Pracownicy

Streszczenie:
This study explores numerically and experimentally innovative control strategies for self-adaptive shock absorbers designed to operate under varying impact conditions. The control problem is addressed with a fundamental constraint – a limited prior knowledge of excitation parameters. To tackle this challenge, state-dependent control methods with progressively enhanced adaptive capabilities are proposed and evaluated numerically. A dedicated experimental setup featuring a pneumatic adaptive shock absorber is developed to ensure validation of the proposed methods and facilitate their comparison. The system incorporates a fast-operating piezoelectric valve with a strain gauge for proportional opening control and enables optimal real-time response to unknown dynamic excitations. The conducted laboratory drop test results confirm the feasibility of the proposed control methods.

Słowa kluczowe:
Adaptive Impact Absorption, Self-Adaptive System, Pneumatic Shock Absorber

Streszczenie:
The work presents a comprehensive approach to the design and modelling of acoustic materials based on labyrinth structures filled with fibres. It has recently been shown that exceptionally favourable acoustic properties can be obtained in labyrinthine materials due to their extreme tortuosity. Such materials, typically produced by methods such as 3D printing, exhibit high sound absorption values at lower frequencies. The next step in the development of this type of acoustic treatment (explored here) involves introducing fibres into labyrinthine channels. Such acoustic composite designs can have a beneficial effect of shifting the absorption peak to even lower frequencies and also widening its efficiency range. Two samples of slotted labyrinth materials, designed using analytical acoustic modelling, were 3D printed, and their slits were filled with selected fibrous materials, such as biofibres, cotton wool, acrylic yarn, etc. They were tested in an impedance tube to confirm the predicted improvement, but also to show a dramatic change in sound absorption.

Słowa kluczowe:
Air-drop Capsule, Impact Mitigation, Adaptable Airbag, Discharge Valve