I am using stepper motors as indicator instruments in an anemometer project I have made.
There is a problem in that the stepper motor driving the wind speed dial tends to loose steps, but only in one direction. Under ordinary circumstances the wind may vary from say 2 to 10 knots, when the wind increases I step the motor to move the indicator (needle) and when it decreases I step the motor back the same number of steps. However after a period of time there is an increasing error in which the needles slowly moves down in the range and eventually past the zero point.
It is as if it takes more steps to move up than to move down the same distance on the scale.
I count the up steps and the down steps and all seems in order as regards to the arithmetic of my program.
This is very puzzling and somewhat frustrating, any comments greatly appreciated.
John
There is a problem in that the stepper motor driving the wind speed dial tends to loose steps, but only in one direction. Under ordinary circumstances the wind may vary from say 2 to 10 knots, when the wind increases I step the motor to move the indicator (needle) and when it decreases I step the motor back the same number of steps. However after a period of time there is an increasing error in which the needles slowly moves down in the range and eventually past the zero point.
It is as if it takes more steps to move up than to move down the same distance on the scale.
I count the up steps and the down steps and all seems in order as regards to the arithmetic of my program.
This is very puzzling and somewhat frustrating, any comments greatly appreciated.
John