Each Motion-Law is a mathematical expression that defines how an output variable changes as a function of an input variable.
The mathematical expressions evaluate exactly the displacement, velocity, acceleration, and jerk motion-values. You do not need to know any mathematics.
For convenience, we can separate the motion-laws into three groups.
Note: We list the motion-laws for you in the Motion-Law Selector alphabetically (English spelling).
The Traditional Motion-Laws (also named Standard Motion-Laws) have been used for many years in cam mechanisms for motions that have Rise and Return segments.
The Traditional Motion-Laws are based on:
•Trigonometric Functions, and/or
1.Constant-Acceleration & Deceleration - Polynomial Function
2.Constant-Velocity - Polynomial Function
3.Cubic - Polynomial Function
4.Cycloidal - Trigonometric Function
5.Cycloidal Constant-Velocity 50% -Trigonometric Function
6.Dwell - Polynomial Function
7.Modified-Sinusoid - Trigonometric Functions
8.Modified-Trapezoidal - Trigonometric Functions
9.Polynomial 2-3 - Polynomial Function
10.Polynomial 3-4-5 - Polynomial Function
11.Polynomial 4-5-6-7 - Polynomial Function
12.Polynomial Low Impact Crossover - construct with two Flexible-Polynomial segments
13.Quadratic - Polynomial Function
14.Ramp - Trigonometric Function
15.Simple-Harmonic - Trigonometric Functions
16.Sine-Constant-Cosine Acceleration + SCCA with Constant-Velocity 20%, 33%, 50%, 66%.... - Trigonometric Functions
17.Sine-Squared - Trigonometric Functions
18.Sinusoidal - Trigonometric Functions
19.Triple-Harmonic - Trigonometric Functions
You can edit the Segment Parameters in the Segment Editor to get a motion-law similar to:
20.Flexible Polynomial - it can be used for different motion-laws - see also Special Motion-Laws Flexible-Polynomial, below.
Throw: a motion-law is a rise segment followed immediately by a return segment.
Low Impact at Crossover uses two Flexible-Polynomial segments to give one Rise motion-law. The Jerk is zero when the Acceleration changes to Deceleration.
These meet the needs of specific applications.
25.Y–Inverse-Sinusoid : when applied to the motion of a crank, it gives a constant linear velocity at the tip of a crank. Maximum of one Y-Inverse-Sinusoid segment per crank rotation.
26.CV Inverse Crank : similar to the Y-Inverse-Sinusoid, Not limited to one Crank-Constant-Velocity segment per motion.
27.Flexible-Polynomial - a VERY important and useful motion-law - see also Motion-Laws 20 - 24
28.Ramp - also a useful motion-law - see also Motion-Law 5, Cycloidal CV50
You can import your own motion-values to a List Segment-Type:
Flexible-Polynomial is the default motion-law. It is very powerful. We recommend that you learn how to use it effectively and efficiently.
Traditional Motion-Laws have advantages in some circumstances.
We recommend that you use:
•All Flexible-Polynomials - to give powerful and flexible motion-design possibilities
•All Traditional Motion-Laws - usually the easiest to design a Rise and Return type motion.
•A mixture of Flexible-Polynomial and Traditional Motion-Laws - most difficult motion-design but may have advantages
The Motion-Laws available in MotionDesigner exceed the German Technical VDI-guidelines 2143 Papers (Part) 1 and 2. Also bear in mind, that a motion at a cam-follower or servomotor is usually found by MechDesigner with Inverse-Kinematics. When this is the case, the motion at the cam-follower or servomotor is not the same as the motion-design that is given to the tooling, or Motion-Part.