Motor Programming Issue

ESK8 Electronics
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1

Alright, so unfortunately this is fairly complicated, but I am using a Turnigy Aerodrive SK3 6374 149kv motor, and a BlueSeries 70A ESC. So I have everything connected, and I’m powering the whole setup off of two 1300mah 3s lipos which have been put in series. I have connected my arduino with a joystick to the ESC (the code is below.) So I power it on, and I “calibrate” the joystick by bringing it to the top (2 beeps) then bring it to the bottom (2 beeps [ wait ] then the ESC counts the cells, and beeps once more.) I release the joystick and the motor starts moving (since the joystick is now in the middle) but when I push the joystick towards the top, the motor doesn’t move any faster, but when I pull it back, it stops. and then, RANDOMLY it will just go full speed (while the joystick is still in the middle), so I pull it back, it slows and then stops. When I release it, the motor spins again at normal speed, and nothing happens when I push it up. Sometimes it will spin at full speed again randomly.

I know this is confusing, so I have attached a video and the code below.

Video

CODE:

#include <SoftwareServo.h> int potentiometer=A0; int potval;

SoftwareServo ESC;

void setup() {

pinMode(potentiometer, INPUT); ESC.attach(9); Serial.begin(9600); ESC.setMinimumPulse(800); ESC.setMaximumPulse(2000); }

void loop() {

potval=analogRead(potentiometer); //potval=map(potval,0,1023,0,180); ESC.write(potval); SoftwareServo::refresh(); Serial.println(potval); }

1 Like
2

Hey I’m new here.

Does an esc work within 1000 - 2000 microseconds instead of 800 - 2000?

Also, it looks like you are writing the potentiometer value to the esc as degrees instead of microseconds. I do not know if the arduino converts this to microseconds.

Edit: sorry went to quick through your code. I did not see the map(potval) part was excluded from your sketch. You are writing the potentiometer value directly to the esc. I think this should first be converted to microseconds like this potval=map(potval,0,1023,1000,2000). Right now the esc is getting values from 0 to 1023 (I think this is your problem but I do not know for sure).

Good luck!

3

I mapped it, like so: potval=map(potval,0,1023,0,180); I tried maping it 1000-2000 but when I did so it just went through a series of weird beep sequences. Still doing the same thing as before though…

4

If you change the value 180 to 179 (potval=map(potval,0,1023,0,179)) ? If you use 0-180 you have 181 degrees instead of 180. Maybe this will solve the problem.

5

Unfortunately the isssue is still there… I am VERY confused as to why this isn’t working…

6

I found this page. The code they are using is almost the same you have. However they do not use the line ESC.setMinimumPulse and ESC.setMaximumPulse.

I also control my motor with an Arduino. But my code is somewhat different because I send a wireless signal to the esc and instead of using ESC.write, I use something like ESC.writeMicroseconds.

7

Hmm, yeah it’s interesting. I KNOW for a fact that this code works on other systems, so I am wondering if there is a compatibility issue, and if I need to get a new motor/esc.

EDIT: They also don’t use SoftwareServo, they just use the regular Servo library. IDK if there is a big difference.

8

I don’t know either. It is really weird. You could try to send the esc a few codes to test it. First the arming signal and then a certain speed for a couple of seconds.

9

To control my ESC via Arduino I use the normal Servo.h library :slight_smile:

10

That could be it! I’m also using the servo.h library.

11

Sorry guys, no luck. Only difference with Servo.h library is that it won’t let me calibrate the potentiometer at the bottom, so it only starts moving when I push the thumbstick up.

12

Is it possible that the issue is that I’m using the 149kv SK3 motor with a 6s setup? Should I buy the 236 SK3 motor instead? Different ESC? I can’t shell out the cash/wait for the VESC to come back in stock, but if there are any recommendations.

13

I don’t think that would cause the problem. If I’m using a single 3s battery my motor still works and I can even ride my board with it. I’m using a 5055 sk3 280 kv motor, it is rated for 6s~10s. The esc I’m using is a HK 90A boat esc. I do not recommend this esc because it may brake hard if you reaplly the throttle while the board is coasting.

Maybe you can use someone else his esc/motor to test what is wrong. Or even test your arduino code on some small drone motor/esc?

14

I have a multirotor, so I may be able to test it on that. My next idea is to use the remote control from my quadcopter to control the esc, and see if something changes. I also want to try another ESC. Unfortunately, I CNC’d my mount for the board, and the bolt hole pattern is specific, if I can find another motor which has the same bolt hole pattern I could look into that. Bolt holes are 32mm apart. NTM Prop drive is 30mm apart… Damn.