Related Experiment Video
Updated: Dec 7, 2025
07:49
Development of an Experimental Setup for the Measurement of the Coefficient of Restitution under Vacuum Conditions
Published on: March 29, 2016
8.4K
Innovative Controllable Torsional Damper Based on Vacuum Packed Particles.
Dominik Rodak1, Robert Zalewski1
1Institute of Machines Design Fundamentals, Warsaw University of Technology, 02-254 Warsaw, Poland.
Materials (Basel, Switzerland)
|October 3, 2020
Summary
This study introduces a novel controllable granular damper using vacuum packed particles (VPPs). Adjusting the internal vacuum level allows for tunable damping properties, offering a new approach to vibration control.
Area of Science:
- Mechanical Engineering
- Materials Science
- Physics
Background:
- Granular materials offer unique mechanical properties.
- Controllable damping systems are crucial for vibration mitigation.
- Existing dampers often lack tunable characteristics.
Purpose of the Study:
- To present a new concept for a controllable granular damper.
- To investigate the mechanical behavior of vacuum packed particles (VPPs).
- To demonstrate tunable dissipative properties based on internal underpressure.
Main Methods:
- Development of a prototype damper utilizing vacuum packed particles (VPPs).
- Experimental testing to evaluate the damper's performance.
- Modification and application of the Bouc-Wen rheological model to describe hysteretic behavior.
Main Results:
- VPPs exhibit nonclassical solid-body behavior influenced by internal underpressure.
- The prototype damper shows controllable dissipative properties.
- The modified Bouc-Wen model accurately captures the damper's response.
Conclusions:
- The vacuum packed particle (VPP) concept provides a viable method for creating controllable granular dampers.
- Tunable mechanical properties are achievable by adjusting internal vacuum levels.
- The developed rheological model effectively characterizes the damper's hysteretic behavior.
More Related Videos
Related Concept Videos
01:17Magnetic Damping
873
Eddy currents can produce significant drag on motion, called magnetic damping. For instance, when a metallic pendulum bob swings between the poles of a strong magnet, significant drag acts on the bob as it enters and leaves the field, quickly damping the motion.
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
If, however, the bob is a slotted metal plate, the magnet produces a much smaller effect. When a slotted metal plate enters the field, an emf is induced by the change in flux; however, it is less effective because the slots limit the...
873
01:09Torsional Pendulum
6.7K
A torsional pendulum involves the oscillation of a rigid body in which the restoring force is provided by the torsion in the string from which the rigid body is suspended. Ideally, the string should be massless; practically, its mass is much smaller than the rigid body's mass and is neglected.
As long as the rigid body's angular displacement is small, its oscillation can be modeled as a linear angular oscillation. The amplitude of the oscillation is an angle. The role of mass is played...
As long as the rigid body's angular displacement is small, its oscillation can be modeled as a linear angular oscillation. The amplitude of the oscillation is an angle. The role of mass is played...
6.7K
01:20Types of Damping
7.3K
If the amount of damping in a system is gradually increased, the period and frequency start to become affected because damping opposes, and hence slows, the back and forth motion (the net force is smaller in both directions). If there is a very large amount of damping, the system does not even oscillate; instead, it slowly moves toward equilibrium. In brief, an overdamped system moves slowly towards equilibrium, whereas an underdamped system moves quickly to equilibrium but will oscillate about...
7.3K
01:07Damped Oscillations
6.6K
In the real world, oscillations seldom follow true simple harmonic motion. A system that continues its motion indefinitely without losing its amplitude is termed undamped. However, friction of some sort usually dampens the motion, so it fades away or needs more force to continue. For example, a guitar string stops oscillating a few seconds after being plucked. Similarly, one must continually push a swing to keep a child swinging on a playground.
Although friction and other non-conservative...
Although friction and other non-conservative...
6.6K
01:20Bending and Torsional Moments
5.1K
Bending and torsional moments are two fundamental concepts in structural engineering. They play an important role in understanding the behavior of materials and structures under different loading conditions.
The reaction developed in a structural element when subjected to an external force causes the element to bend. When a structural element bends upwards, it creates compressive normal forces on the top and tensile normal forces on the bottom, resulting in a couple that determines the bending...
The reaction developed in a structural element when subjected to an external force causes the element to bend. When a structural element bends upwards, it creates compressive normal forces on the top and tensile normal forces on the bottom, resulting in a couple that determines the bending...
5.1K
01:22Mechanical Systems
460
Mechanical systems are analogous to to electrical networks where springs and masses play similar roles to inductors and capacitors, respectively. A viscous damper in mechanical systems functions similarly to a resistor in electrical networks, dissipating energy. The forces acting on a mass in such systems include an applied force in the direction of motion, counteracted by forces from the spring, a viscous damper, and the mass's acceleration. This interplay of forces is mathematically...
460