2022-06-14 16:20:05 d.janssen@reknow.de

Hi,

I'm using a DYNAMIXEL 2XC430-W250-T an controlling it through an Arduino Shield.

When I tell the servo to go to position 1024 (in steps), the sevo reaches the position nicely when I add some delay after the movement.

When I then ask the servo for its position, it returns values deviating from the target position of 1024.

Please see some of my code below (only the relavant stuff).

void setup()

{

dxl.begin(57600);

dxl.setPortProtocolVersion(DXL_PROTOCOL_VERSION);

dxl.ping(DXL_ID);

dxl.torqueOff(DXL_ID);

dxl.setOperatingMode(DXL_ID, OP_EXTENDED_POSITION);// OP_CURRENT_BASED_POSITION OP_POSITION  OP_EXTENDED_POSITION);

dxl.torqueOn(DXL_ID);

dxl.setGoalPosition(1, 0, UNIT_RAW);  // 0deg position 

delay(1000); 

v = dxl.getPresentPosition(1, UNIT_RAW); // v is -1, 0 or 1 which seems to be ok 

dxl.setGoalPosition(1, 1024, UNIT_RAW); // 90deg position 

delay(1000);

v = dxl.getPresentPosition(1, UNIT_RAW); // v is something between 1019 and 1025 which seems to be a bit unreliable. 

}

I added an agular scale to the servo to check the positions. According the the scale, the servo reaches perfectly the desired positions. Only the feedback from the servo  is sometimes a bit inaccurate. 

So, my questions are:

How can I check, if the servo has reached the target position?

How can I retieve the accurate position of the servo?

Any help would be appreciated!

Thanks in advance, Dirk