constraint modify joint translational
Allows the modification of an existing translational joint.
Format:
constraint modify joint translational |
|---|
joint_name = | an existing joint |
new_joint_name = | a new joint name |
adams_id = | integer |
comments = | string |
translational_ic = | length |
no_translational_ic = | true |
velocity_ic = | real |
no_velocity_ic = | true |
friction_enabled = | enable_friction |
delta_v = | real |
maximum_deformation = | real |
mu_dyn_trans = | real |
mu_stat_trans = | real |
max_fric_trans = | real |
preload_x = | real |
preload_y = | real |
height = | real |
width = | real |
relative_to = | an existing model, part or marker |
i_marker_name = | an existing marker |
j_marker_name = | an existing marker |
Example:
constraint modify joint translational & |
|---|
joint_name = | JOINT__1 & |
new_joint_name = | JOINT__2 & |
adams_id = | 2 & |
comments = | "comment string" & |
translational_ic = | 1.2 & |
velocity_ic = | 1.4 & |
friction_enabled = | preload_only & |
delta_v = | 1.4 & |
maximum_deformation = | 0.02 & |
mu_dyn_trans = | 0.4 & |
mu_stat_trans = | 0.8 & |
max_fric_trans = | 0.15 & |
preload_x = | 1 & |
preload_y = | 1.2 & |
height = | 1.5 & |
width = | 0.8 & |
i_part_name = | part_1 & |
j_part_name = | part_2 & |
location = | 10 , 10 , 5 & |
orientation = | 1 , 2 , 1 & |
relative_to = | ground & |
i_marker_name = | marker_1 & |
j_marker_name = | marker_2 |
Description:
Parameter | Value Type | Description |
|---|
joint_name | An Existing Joint | Specifies the joint to modify. You use this parameter to identify the existing joint to affect with this command. |
new_joint_name | A New Joint | |
adams_id | Adams_id | Specifies an integer used to identify this element in the Adams data file. |
comments | String | Specifies comments for the object being created or modified. |
translational_ic | Length | Specifies the initial translational displacement on a translational or cylindrical joint. |
no_translational_ic | True_only | Specifies that if a "translational" velocity initial condition has been set, to "UNSET" the "translational" velocity initial condition for the specified constraint. |
velocity_ic | Velocity | Specifies the initial translational velocity on a translational or cylindrical joint. |
no_velocity_ic | True_only | Specifies that if a VELOCITY_IC has been set via any means, to "UNSET" the velocity initial condition. |
friction_enabled | Enable_friction | |
delta_v | Real | |
maximum_deformation | Real | |
mu_dyn_trans | Real | |
mu_stat_trans | Real | |
max_fric_trans | Real | |
preload_x | Force | |
preload_y | Force | |
height | Real | Specify a height for the info window. |
width | Real | Specify a width for the info window. |
relative_to | An Existing Model, Part Or Marker | Specifies the coordinate system that location coordinates and orientation angles are with respect to. |
i_marker_name | An Existing Marker | Specifies a marker on the first of two parts connected by this joint. Adams View connects one part at the I marker to the other at the J marker. |
j_marker_name | An Existing Marker | Specifies a marker on the second of two parts connected by this joint. Adams View connects one part at the I marker to the other at the J marker. |
Extended Definition:
1. A translational joint is a single-degree-of-freedom joint that allows translational displacement of one part relative to another. For a translational joint, Adams keeps all the axes of the I and the J markers parallel and keeps the origin of the I marker on the z-axis of the J marker so that the two markers have a common z-axis. To determine the translational displacement of the I marker with respect to the J marker, Adams measures the origin of the I marker with respect to the origin of the J marker along their common z-axis.
2. You may identify a joint by typing its name or by picking it from the screen.
If the joint is not visible on the screen, you must type the name. You may also find it convenient to type the name even if the joint is displayed. If you created the joint by reading an Adams data set or graphics file, the joint name is the letters JOI followed by the Adams data set joint ID number. The name of Adams JOINT/101 is JOI101, for example. If you created the joint during preprocessing, you gave it a name at that time. If a joint is available by default, you may identify it by entering its name only. If it is not, you must enter its full name. To identify a joint under a model, for instance, you may need to enter the model name as well. For example, you may specify joint 'lower_pivot' in model 'links' by entering ".links.lower_pivot". You must separate multiple joint names by commas. If the joint is visible in one of your views, you may identify it by picking on any of the graphics associated with it. You need not separate multiple joint picks by commas.
3. For a translational joint, Adams keeps all the axes of the I and the J markers parallel and keeps the origin of the I marker on the z-axis of the J marker so that the two markers have a common z-axis. To determine the translational displacement of the I marker with respect to the J marker, Adams measures the origin of the I marker with respect to the origin of the J marker along their common z-axis.
4. Normally, entity names like the joint name are composed of alphabetic, numeric, or '_' (underscore) characters, and start with an alphabetic or '_' character. They may be any length. For more information, see
Using Extended Names. By enclosing the name in double quotes, you may use other printable characters, or start the name with a numeral. If a name contains characters, or starts with a numeral, you must always quote the name when entering it. Note that you can specify the parentage of an entity (e.g. what part "owns" a marker or a geometry element) when you CREATE it by changing the name. If you enter just the entity name, then the default parent will be assigned by Adams View. If you type in the full name, then you may over ride the default parent. In most cases, when creating an entity, Adams View will provide a default name. The default name that Adams View provides will specify the parentage that it has assumed. You may, or course, delete this name and use your own. The form of a full name is:
"...._NAME.GRAND_PARENT_NAME.PARENT_NAME.ENTITY_NAME"
The number of levels used varies from case to case and the parentage must exist before an entity can be assigned to it.
5. When you use the FILE ADAMS_DATA_SET WRITE command, Adams View writes an Adams data file for your model. Adams requires that each modeling element be identified by a unique integer identifier. If you use this parameter to specify a non-zero identifier, Adams View will use it in the corresponding statement in the Adams data file. You may also enter zero as an identifier, either explicitly or by default. The next time you write an Adams file, Adams View will replace the zero with a unique, internally-generated identifier. Adams View will permanently store this identifier with the element just as if you had entered it yourself. Normally, you would let all identifiers default to zero, and Adams View would generate the identifiers for you. You are never required to enter a non-zero identifier. You only need to specify it if, for some reason, you wish to control the Adams file output.
6. When an Adams Solver data file (.adm) is read into Adams View, all comments associated with a statement (from the end of the previous statement through the end of the current statement) are stored with the object. Comments in the data file can be associated with model. These comments must follow the title statement and be followed by the comment 'END OF MODEL COMMENTS'. This string must be uppercase. When an Adams Solver data file is written, the comments for an object are written before the statement corresponding to the object.
7. Adams View measures the translational displacement of the origin of the I marker along the common z-axis of the I and the J markers with respect to the origin of the J marker. If you specify TRANSLATIONAL_IC, but not VELOCITY_IC, Adams View will set VELOCITY_IC to zero. Joint initial conditions impose constraints that are active only during initial conditions analysis (not at the time of the initial configuration). Adams does not impose initial conditions during subsequent analyses. If you impose initial conditions on the joint that are inconsistent with those on a part in the joint, the initial conditions on the joint have precedence over those on the part. However, if you impose initial conditions on the joint that are inconsistent with imparted motions on the joint, the initial conditions as specified by the motion generator have precedence over those here.
8. Setting the no_translational_ic is not the same as setting the value to zero. A zero velocity is not the same as "no" velocity. Therefore, by setting this parameter to true there is no longer a velocity initial condition for this element.
9. Adams View measures the translational velocity of the origin of the I marker along the common z-axis of the I and the J markers with respect to the origin of the J marker. If you specify VELOCITY_IC, but not TRANSLATIONAL_IC, Adams View will set TRANSLATIONAL_IC to zero. Joint initial conditions impose constraints that are active only during initial conditions analysis (not at the time of the initial configuration). Adams does not impose initial conditions during subsequent analyses. If you impose initial conditions on the joint that are inconsistent with those on a part in the joint, the initial conditions on the joint have precedence over those n the part. However, if you impose initial conditions on the joint that are inconsistent with imparted motions on the joint, the initial conditions as specified by the motion generator have precedence over those here.
10. Setting the no_velocity_ic parameter is not the same as setting the value to zero. A zero velocity is not the same as "no" velocity. Therefore, by setting this parameter to true there is no longer a velocity initial condition for this element.
11. The height and the width values should be a real number between 0.0 and 2.0, where 2.0 represents the height of the Adams View window. Therefore, a value of 1.0 will set the info window to be one half as high as the Adams View window.
12. By default, you supply Cartesian (x, y, z) coordinates for the location parameter. You may use the 'defaults units coordinate_system_type =' command to change this convention. For example, selecting 'cylindrical' means you will subsequently be supplying r, theta, and z coordinates. Adams View applies your location coordinates in the coordinate system you identify with the RELATIVE_TO parameter. The default for the RELATIVE_TO parameter is the default coordinate system. (See the RELATIVE_TO parameter for this command).
13. Adams View will orient the coordinate system by starting from the initial coordinate system and applying three successive rotations. Depending on the convention you have selected, the rotations may occur about space-fixed or bodyfixed axes in any meaningful combination of the x, y, and z axes.
By default, you supply Euler (body313, or body-fixed z, x, z) angles. You may change this convention with the 'DEFAULTS UNITS ORIENTATION_TYPE=' command. For example, selecting SPACE123 means you will subsequently be supplying space-fixed x, y, and z angles. Adams View applies your orientation angles starting from the coordinate system you identify with the RELATIVE_TO parameter. The default for the RELATIVE_TO parameter is the default coordinate system.
14. For the along_axis_orientation parameter you may enter either one or two locations to direct the axis. If you enter one location, the axis will point toward the location. If you specify two locations, the axis will be parallel to, and pointing the same way as, the vector from the first location to the second. Note that this does not completely dictate the orientation of the coordinate system. Adams View will osition the coordinate system with an arbitrary rotation about the axis. If you must completely control the coordinate system orientation, use ORIENTATION or IN_PLANE_ORIENTATION. By default, you direct the Z axis of the coordinate system.
You may change this convention with the 'DEFAULTS ORIENT_AXIS_AND_PLANE AXIS_AND_PLANE_SETTING=' command. For example, selecting either X_AXIS_XY_PLANE or X_AXIS_XZ_PLANE means you will subsequently be directing the X axis. The plane-convention setting does not affect this parameter. Adams View applies your location coordinates in the coordinate system you identify with the RELATIVE_TO parameter. The default for the RELATIVE_TO parameter is the default coordinate system.
15. For the in_plane_orientation parameter you may enter either two or three locations. If you enter two locations, the axis will point toward the first location and the plane will fall on the second. If you specify three locations, the axis will be parallel to, and pointing the same way as, the vector from the first location to the second and the plane will be parallel to the plane defined by the three locations. By default, you direct the Z axis of the coordinate system and locate the ZX plane. You may use the 'DEFAULTS ORIENT_AXIS_AND_PLANE AXIS_AND_PLANE_SETTING=' command to change this convention. For example, selecting X_AXIS_XY_PLANE means you will subsequently be directing the X axis and locating the XY plane. Adams View applies your location coordinates in the coordinate system you identify with the RELATIVE_TO parameter. The default for the RELATIVE_TO parameter is the default coordinate system.
16. If the relative_to parameter is not specified, the default coordinate system is used. The default coordinate system is initially your model, i.e. the global coordinate system. You may change the default coordinate system using the 'defaults coordinate_system' command.
Tips:
1. If you type a "?", Adams View will list the joints available by default.