Delta RMC101 - Manual (Page 199)

Reference Axis Filtering 4.5
Controller Features 4-13
This limits the velocity to a user-specified maximum, but it still leaves us with a sharp change in the
Target Velocity at the time of the step jump. The Acceleration Limit can be used to address this issue:
In the above graph, the Target Position is smoothed out at the time of the step jump. This curve
should be usable as a reference for RMC100 geared moves. In addition, the Reference Deadband
parameter can be used to remove slight ripple in the Target Position while the input voltage is at rest.
Example 2: Quadrature Reference with Quantization Error
Quadrature references will not see large step jumps in the input as is possible for analog inputs.
However, the quantization error in applications with low rates of quadrature counts per second can
lead to spikes in the reference speed.
Note: This example demonstrates how the reference filter can be used to reduce the effect of
quantization error. However, increasing the resolution of the quadrature encoder (for example, from
a 1000-line to a 4000-line encoder) can dramatically reduce quantization error as well.
The Actual Position curve shown below demonstrates the effect of quantization error when moving at
slow speeds: