Hiwin D1 - Page 31

D1 Servo Drive User Manual Operation Principles
HIWIN MIKROSYSTEM CORP. 3-7
MD20UE01-2109
(1) Position
Optical scale or encoder provides the servo drive with the current position of motor. Units used for
different motion types are as below. In D1 servo drive, reference position means position command.
Reference position is calculated by the path generator according to the related parameters. Target
position is the desired position set by user or controller. After target position is set, it is calculated by
the path generator before the servo drive commands motor to move.
Table3.4.1
Motion
Unit
Linear Motion
um, mm and m
Rotary Motion
Encoder count
(2) Velocity
Velocity is the displacement per unit time. Units used for different motion types are as below.
Table3.4.2
Motion
Unit
Linear Motion
um/sec, mm/sec and m/sec
Rotary Motion
count/sec, rps and rpm
(3) Acceleration
Acceleration is the change in velocity per unit time. Units used for different motion types are as
below.
Table3.4.3
Motion
Unit
Linear Motion
um/sec
2
, mm/sec
2
and m/sec
2
Rotary Motion
rps
2
(4) Smooth factor
When acceleration or deceleration is dramatically increased or decreased in a short time, the force
applied to the motor and load will be increased or decreased accordingly. Smooth factor is used to
create S-curve or T-curve velocity profile to moderate the impact from such change. The setting
range of smooth factor is from 0 to 500. Increase the value of smooth factor to have S-curve velocity
profile and smaller impact. Decrease the value of smooth factor to have T-curve velocity profile. Set
smooth factor to 1 to disable smoothing function. In some occasions, settling performance can be
enhanced by increasing smooth factor since the impact from the motor force is reduced. However,
smoother motion may have longer move time. Find the suitable value of smooth factor by executing
test run and tuning on your machine. When smooth factor is set to 0, the motion protection of the
servo drive is disabled.