Input Grapher

Defines values that vary during the simulation . Values often vary by time, but forces or torques can also vary by other independent variables. Use the Input Grapher to save value definitions for later and, if appropriate, repeated use.

Note: The Undo feature is not available in the Input Grapher. Also, Input Grapher parameters, like Dynamic Part Motion and Output Grapher parameters, are not available in the Parameters dialog box.

Access:

Click the varying magnitude icon in selected text entry boxes. If the icon is not there by default, click if it is at the right of the text-entry box and select Input Grapher from the menu that appears.

The Input Grapher contains several parts.

• Graph region
• Commands
• Display region
• Sector starting and ending point coordinates
• Property of the selected sector
• Out of definition sector description
• Freeing conditions and application conditions
• Context menu options

Graph region

cursor position

Displays the X and Y coordinates of the current position of the cursor. This value appears above the graph region. Use the cursor position to help you place points for curve sectors.

curve

Displays how the dependent variable (the values for the text entry box that opened the Input Grapher) along the Y axis varies according to the X axis variable. The X axis variable is time. For Y axis variables other than imposed motion, like internal forces and moments, external forces and moments, and spring stiffness , the X axis variable can be any of the available output variables. A curve is divided into curve sectors, with the area between two points constituting a sector. When a particular curve sector is selected, it turns yellow.

Panning

To pan inside the graph region, click and hold the middle mouse button or wheel, and drag to move the graph as required.

Zooming

To zoom inside the graph region, scroll the mouse wheel. Think of the zoom behavior as an extension of your arm and hand. To examine something closely you bring your hand closer to you. Rolling the mouse wheel back toward you zooms in. Rolling the mouse wheel away from you zooms out, just as moving your hand away from you enables you to see more of what it is holding.

Note: When zooming, the graph axis display and scale adjust so that the labels continue to be easily read.

Zoom All

To zoom all, see the whole curve, right click in the graphic region and select Zoom All or double-click the middle mouse button.

Zoom Window

Left-click to define a frame around the zone you want to zoom in to. The software changes the size of the curve so that the area in the frame fills the graph region.

Note: Clicking resizes the curve to fit inside the graph region.

Reference

Reference

Opens the Select reference dialog box, enabling you to set the independent variable for this curve. The Select reference dialog box shows all variables available for use as X axis variables. Select only one X axis variable for a curve. By default,Time is the X axis variable. This field is disabled when defining values for imposed motion, because time is the only X axis variable for imposed motion.

Commands

	Recenters the curve in the graph region.
	Deletes the curve definition and all points defining curve sectors.
	Opens the Open dialog box. Load a curve definition from a file with a .cgd extension.
	Opens the Save as dialog box. Save a curve definition to a file with a .cgd extension.

Display

This group of fields is available only when you use the Input Grapher to define values for an imposed motion.

	Displays the curve of the position over time. This curve is red. Unavailable if position is the driving variable for this imposed motion.
	Displays the curve of the velocity over time. This curve is green. Unavailable if velocity is the driving variable for this imposed motion.
	Displays the curve of the acceleration over time. This curve is blue. Unavailable if acceleration is the driving variable for this imposed motion.

Sector starting and ending points

This group of fields appears when there is an active curve sector. Use this feature to view and edit the exact coordinates of the starting and ending points.

Note: Points on a curve are red when they are selected and blue when they are not selected.

Starting point X1	Edits the X coordinate of the starting point of the selected sector.
Starting point Y1	Edits the Y coordinate of the starting point of the selected sector.
Ending point X2	Edits the X coordinate of the ending point of the selected sector.
Ending point Y2	Edits the Y coordinate of the ending point of the selected sector.

Property of the selected sector

This group of fields appears when there is an active curve sector. Use this feature to define the curve properties of the selected sector.

Note: The selected curve sector is yellow.

Active	Indicates that this sector does not have any conditions. The curve definition entered here is always active.
Free	Indicates that this sector has no values defined. For an imposed motion law, it is a way of freeing a degree of freedom.
Condition	Indicates that there is one or more conditions to this definition of this sector. For a force, the force is applied if the condition is verified. For an imposed motion, the degree of freedom is freed if the condition is verified.
	Edits the application conditions. Opens the Applications conditions dialog box and edits the conditions when the selected sector is free or has the defined shape.
	Makes the previous sector active.
	Makes the next sector active.
List of available laws	Lists various laws you can use singly or in combination to define the curve in a sector. Law selections are: Linear ramp Cubic ramp Cycloid Sine Polynomial Harmonic Modified sine Modified trapezoid Spline Formula Use the arrow at the right of this box to show a menu that lists available laws. Note: The formula law is not available for imposed motion.
	Replaces the law in the List of sector's laws box with the law displayed in the List of available laws box.
List of sector's laws	Lists laws that define the curve in the selected sector.
	Adds the law selected in the List of available laws box to the List of sector's laws box.
	Deletes the law currently displayed in the List of sector's laws box. You can access a menu from the arrow at the right of the List of sector's laws box. Select the law you want to delete.
Other fields in the Input Grapher dialog box vary according to the law displayed in the List of sector's laws box.
Slope	Sets the slope of the curve in the selected sector. Available when Linear ramp, Cubic ramp, Cycloid, Harmonic, Modified sine, or Modified Trapezoid appears in the List of sector's laws box.
Amplitude	Sets the amplitude of the oscillatory curve in the selected sector. Available when Sine appears in the List of sector's laws box.
Frequency	Sets the frequency of the oscillatory curve in the selected sector. Available when Sine appears in the List of sector's laws box.
Phase	Sets the phase of the oscillatory curve in the selected sector. Available when Sine appears in the List of sector's laws box.
Interpolation by least squares method	These fields are available when Polynomial appears in the List of sector's laws box. There are two methods for specifying the values: Method 1: Specify the coefficient values Enter the values for a0, a1, a2, a3, a4, a5. Method 2: Import a text file opens the Open dialog box, enabling you to import a file that defines this polynomial. Order sets the order of the polynomial for the curve in the selected sector. calculates the constant value and the values at the first five orders of this polynomial. a0, a1, a2, a3, a4, a5 shows the constant value and the values at the first five orders of this polynomial. You can edit these values if necessary. The text file should be formatted as follows: //comments - comment lines are optional. x1 y1 - list of points, as many as you need. ... - one point per row or line. xn yn
	Displays the Open dialog box, enabling you to import a .txt file that defines a spline. Use this feature to recreate a curve sector defined in an earlier Dynamic Simulation session quickly Available when Spline appears in the List of sector's laws box. The spline text file requires a specific text definition, as follows: Note: You cannot add other laws to a sector defined by a spline. Also, if you replace a sector's law by a spline, then the initial and final slopes are automatically collected from the previous and following sectors, but can be manually modified later. If you want to use a text file containing tangency points, structure the file as follows: // comments - you may include one or more lines of commentary in the file. Each line must start with “//”. Comment lines are optional, but provide value by enabling you to note the purpose of the spline. [Tangents] T1 T2 - specify the value of the tangent for the beginning (T1) and ending (T2) points of the sector. These values are shown as the “initial” and “final” slope in the user interface. If no value is supplied, an implied tangent value of 0.0 (horizontal tangent) is assumed. As with comment lines, this line is optional, but as noted, where no tangent value is given some assumptions must be made. X 1 Y 1 - the list of point coordinates, you can list as many points as you need. Each point set must be on a different row. Sample text file: // // Simulation input spline points // Value: Joint Torque (N mm) // Reference: Time s [Tangents] -3.40775 -5.27803 +0.000 +0.000 +4.313 +1.510 +7.954 -9.756 +1.000 +0.000
	Displays the Save As dialog box. Save a .txt file that defines this spline. Use this function to save a curve sector for use in a later Dynamic Simulation session Available when Spline appears in the List of sector's laws box.
Initial slope	Sets the initial slope of the curve in the selected sector. Available when Spline appears in the List of sector's laws box.
Final slope	Sets the final slope of the curve in the selected sector. Available when Spline appears in the List of sector's laws box.
Points table	Displays the X and Y coordinates of every point in this spline. This table is available when Spline appears in the List of sector's laws box.
Formula box	Opens a text entry box. Enter a formula for the curve in the selected sector. Available when Formula appears in the List of sector's laws box.

Out of definition

This group of fields appears when you click outside the entire curve. Use this function to describe the part of the curve on the left of the first point or on the right of the last point.

Curve addition position	Sets the position of this curve addition.
Freeing conditions	Available only when you use the Input Grapher to define values for an imposed motion. Specifies that the curve addition is free (without definition) under certain conditions and opens the Freeing conditions dialog box.
Applications conditions	Available when you use the Input Grapher to define values for anything other than an imposed motion. Specifies that the curve addition has the selected shape under certain conditions and opens the Applications conditions dialog box.
	Sets the application conditions. Specifies that the curve sector has the defined shape under certain conditions and opens the Applications conditions dialog box.
Curve shape options	Specifies the shape of the additional part of the curve added when the Y axis variable goes outside the entire curve during simulation. Select one and only one shape. The default is a constant value equal to the Y value at the starting point of the entire curve (when you select On the left of the first point for the curve addition position) or the value at the last point (when you select On the right of the last point for the curve addition position).
Constant value	Specifies that the curve addition shape is a constant value equal to the value at the starting point of the entire curve (when you select On the left of the first point for the curve addition position) or the value at the last point of the entire curve (when you select On the right of the last point for the curve addition position). This setting is the default setting.
Constant slope	Specifies that the curve addition shape is a line with a constant slope equal to the slope of the first curve sector (when you select On the left of the first point for the curve addition position) or the slope of the last curve sector (when you select On the right of the last point for the curve addition position).
Modulo	Specifies that the curve addition shape reproduces the shape of the current curve from the first point to the last.
Cyclical	Specifies that the curve addition shape reproduces the shape of the current curve from the starting point to the last point. If you select Cyclical, you can and must specify the starting point. This shape, a modified modulo, is available only if you select On the right of the last point for curve addition position.
Start	Opens the Selection of the starting point dialog box. Specify which point you want to use as the start of the Cyclical shape. Select only one point. This parameter is available only when you select Cyclical as the curve addition shape.
Free	Specifies that the curve addition is free (that is, has no shape). This shape is available only if you select On the right of the last point for curve addition position.

Freeing conditions and application conditions

The Freeing conditions dialog box an d the Application conditions dialog box both have the following fields:

Variable	Opens the variables browser. Select one.
Condition	Suggests a list of conditions such as equal, greater or equal, less than or equal. Select one.
Value	Opens a text entry box. Set a value.
	Adds a condition line. You can choose between "and" and "or" for the connector between two conditions.
	Opens the condition selection box. Delete a condition line.
	Deletes the selected condition line. To edit a condition line, delete it, close the condition selection box, and add the correct condition.
	Closes the condition selection box. However, the software does not impose the conditions until you click OK.

Together, the above specify the conditions under which the curve is free or takes the defined shape.

In the case of a force, the force is applied if the condition is verified. In the case of an imposed motion, there is the condition of freedom. The degree of freedom is freed if the condition is verified.

Context menu options

The following are the options that may appear on a context menu.

Add Point	Adds a point to the curve. Available when you right-click anywhere in the graph region except on a point.
Grid	Displays a grid in the graph region. Available when you right-click anywhere in the graph region.
Lock Point	Prevents the selected point from being deleted or moved. To move one point on the curve without affecting the two adjacent points, first lock the points you want to remain fixed. An anchor icon shows that a point is locked. Available only when you right-click a point in the graph region.
Remove Point	Deletes the selected point. Available only when you right-click a point in the graph region.
Unlock Point	Allows the selected point to be deleted or moved. Available only when you right-click a point in the graph region.
Zoom All	Resizes the graph view so that the entire curve appears in the graph region. To Pan the graph region click and drag the middle mouse button or wheel. To Zoom in or out, use the mouse wheel. To zoom in a specific area use the Zoom Window command. To Zoom All, double-click the middle mouse button.