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ModifiedTrapezoid is a Traditional MotionLaw SegmentEditor AND BlendPoint EditorCAN specify the: •Position at the START of the segment. The Position value usually flows from the PreviousSegment. CAN specify the: •Position at the END of the segment. CANNOT specify the: •The Velocity values at the Start and End are 0 units/s •The Acceleration values at the Start and End are 0 units/s2 •The Jerk values are a function of the Positions at the Start and End of the segment, and duration of the segment. See also: Tutorial 4: Edit the Start of a Traditional Segment See also : Tutorial 8: 'Asymmetrical Motion Laws'. 

ModifiedTrapezoid•Symmetrical •Continuous in Position, Velocity and Acceleration, •Finite Step of Jerk at its Start and End •Continuous in Jerk at crossover In acceleration, the segments are: •1/4 Sine function for 0.125 of the SegmentWidth • ConstantAcceleration for 0.25 the SegmentWidth •1/2 Cosine function for 0.25 the SegmentWidth  crossing the midpoint of the motion law at the midpoint of this segment • ConstantAcceleration for 0.25 the SegmentWidth •1/4 sine wave function for 0.125 of the SegmentWidth MotionLaw MotionCoefficients: •Velocity Coefficient: Cv = 2 •Acceleration Coefficient: Ca= 4.89 •Jerk Coefficient: Cj= ±61.43 (Start, Finish and crossover). Application NotesThe Modified Trapezoidal motion law has finite jerk throughout the segment. It has an average peak nominal acceleration compared to the other Traditional MotionLaws. Dynamic Performance This MotionLaw is a good general purpose type particularly in applications where the period ratio is above about 5. It is not good in applications where the input drive has backlash or is relatively flexible. As long as the drive satisfies these conditions, then this segment exhibits low residual vibrations. Pressure Angle Considerations This one of the Traditional MotionLaws that produce a relatively large pressure angle  and so might need a large cam for a given lift and preprescribed maximum pressure angle. Drive Torques This MotionLaw exhibits a rapid reversal of acceleration at the crossover (mid) point. Only the ConstantAcceleration MotionLaw is more rapid, of the Traditional Segments. It is unsuitable to drive heavy masses at high speeds. The rapid reversal of torque may give rise to severe vibrations and shock loading especially if the period ratio is less than 10. 