Translational spring-damper system
The block represents a spring-damper system commonly used to dampen vibration in mechanical systems. An internal force acts between ports R and C. This force is the sum of spring stiffness, damping, Coulomb friction, and hard-stop contributions. All force contributions are optional. The net internal force satisfies the expression
F — Net internal force
Fspr — Spring force,
Fd — Damping force,
Fc — Coulomb friction force,
FHS — Hard stop force,
k — Restoring spring stiffness
b — Viscous damping coefficient
x — Relative displacement between ports R and C
v — Relative velocity between R and C
Fk — Kinetic friction force
Fs — Static friction force
kHS — Hard stop contact stiffness coefficient
kHS — Hard stop damping coefficient
UB — Hard stop upper bound
LB — Hard stop lower bound
The shock absorber block is based on the blocks listed in the table. For more information, see the corresponding block reference pages.
|Loaded-Contact Translational Friction||SimDriveline Brakes & Detents/Translational|
|Translational Spring||Simscape Foundation Library/Mechanical/Translational|
|Translational Hard Stop|
The use of hard-stop and Coulomb friction enhances model fidelity, but reduces simulation speed. See Improve Performance in the product documentation.
Enter the value of the viscous spring stiffness constant, k. The value must be greater than or equal to zero.
The default value is 1e+4. the default unit is N/m.
Enter the value of the viscous damping constant, b. The value must be greater than or equal to zero.
The default value is 100. The default unit is m/s.
Enter the value of the Coulomb friction force. The value must be greater than or equal to zero. Setting the value to 0 eliminates the Coulomb friction force contribution. This enhances simulation speed, making the model more suitable for HIL testing.
The default value is 0. The default unit is N.
Enter the value of the static/kinetic friction ratio (Fs/Fk). The value must be greater than one.
The default value is 1.1.
Enter the value of the relative velocity below which ports R and C lock and translate together. The value must greater than zero.
The default value is 0.001. The default unit is m/s.
Select hard stop model. Selecting No hard-stops — Suitable for HIL simulation eliminates the hard stop force contribution. This enhances simulation speed.
The default setting is No hard stops — Suitable for HIL simulation.