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Mini24 with Arduino SelectMultipleTarget

Hi,
recently I just bought Mini Maestro24 to use with my Arduino Mega2560 to control multiple servo. I am wondering if the function SelectMultipleTargets is applicable for arduino and do you have any sample for that?

Daniel

Hello, Daniel.

It sounds like you are asking about using the Set Multiple Targets command (which is described in the “Serial Servo Commands” section of the Maestro user’s guide) with an Arduino. Is that correct? If so, you should be able to use that command by calling the setMultiTarget function provided by our Maestro library for Arduino.

- Patrick

Thanks Patrick. I manage to get SetMultiTarget to work but I run into the same issue as this guy.


Sometimes the servos will go to the desired position and jitter and sometime just jerk but cannot go to the desired position.

let me explain how I wiring my Mini Maestro ,Mega2560 and Servo.

  1. Mini maestro-24 connect to usb=> to my PC.
  2. Mini maestro-24 get servo power from external power supply DC6V. I am sure that this external power supply has enough power supply to my 4 servos
  3. Mega2560 connect to usb=> to my PC.
  4. ground is connect from Mega2560=>Maestro-24 and external power supply
  5. Maestro-24 RX connect to Meag2560 pin 11 , Maestro-24 TX connect to Meag2560 pin 10
  6. 4 units Servo connect to Maestro-24 at pin 0-3
    I monitor the error log while the Arduino is communicating with the maestro, the maestro works perfectly and all the servos go to the desired positions no problem - no errors listed. Do you guys have any idea what the problem is? below is my code.

#include <PololuMaestro.h>
#include <SoftwareSerial.h>
SoftwareSerial maestroSerial(10, 11);
uint16_t BeginArray[]={4000,4000,4000,4000};
uint16_t EndArray[]={7000,7000,7000,7000};
//MicroMaestro maestro(maestroSerial);
MiniMaestro maestro(maestroSerial);

void setup()
{
pinMode(10,INPUT); //set rx (or pin 0) as input
pinMode(11, OUTPUT); //set tx (or pin 1) as output
maestroSerial.begin(115200);
maestro.setSpeed(0, 100);
maestro.setAcceleration(0,60);
maestro.setSpeed(1, 100);
maestro.setAcceleration(1,60);
maestro.setSpeed(2, 100);
maestro.setAcceleration(2,60);
maestro.setSpeed(3, 100);
maestro.setAcceleration(3,60);
}

void loop()
{
maestro.setMultiTarget(4,0,BeginArray);
delay(4000);
maestro.setMultiTarget(4,0,EndArray);
delay(4000);
}

Hi,
For more information. if I change the code to move servo 1 by 1 all servos work properly. here is my new code. Any idea?
#include <PololuMaestro.h>
#include <SoftwareSerial.h>
SoftwareSerial maestroSerial(10, 11);
uint16_t BeginArray[]={4000,4000,4000,4000};
uint16_t EndArray[]={7000,7000,7000,7000};
//MicroMaestro maestro(maestroSerial);
MiniMaestro maestro(maestroSerial);
int pos =0;
void setup()
{
pinMode(10,INPUT); //set rx (or pin 0) as input
pinMode(11, OUTPUT); //set tx (or pin 1) as output
maestroSerial.begin(115200);
maestro.setSpeed(0, 100);
maestro.setAcceleration(0,60);
maestro.setSpeed(1, 100);
maestro.setAcceleration(1,60);
maestro.setSpeed(2, 100);
maestro.setAcceleration(2,60);
maestro.setSpeed(3, 100);
maestro.setAcceleration(3,60);
}

void loop()
{
/*maestro.setMultiTarget(4,0,BeginArray);
delay(4000);
maestro.setMultiTarget(4,0,EndArray);
delay(4000);
*/
pos=4000;
maestro.setTarget(0,pos);
delay(400);
maestro.setTarget(1,pos);
delay(400);
maestro.setTarget(2,pos);
delay(400);
maestro.setTarget(3,pos);
delay(4000);
pos=7000;
maestro.setTarget(0,pos);
delay(400);
maestro.setTarget(1,pos);
delay(400);
maestro.setTarget(2,pos);
delay(400);
maestro.setTarget(3,pos);
delay(4000);
}

This sounds like a power supply issue since each servo seems to be working when there is a 400 ms delay between their movements, but will not work when you try to move them all at the same time. To confirm that, can you try your program that uses setMultiTarget with only one servo connected?

- Patrick

it work almost perfect with setMultiTarget with only 1 servo attach. but sometime it still jitters a little bit. Say 1-2 minute once.

Daniel

Can you post more information about the power supply and servos you are using, such as datasheets or links to where you got them? I also suggest you try monitoring your system with an oscilloscope so you look at what is going on. If you have a power supply that can handle more current, can you test it out?

- Patrick