Rockwell Automation 999 IMC S Class Compact Motion Controller (Cat. No. 4100-999-122) - Manual (Page 93)

Understanding IMC-S/23x Setups 5-13
Publication 999-122 - January 1997
S Curve
S Curve velocity profiles are most often used when the stress on the
mechanical system and load needs to be minimized. The S Curve
profile, however, sacrifices acceleration and deceleration time
compared to the Trapezoidal. In addition, the speed (velocity) of S
Curve motion cannot be changed once the motion is started except to
zero and the same acceleration and deceleration must be used.
Parabolic
A parabolic velocity profile is most often used to optimize the motor
selection since it conforms most closely to the torque/speed curve for
most motors. The parabolic profile, however, sacrifices acceleration
and deceleration time compared to the trapezoidal profile. In addition,
the speed (velocity) of parabolic motion cannot be changed once the
motion is started except to zero and the same acceleration and
deceleration rate must be used.