part modify external_system initial velocity
Allows the modification of initial velocities on an existing external system part.
You can specify initial velocities for parts. Adams View uses the initial velocity during the initial conditions simulation, which it runs before it runs a simulation of your model.
You can specify translational and angular velocities for rigid bodies and only translational velocity for point masses.
■Translational velocity defines the time rate of change of a part's center of mass with respect to ground or another marker in your model. You can specify translational velocity for each vector component of the marker.
■Angular velocity defines the time rate of change of a part's rotational position with respect to the CM marker of the part or another marker in your model. You can specify angular velocity for each vector component of the marker.
If you specify initial velocities, Adams View uses them as the initial velocity of the part during assemble model operations, regardless of any other forces acting on the part. You can also leave some or all of the velocities unset. Leaving a velocity unset lets Adams View calculate the velocity of the part during an assemble operation depending on the other forces and constraints acting on the part. Note that it is not the same as setting the initial velocity to zero. Setting an initial velocity to zero means that the part will not be moving in the specified direction when the simulation starts, regardless of any forces and constraints acting upon it.
Translational velocities are specified by parameters VX, VY, and VZ. Rotational velocities are specified by parameters WX, WY, and WZ. Note that the initial translational velocities are with respect to the ground coordinate axes, while the initial rotational velocities are with respect to the center-of-mass marker axes.
Format:
part modify external_system initial_velocity |
|---|
external_system_name = | an existing external system part |
vm = | existing marker |
wm = | existing marker |
vx = | velocity |
no_vx = | true_only |
vy = | velocity |
no_vy = | true_only |
vz = | velocity |
no_vz = | true_only |
wx = | angular_vel |
no_wx = | true_only |
wy = | angular_vel |
no_wy = | true_only |
wz = | angular_vel |
no_wz = | true_only |
Example:
part modify external_system initial_velocity & |
|---|
external_system_name = | external_system_2 & |
vm = | cm & |
wm = | cm & |
vx = | 4 & |
no_vy = | true & |
no_vz = | true & |
no_wz = | true & |
no_wy = | true & |
no_wz = | true |
Parameter | Value Type | Description |
|---|
external_system_name | Existing external system part | Specifies the external system to be modified |
vm | Existing marker | Specifies the marker representing the translational velocity |
wm | Existing marker | Specifies the marker representing the rotational velocity about it |
vx | Velocity | Specifies the translation velocity in x of vm |
no_vx | True_only | Specifies the zero translational velocity in x of vm |
vy | Velocity | Specifies the translation velocity in y of vm |
no_vy | True_only | Specifies the zero translational velocity in y of vm |
vz | Velocity | Specifies the translation velocity in z of vm |
no_vz | True_only | Specifies the zero translational velocity in z of vm |
wx | Angular_velocity | Specifies the rotational velocity about x of wm |
no_wx | True_only | Specifies the zero rotational velocity about x of wm |
wy | Angular_velocity | Specifies the rotational velocity about y of wm |
no_wy | True_only | Specifies the zero rotational velocity about y of wm |
wz | Angular_velocity | Specifies the rotational velocity about z of wm |
no_wz | True_only | Specifies the zero rotational velocity about z of wm |
Extended Definition:
1. The external_system_name specifies the external system part to be modified. You use this parameter to identify the existing part to be affected with this command. You may identify a part by typing its name or by picking it from the screen. If the part is not visible on the screen, you must type the name. You may also find it convenient to type the name even if the part is displayed.If you created the part by reading an Adams data set or graphics file, the part name is the letters PAR followed by the Adams data set part ID number. The name of Adams PART/101 is PAR101, for example. If you created the part during preprocessing, you would have given it a name at that time. If a part is available by default, you may identify it by entering only its name. If it is not, you must enter its full name. To identify a part under another model, for instance, you may need to enter the model name as well. For example, you may specify part 'arm' from model 'robot' by entering ".robot.arm". If you type a "?", Adams View will list the parts available by default. You must separate multiple part names by commas. If the part 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 part picks by commas.
2. The vm specifies the marker with reference to which the x, y, z components of velocities of the 'PART', vx, vy, vz respectively are specified. Translational velocity defines the time rate of change of a part's center of mass with respect to ground or another marker 'vm' in your model. You can specify translational velocity for each vector component of the marker as vx, vy and vz.
3. If the part has no translational velocity in either x, y or z directions, then you need not specify it explicitly. By default, the initial velocity is zero. Or else, you can set it to zero by setting parameters 'no_vx', 'no_vy', and 'no_vz' to TRUE.
4. The wm specifies the marker about which the rotational velocities of the part are specified. The wx, wy, wz components are the rotational velocities of the part about x, y, and z axis of the marker 'wm', respectively. Angular velocity defines the time rate of change of a part's rotational position with respect to the CM marker of the part or another marker 'wm' in your model. You can specify angular velocity for each vector component of the marker as wx, wy, wz.
5. If the part has no rotational velocity about either x, y or z directions of 'wm' marker, then you need not specify it explicitly. By default, the initial rotational velocity is zero. Or else, you can set it to zero by setting parameters 'no_wx', 'no_wy', and 'no_wz' to TRUE.