Wyniki wyszukiwania - BazTech

1

ABS system use impact on braking torque in aviation brake

Skorupka Z.

Journal of KONES

|

2014

|

Vol. 21, No. 1

259--265

EN

ABS (Anti-Locking) systems improve performance and safety of the braking systems. Use of ABS is now factory standard in both commercial and military aviation. ABS system in its origin was designed in order to prevent wheels from slipping and locking on the low friction surfaces such as ice. By preventing wheel, locking ABS system helps in not losing control over the vehicle during difficult braking conditions. In Aviation ABS, systems were introduced quite early as mechanical systems but their common usage is connected with computer and electronic systems development in 1970’s. In aircraft, ABS systems are responsible for safety of braking by preventing phenomena described above and for preventing landing with engaged brakes what is common in military and in big commercial aviation. In modern aviation ABS systems use is both safety and economical feature resulting in visible profits during airplane lifetime. Other question is efficiency of the process i.e. braking torque value. Braking torque is the most important parameter of brake from exploitation point of view. It is directly connected with braking distance as well with amount of force needed to achieve assumed braking parameters for the mechanical vehicle. Stability of braking torque is important in order to get optimized characteristics of the braking process itself. Most of the brake characteristics and efficiency calculations were based on assumption that braking torque should be stable during braking process. In this paper author would like to investigate ABS use impact on braking torque, which by definition is not stable in anti-lock equipped systems. Author will base on literature sources as well as on results of laboratory tests made during development of ABS system for 2700 kg take off mass airplane made in Landing Gear Laboratory of Warsaw Institute of Aviation in which author works on daily basis.

2

Braking moment comparison and analysis for various brake designs using results from sample and full scale friction material tests

Skorupka Z.

Journal of KONES

|

2013

|

Vol. 20, No. 1

303--308

EN

Brake is one of the most important safety feature in every mechanical vehicle from bikes to airplanes. Brakes have to be designed in order to meet safety, reliability, efficiency and economical requirements. One has to remember that not only design of brake is important but also friction material used in its construction. Without proper materials, brakes are not able to generate proper braking moment. Braking moment is the most important parameter of brake from operation point of view. It is directly connected to braking distance as well with amount of force needed to achieve assumed braking parameters for the mechanical vehicle. Stability of braking moment is important in order to get optimized characteristics of the braking process itself. Most of the brake characteristics and efficiency calculations base on assumption that braking moment should be stable during braking process. During years of tests made on full scale brakes and friction material sample tests, author observed that real braking moment curve is not stable during braking process. This phenomenon is likely to affect braking efficiency and in result slightly change braking distance. In this paper author would like to address this issue by showing brake moment curves made for different brakes and friction materials. Tests, which were author’s base for paper contents, were made using full scale brake testing and friction material sample testing. All of the tests described in the paper were performed in Landing Gear Laboratory of Warsaw Institute of Aviation in which author works on daily basis

3

Analysis Research of Control Method Model on Automobile Brake Test Rig

Yang C., Ren E., Dang J.

Przegląd Elektrotechniczny

|

2012

|

R. 88, nr 7b

375--378

EN

This paper, firstly in accordance with the engineering design method, PID controller are used to control the current loop and speed loop common on double closed-loop DC converter, and build dual-loop PID control model, and Matlab’s emulation to model, as well as analysis and evaluate the structural of the simulation. Because conventional PID control can not meet the parameters of the controlled object changes and lack of non-linear characteristics, the fuzzy self-tuning PID can overcome the uncertainty and nonlinear objects, furthermore the fuzzy self-tuning PID has more flexibility and adaptability, so this paper putting to use fuzzy self-tuning PID controller for dual-speed loop in the closed-loop system to transform, so that it has not or less affected by the object model, you can achieve high performance, robustness and other advantages.

PL

W artykule opisano metodę testowania system hamulcowego w pojazdach samochodowych. Ay uniezależnić wyniki testu od parametrów układu sterowania zaproponowano ulepszony kontroler PID z automatycznym strojeniem i wykorzystaniem logiki rozmytej.