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constraint create joint translational
Allows the creation of a translational joint. A translational joint is a single-degree-of-freedom joint that allows translational displacement of one part relative to another.
Format:
constraint create joint translational joint_name = a new joint
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
i_part_name = an existing body j_part_name = an existing body
location = location orientation = location along_axis_orientation = location in_plane_orientation = location
relative_to = an existing model, part or marker i_marker_name = an existing marker
j_marker_name = an existing marker
Example:
Description:
constraint create joint translational &
joint_name = joint__1 &
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
Parameter Value Type Description
joint_name A New Joint Specifies the name of the 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.
Adams/View Commands constraint create joint translational 78
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.
height Real Specify a height for the info window.
width Real Specify a width for the info window.
i_part_name An Existing Body Specifies the part that is the first of two parts connected by this joint.
j_part_name An Existing Body Specifies the part that is the second of two parts connected by this joint.
location Location Specifies the locations to be used to define the position of a constraint during its creation.
orientation Orientation Specifies the orientation of the J marker for the constraint being created using three rotation angles.
along_axis_orientation Location Specifies the orientation of a coordinate system (e.g.
marker or part) by directing one of the axes.
Adams/View will assign an arbitrary rotation about the axis.
in_plane_orientation Location Specifies the orientation of a coordinate system (e.g.
marker or part) by directing one of the axes and locating one of the coordinate planes.
Parameter Value Type Description
Extended Definition:
1. 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 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. 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. 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.
3. 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.
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.
j_marker_name An Existing Marker Specifies a marker on the second of two parts connected by this joint.
Parameter Value Type Description
Adams/View Commands constraint create joint translational 80
4. 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.
5. 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.
6. 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.
7. 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.
8. 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.
9. 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.
10. 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).
11. 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.
12. 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.
13. 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.
14. 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.
Adams/View Commands constraint create joint translational 82
Tip: 1. You may use the joint_name later to refer to this joint. Adams/View will not allow you to have two joints with the same full name, so you must provide a unique name.
2. Adams/View connects one part at the I marker to the other at the J marker. These markers are automatically generated using this method of joint creation.
3. The I and J markers will be automatically created at this location on the I_PART_NAME and J_PART_NAME respectively.
4. The I marker is oriented based on the J marker orientation and the requirements of the particular constraint being created. These markers are created automatically.