S-curve and Trapezoidal Acceleration/Deceleration

S-curve

If the JerkClosedIn physics, jerk is the rate of change of acceleration; more precisely, the derivative of acceleration with respect to time input of a motion function block is non-zero, S-curve acceleration/deceleration is used. The Acceleration input specifies the maximum acceleration/deceleration reached during changes in velocity. The Deceleration input is unused. The Jerk input specifies the constant rate of change of acceleration and deceleration used to cause a smooth transition to and from maximum acceleration/deceleration.

The Small Jerk Acceleration below is a velocity plot of the acceleration of a move when Jerk is a small value. The smaller the Jerk value, the more gradual the rate of change of acceleration/deceleration when transitioning from one velocity to another.

Small Jerk Acceleration

Figure 5-44: Small Jerk Acceleration

The Large Jerk Acceleration below is a velocity plot of the acceleration of a move when Jerk is a large value. The larger the Jerk value, the more abrupt the rate of change of acceleration/deceleration when transitioning from one velocity to another.

Large Jerk Acceleration

Figure 5-45: Large Jerk Acceleration

Trapezoidal

If the Jerk input of a motion function block is zero, trapezoidal acceleration/deceleration is used. The Acceleration input specifies the linear acceleration rate. The Deceleration input specifies the linear deceleration rate.

The Trapezoidal Acceleration below is a velocity plot of the acceleration of a move when trapezoidal acceleration is used (Jerk = 0).

Trapezoidal Acceleration

Figure 5-46: Trapezoidal Acceleration

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