend to build?

I'm making a unique RC for long range and want to use custom embedded solution.

 

[Littlemotor]

I'm making a unique RC for long range and want to use custom embedded solution.

How long is “long range”? Is the plan FPV? You’re still going to need to transmit a signal from you to your vehicle…

 

[Lukinho98]

How long is “long range”? Is the plan FPV? You’re still going to need to transmit a signal from you to your vehicle…

I'm happy to chat about the details, but we're steering (wink) off-topic a bit.
I've got everything figured out except the communication between my MCU and ESC. The big question is "What kind of signal should ESC see on its input pin?"

 

[Littlemotor]

I'm happy to chat about the details, but we're steering (wink) off-topic a bit.
I've got everything figured out except the communication between my MCU and ESC. The big question is "What kind of signal should ESC see on its input pin?"

Ok….. it’s relevant to your OP, so… There’s about eleventybillion reasons the “generic” radio’s have been the goto for the past 60yrs, and I’m simply inquiring why you don’t believe those apply to your “unique 1/8 vehicle”.. There’s usually no need to reinvent the wheel if you’re new to this-that’s all bud.. Good luck with it.

 

[Lukinho98]

Ok….. it’s relevant to your OP, so… There’s about eleventybillion reasons the “generic” radio’s have been the goto for the past 60yrs, and I’m simply inquiring why you don’t believe those apply to your “unique 1/8 vehicle”.. There’s usually no need to reinvent the wheel if you’re new to this-that’s all bud.. Good luck with it.

The questions you were asking weren't relevant to what I was looking for, which is help from someone with experience in embedded RC. If you're not able to help with that, that's totally fine. Thanks anyway, and take care.

 

[Lukinho98]

Very mature @Littlemotor
Anyways, closing this thread and opening a new one due to your passive-agressive comments overcrowding the thread.

 

[TeknoJ]

I don’t think anyone here has done this. I think you need to find a more raspberry pi specific forum.

 

[Littlemotor]

Very mature @Littlemotor
Anyways, closing this thread and opening a new one due to your passive-agressive comments overcrowding the thread.

Passive aggressive? I asked you questions bud. It’s a DISCUSSION forum, an I’m interested in what you’re looking to do…

 

[Lukinho98]

I don’t think anyone here has done this. I think you need to find a more raspberry pi specific forum.

To be fair, it does not matter if it is Rpi, it is just what I'm using.
I'm really interested in signals that make the ESC go forward/backward.

 

[TeknoJ]

Very mature @Littlemotor
Anyways, closing this thread and opening a new one due to your passive-agressive comments overcrowding the thread.

We will find you

 

[TeknoJ]

To be fair, it does not matter if it is Rpi, it is just what I'm using.
I'm really interested in signals that make the ESC go forward/backward.

That I don’t personally know, which is why I use a transmitter and receiver that do all that thinking for me.

 

[TeknoJ]

The 3 pin connector is a throttle signal not a BEC.
I would also like to know more

 

[Lukinho98]

The 3 pin connector is a throttle signal not a BEC.
I would also like to know more

The manual says "connect BEC wires with the receiver". Also it has +6.1V/3A output and the signal wire on a single connector. It's definitely BEC.

 

[WickedFog]

It is a PWM signal.

 

[Lukinho98]

It is a PWM signal.

Yeah, I figured that it is some kind of PWM. More curious about the frequency, duty cycle and logic behind how ESC understands the signal. Like, does more duty cycle mean more speed? how does it know if I want to reverse? etc.

 

[WickedFog]

Yeah, I figured that it is some kind of PWM. More curious about the frequency, duty cycle and logic behind how ESC understands the signal. Like, does more duty cycle mean more speed? how does it know if I want to reverse? etc.

50Hz. No idea on the other stuff. Maybe try asking chatgpt? You can generally find answers with that, but I don't know. Are you trying to build an automomous RC?

 

[TeknoJ]

It is a PWM signal.

Thank you.

 

[Lukinho98]

50Hz. No idea on the other stuff. Maybe try asking chatgpt? You can generally find answers with that, but I don't know. Are you trying to build an automomous RC?

The first thing I did was ask chatGPT and it said 50 Hz and some arbitrary amount of microseconds which it pulled out of its donkey.
I am trying to build a long range, video transmission RC, which is why I'm inquiring about this signal.