Create panel > Geometry > Dynamics Objects > Object Type rollout > Damper button
Create menu > Dynamics > Damper
The Damper object provides a dynamic object that can behave as either a shock-absorber or an actuator. It consists of a base, a main housing, and a piston, with an optional boot. The piston slides within the main housing, providing different heights. The overall height can be affected by binding objects, in the same way as the Spring dynamic object.
Note: Damper is similar to Spring in many respects. See Spring object for more detailed descriptions of similar parameters and procedures.
To use a damper in a dynamics simulation:
The following must be in place to use the damper forces in a dynamics simulation:
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Bind two objects to the ends of the damper, and choose Bound to Object Pivots in the End Point Method group box at the top of the command panel.
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In the dynamics simulation, add the damper to the Object List. (The damper itself is not adjusted in the dynamics simulation, so all of the dynamics parameters will be disabled for the damper object.)
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Include at least one of the bound objects or a parent of one of the bound objects in the simulation. For example, you can bind two dummy objects to the ends of a damper, and one of the dummies can be the child of an object that’s included in the simulation. In this case, the dummy itself does not need to be in the simulation.
Note: Damper is an "ideal" object with no mass. While it can be used in dynamics simulations, it cannot participate directly in collisions or effects. As a result, when you assign a damper object to a dynamics simulation, and then view it in the Edit Object dialog, all of the parameter settings are disabled.
Free Damper/Actuator—Choose this when using the damper as a simple object that’s not bound to others or used in a dynamics simulation.
Bound to Object Pivots—Choose this option when binding the damper to two objects, using the buttons described next.
Use these controls to pick the objects to which the damper is bound. To complete the binding, you must select two binding objects, and then click Bound to Object Pivots.
Piston (label)—Displays the name of the object bound to the piston of the damper.
Pick Piston Object—Click this button and then select the object to be bound to the piston of the damper.
Base (label)—Displays the name of the object bound to the base of the damper.
Pick Base Object—Click this button and then select the object to be bound to the base of the damper.
Pin-to-Pin Height—Use this field/spinner to specify the distance between the bottom center of the base and the top center of the piston when the damper is not bound.
Renderable—When on, the object appears in the rendering; when off, the object does not appear.
Material IDs are assigned to the damper object as follows:
4: Boot Stop (appears only if you enable Boot Parameters)
5: Boot (appears only if you enable Boot Parameters)
Generate Mapping Coords—Sets up the required coordinates for applying mapped materials to the object. Default=on.
Provides parameters for the base and main cylinder of the damper.
Base Dia—The diameter of the base, or "mount" of the damper.
Height—The height of the base.
Main Dia—The diameter of the main housing of the damper.
Height—The height of the main housing.
Sides—The number of sides of both the base and the main housing.
Fillet 1—The size of the fillet on the lower edge of the main housing.
Fillet Segs—The number of segments for Fillet 1. The higher this setting, the rounder the fillet profile appears.
Fillet 2—The size of the fillet on the upper edge of the main housing.
Fillet Segs—The number of segments for Fillet 2. The higher this setting, the rounder the fillet profile appears.
Inside Dia—Specifies the inside diameter of the main housing, which is actually a tube rather than a cylinder.
Smooth Cylinder—When on, smoothing is applied to both the base and the main housing.
Provides parameters for the piston of the damper.
Diameter—The diameter of the piston.
Height—The height of the piston.
The boot is an optional component of the damper that’s similar to the rubber "accordion" boot found on various types of dampers, such as shock absorbers. The boot acts like a bound dynamic object, in that one of its ends is bound to the main housing, while the other is bound to the piston. Thus, as the piston moves within the housing, the boot expands and contracts to follow.
Enable—Turn this on to add the boot to the damper.
Min Dia—The minimum diameter of the boot. This and the next parameter affect the depth of the accordion folds in the boot.
Max Dia—The maximum diameter of the boot.
Sides—The number of sides making up the boot.
Folds—The number of accordion folds (bulges) along the height of the boot.
Resolution—The number of segments in each fold.
Stop Dia—The diameter of the stop, which is the ring at the top of the boot.
Stop Thick—The thickness (height) of the stop ring.
Setback—The distance of the stop ring from the top of the piston.
Stop Fillet—The size of the fillet on the upper edge of the stop ring.
Fillet Segs—The number of segments the stop fillet. The higher this setting, the round the fillet profile appears.
Unlike the Spring object, the damper can also be used as an actuator. Basically, a damper absorbs force (like a shock absorber) while an actuator applies force.
The parameters in this group box, available only when End Point Method is set to Bound to Object Pivots, specify how forces are applied by the damper object in a dynamics simulation.
Damper Parameters—Provides parameters for a damper type of object. Specifically, this simulates a viscous linear damper, which provides linear resistance to motion (between the two binding objects) proportional to the rate at which the damper experiences displacement. The faster it gets hit, the harder it fights back. Push it slowly, and there’s almost no resistance.
Drag—Specifies the force per unit linear speed, measured in one of the methods specified below.
Compression Only—The damper reacts only to compression forces.
Extension Only—The damper reacts only to expansion forces.
Both—The damper reacts to both compression and expansion forces.
Actuator Parameters—Provides parameters for an actuator. When used as an actuator, the damper object exerts force between the two binding objects. A real-world example might be the thrusting piston in a log splitter. When used in a simulation, the force is applied by adjusting the value in the Force spinner. You can see the result only after solving the dynamics simulation.
Force—Specifies the amount of force exerted between the two bound objects. Positive values push the objects apart, while negative values pull them together.