wckReadPos

[chickenkai]

Hi

I programming a code in C# with RobobuilderLib.dll

Now I use a trackBar to control the servo motor to move

But I Found a problem:

when I pull the trackBar slowly and use the function wckReadPos to

read the wck posture, the value is inaccuracy within 5 degrees,

but if I pull the trackBar fast and use wckReadPos the value is

inaccuracy would increase a lot, bigger than 10 degrees,

how can I solve this problem?

thanks!

[l3v3rz]

Its probably a timing issue - if you read servo too quickly it won't have settled , try a delay before reading or multiple wckReadPos until it settles.

[chickenkai]

how can I do?

Like this?

Code: Select all

if (i == 11)
{
     rbWCK.wckMovePos(11, Convert.ToByte(trackBar1.Value), 2);
     textBox_pos.Text = Convert.ToString(trackBar1.Value);
     rbWCK.delay_ms(200);
     if (rbWCK.wckReadPos(11))
     {                   
            richTextBox1.Text = "Servo 11 end:" + Convert.ToString(rbWCK.respnse[1]);       
      }
      else
     {
      textBox_pos.Text = "Servo 11 NOT CONNECTED";
      }
}


[l3v3rz]

hope this isn't a trick question - but yes - exactly. you may find you can reduce the value from 200ms down to may be 50-100ms. It partially depends on how big the move is, the servos have a velocity, so the bigger the move the longer it takes before it settles.

[chickenkai]

I tried this:

Code: Select all

if (rbWCK.wckReadPos(11))
{
   if (rbWCK.respnse[0] == 0)
  {
       rbWCK.wckMovePos(11, Convert.ToByte(trackBar1.Value), 2);
       textBox_pos.Text = Convert.ToString(trackBar1.Value);
       rbWCK.delay_ms(50);
        if (rbWCK.wckReadPos(11))
            {
               richTextBox1.Text = "Servo 11 end posture:" + Convert.ToString(rbWCK.respnse[1]);
             }
   }                       
}
else
{
   textBox_pos.Text = "Servo 11 NOT CONNECTED";
}
 

And I found that as same condition as I mentioned.

If I suddenly pull the trackBar fast and use wckReadPos the value is

inaccuracy would increase a lot, bigger than 10 degrees.

If I increase the delay time, the motor would not move smoothly.

It's so strange.