Rockwell Automation Motion Analyzer Software - Manual (Page 172)

172 Rockwell Automation Publication MOTION-UM004B-EN-P - October 2012
Chapter 2 Sizing Your System
Figure 126 - Trapezoidal Profile
Parameters Description
Smoothness
Used to decrease the discontinuity in the transition from a dwell to motion. Select the
smoothness from the pull-down menu. Three smoothness options are available.
Automatic 0% Jerk (Trapezoidal)
Standard 40% Jerk (Partial S-curve)
Maximum 100% Jerk (Full S-curve)
Accel/Decel Jerk
The percent of time for Acceleration/Deceleration Jerk increases the peak acceleration (and
therefore current) above that of a trapezoidal motion profile. The following values illustrate
the effect of Acceleration/Deceleration Jerk on current. The acceleration of a trapezoidal
motion profile is taken to be 100%.
0% Jerk 100% acceleration and current (Linear or Trapezoidal).
18% Jerk 110% acceleration and current.
33% Jerk 120% acceleration and current.
66% Jerk 150% acceleration and current.
100% Jerk 200% acceleration and current (S-curve).
Apply +ve/-ve
Velocity Limit When you enter the Positive or Negative Velocity Limit for the profile, Motion Analyzer adjusts
the acceleration and deceleration times required to reach the desired velocity limits.
IMPORTANT Smoothness is used to reduce mechanical wear and tear. Due to display
limitations, the
More Options Profile Editor Mode dialog box does not show
infinite jerk at points of velocity discontinuity. Using 0% Jerk time may lead to
premature mechanical failure.