MechDesigner Reference & User Interface > 2.2 Mechanism-Editor > Function-Blocks > Kinematic Function-Blocks

Measurement FB

Use a Measurement FB to measure between sketch-elements in the same or different Parts.

You can measure the:

•Length of a Line, CAD-Line

•Radius of a Circle, arc

•Distance between two Points** §

•Distance between a Line* and a Point**

•Distance between two parallel Lines*

•Angle between two Points** §

•Angle between two Lines*

•Angle between three Points**

The data at the output-connector of the Measurement FB includes the:

•dimension being measured, and the

•the first and second motion-derivatives of the dimension.

§ - There are two(2) output-connectors when you measure between any two Points* - see more details below

* Line, CAD-Line, X-axis, Y-axis.

** Point, start-Point, end-Point, center-Point, and/or Motion-Point.

Add Measurement FB

Measurement FB between two Points

1.Click Kinematics FB toolbar > Measurement FB

1.Click Function-Blocks menu > Measurement (FB)

2.Click the sketch-element

2.Click the sketch-elements that you want to measure

3.Click the graphics-area.

The Measurement FB and Dimension are now in the graphics-area.

In this example, the Measurement FB and the Dimension is between two Points

Note:

In the graphics-area, to move the:

Measurement FB – Drag the FB

Measurement Dimension – CTRL + Drag the FB or the Dimension.

Measurement FB

How to use the Measurement FB:

Use the data at the output

You can connect a wire from the output-connector of a Measurement FB:

... to plot the Position, Velocity and Acceleration of the dimension with a Graph FB - see Note 1 below

... to the input-connector of a Motion FB. The motion-data from the Measurement FB is then the independent variable for a Motion in MotionDesigner, More typically, the independent variable is the output of a Linear-Motion FB - see Note 2 below

... to the input-connector of a Motion-Dimension FB - see Note 2 below

Note 1:

To plot the Dimension, First Motion-Derivative, and the Second Motion-Derivative in the same graph:

1.Drag a wire from the same output-connector of the Measurement FB three times to different input-connectors of a Graph FB,

2.Use the Y–axis display options in the Graph Interface to display the three different motion-derivatives.

Note 2:

Check the messages in the Feedback-Area.

“1 Mechanism dependencies detected”. This means, that the motion of a kinematic-chain is a function of (dependent on) the motion (measurement) of a different kinematic-chain. It is usually called Motion-Dependency.

Note the * and ** in the details below: * Line, CAD-Line, X-axis, Y-axis ** Point, start-Point, end-Point, center-Point, Motion-Point.
Image	Sketch-Elements	Measurement Dimension
Length or Radius	1.Click a Line or CAD-Line	Length of the Line*
Length or Radius	1.Click a Circle or Arc	Radius of the circle or arc.
Distance - Point & Line	1.Click a Point** 2.Click a Line*	Perpendicular Distance between the Line and Point.
Distance - 2 Points	1.Click a Point 2.Click a Point	A Measurement FB between two Points** has two output-connectors: - Top output-connector: Distance between the two Points, and first and second motion-derivatives - Bottom output-connector: angle between the two Points, and first and second motion-derivatives
Distance - 2 Points

Angle between three(3) Points - Internal Angle and External Angle. Point, start-Point, end-Point, center-Point, Motion-Point.
Image	Sketch-Elements	Measurement Dimension
Internal Angle - 3 Points	Three Points 1.Click 'Apex' Point 2.Click Point 3.Click Point**	Internal Angle The angle is from to in a Counter-Clockwise direction.
External Angle - 3 Points	Three Points 1.Click 'Apex' Point 2.Click Point 3.Click Point**	External Angle The angle is from to in a Counter-Clockwise direction.

Angle between two(3) Lines* - to measure 8 different angles
Image	Sketch-Elements	Measurement
Angle - 2 Lines	Two Lines 1.Click a Line* 2.Click Line*	Angle - from eight(8) possible Angles.
To display one of eight angles: Before you click in the graphics-area to place the Measurement Dimension and FB ... ... move your mouse-pointer around the apex of the two lines: CASE 1: Counter-clockwise : 4 angles < 180° : the Acute, Obtuse, Supplementary and Vertical angles CASE 2: Clockwise : 4 angles > 180° : the reflex angles - or the angles that are external to those angles of CASE 1.
Video: Eight Measurement Angles between two Lines: Add Angle Dimensions between two Lines