Maker Pro
Maker Pro

Closed loop for two brushless motors

babba369

Feb 15, 2023
2
Joined
Feb 15, 2023
Messages
2
Hello everyone,
I need to buy a board (STM32?) like Arduino in order to read in input two RPM values from two different RPM sensors and to send in output two PWM signals to two different ESC (Electronic Speed Controller) that will drive two brushless motors.
Basically I need something that will provide these features:
  • 12-bit resolution
  • read in input two RPM values
  • send in output two PWM values
  • control frequency in the order of 2 kHz
  • USB-connection in order to load the software from my PC
I am very sorry, total noob in Electronics!
Thanks in advance
 

Minder

Apr 24, 2015
3,479
Joined
Apr 24, 2015
Messages
3,479
Not really a suitable project for someone who is a 'total noob to Electronics'?
 

crutschow

May 7, 2021
857
Joined
May 7, 2021
Messages
857
I am totally agree with you, this is a work for a master thesis.
Then this is classified as homework and should be in that forum.

With that, we don't do homework, so you need to show us you approach to solving the problem and we will help.
 

danadak

Feb 19, 2021
784
Joined
Feb 19, 2021
Messages
784
Consider this :



The above kit is for PSOC 4 but if you port it to PSOC 5LP that has a USBUART in it that is
very easy, with example project, to implement a USB serial link. The 5LP board also
debugs/programs thru USB. Board to start with would be CY8CKIT-059, $ 15. PSOC 4 board
has USB for debug/[program, but not a USB for USBUART if you needed that capability. PSOC
5LP has all that capability and more.

What is in a single chip SOC PSOC 5LP, multiple copies of these resources in many cases :

1676483640264.png

1676483687463.png

On web many articles about using PSOC 4 for motor control. PSOC 4 is basically a subset
of 5LP.

Compiler and IDE (PSOC Creator) free.



Regards, Dana.
 
Last edited:

hevans1944

Hop - AC8NS
Jun 21, 2012
4,889
Joined
Jun 21, 2012
Messages
4,889
Another excellent post by @danadak. Anyone working towards a degree of master of science in electrical engineering should be able to follow Dana's suggestions.

If, OTOH, this project is for a degree of master of science in mechanical engineering, or any other field remotely related to engineering... well, good luck! The fairly recent study of electronics merged with mechanics is called mechatronics. In your state, Michigan Tech (Michigan Technology University) offers a masters degree in this field.

I do not have an advanced degree, but I have been engaged in mechatronics design since the 1960s while working towards my Bachelor of Electrical Engineering degree (BEE, '78, University of Dayton). A mechatronics design can also involve other disciplines, such as chemical engineering, materials engineering, or vacuum science, before anything useful is produced. A modern oil refinery is just one of many industrial examples.
 
Last edited:

Minder

Apr 24, 2015
3,479
Joined
Apr 24, 2015
Messages
3,479
The title of the thread indicates Mechatronics, " Closed Loop for Two Brushless Motors"
Done consistently in most CNC applications, via PID.
 

hevans1944

Hop - AC8NS
Jun 21, 2012
4,889
Joined
Jun 21, 2012
Messages
4,889
Done consistently in most CNC applications, via PID.
Virtually all closed-loop negative feedback controls are implemented with some form of PID (Proportional + Integration + Differentiation) error correction, but the OP is mainly concerned with controlling two BrushLess DC (BLDC) motors. This is an entirely separate design consideration that is handily solved by the Cypress kit mentioned by @danadak in his post #6. Of course other solutions are also possible. Since this is homework, I will leave their discovery as an exercise for the student.

With regard to closed-loop control, negative feedback signals are still mainly analog because the transducers are mostly analog: LVDTs (Linear Variable Differential Transformers) for position and velocity measurements, or string-potentiometers, or shaft speed rotation sensors are a few examples. Digital versions of these analog transducers also exist and are used in mechatronics, but the methods used to interface them are varied and many. Digital closed-loop control via negative feedback has been playing "catch up" since about the middle of the 20th Century, with the advent of fast analog-to-digital converters for input signals and fast digital-to-analog converters for output signals, along with fast microprocessors to implement control algorithms, but there is still usually the necessity to convert analog transducer signals to digital form. There is art and design compromise involved in that.

I think @Minder hit the nail on the head with his post #2: "Not really a suitable project for someone who is a 'total noob to Electronics'?" And was this a "drive by" poster only looking for a quick answer?
 

Minder

Apr 24, 2015
3,479
Joined
Apr 24, 2015
Messages
3,479
With regard to closed-loop control, negative feedback signals are still mainly analog because the transducers are mostly analog: LVDTs (Linear Variable Differential Transformers) for position and velocity measurements, or string-potentiometers, or shaft speed rotation sensors are a few examples. Digital versions of these analog transducers also exist and are used in mechatronics, but the methods used to interface them are varied and many. Digital closed-loop control via negative feedback has been playing "catch up" since about the middle of the 20th Century, with the advent of fast analog-to-digital converters for input signals and fast digital-to-analog converters for output signals, along with fast microprocessors to implement control algorithms, but there is still usually the necessity to convert analog transducer signals to digital form. There is art and design compromise involved in that.
For some many decades now I have been using the popular quadrature encoder for PID servo loop feedback.
And In DIY products using them with the likes of the Galil motion cards, where the encoder response feedback is in the order of 18mhz now.
 
Top