scholarly journals THEORETICAL-EXPERIMENTAL ASSESMENT OF BRAKING SISTEMS FOR INCLINED LIFTS ACCORDING TO EN 81:22-2014.

2016 ◽  
Author(s):  
Enrique Alcalá ◽  
Beatriz Valles Fernandez ◽  
Angel Luis Martin López
Keyword(s):  
Simulation Model ◽  
Relative Displacement ◽  
Dynamical Behaviour ◽  
Emergency Braking ◽  
Braking System ◽  
Calculation Methodology ◽  
Norm Series ◽  
Definition Of ◽  
Optimal Behaviour

The inclined lifts, in case of emergency braking, can experience high longitudinal decelerations that can lead to passengers’ collisions with lift walls and interior elements. In 2014 the CEN/TC10 WG1 published the part 22 of the norm series 81 with regard to the construction elements and installation of electrical lifts with inclined trajectory. This norm stablishes, amongst other requirements, the maximum and minimum deceleration levels in both longitudinal and vertical directions. Both requirements, in opposite senses and the definition of the braking system, do not cause design difficulties in case of high slopes, but in case of lifts with the slope under a certain level they can be needed, to guarantee the fulfilment of the norm, elements that allow and additional relative displacement between the braking system and the cabin. To define the performances and the optimal behaviour of these systems it has been defined a simulation model of the dynamical behaviour of the lift under the conditions of the norm tests. Additionally, in this work it is presented a calculation methodology to define the cabin allowable weight corridor, for each braking effort made by each safety gear model, and the simulations have been validated with the results of tests with different braking efforts, weights and lift slopes. The present work has been performed in cooperation with Thyssen Krupp Elevadores with the aim of improving the knowledge of the brake dynamics of inclined lifts.DOI: http://dx.doi.org/10.4995/CIT2016.2016.2173

scholarly journals FEATURES OF ADAPTIVE BRAKE CONTROL OF THE SECONDARY BRAKE SYSTEM OF A MULTI-AXLE VEHICLE

2021 ◽  
pp. 27-37
Author(s):  
Viktor Bogomolov ◽  
Valeriy Klimenko ◽  
Dmytro Leontiev ◽  
Oleksandr Kuripka ◽  
Andrii Frolov ◽  
...  
Keyword(s):  
Simulation Model ◽  
Road Safety ◽  
Road Surface ◽  
Brake System ◽  
Technical Literature ◽  
Adhesion Properties ◽  
The Road ◽  
Emergency Braking ◽  
Braking System ◽  
Braking Process

Problem. A malfunction of the service braking system of a wheeled vehicle (CTS) significantly affects road safety, especially when operating multi-axle vehicles with large masses. One of the ways to increase the level of road safety of multi-axle vehicles, when braking them using a spare (emergency) braking system, is the introduction of automated adaptive braking systems into the design of the brake drive of vehicles. The definition of the limits of the use of the adaptive braking system on vehicles with many axles is almost not disclosed in the scientific and technical literature, therefore, the issue of using such a system on vehicles with a large number of axles requires additional research. Purpose. The purpose of this work is to develop a simulation model for adaptive control of the braking process of a multi-axle vehicle using a spare (emergency) braking system, taking into account the simulation of the dynamics of the drive and the variability of the adhesion properties between the tire of the vehicle wheel and the road surface. Methodology. To achieve this goal, it is necessary to develop a simulation model of the brake drive in an adaptive mode, implement a model of the interaction of the tire with the road surface, and implement a model of the braking dynamics of a multi-axle vehicle in the event of a malfunction of its service brake system. Originality. The proposed key criterion (Kr) for changing the throttle section in electro-pneumatic pressure modulators, which provide adaptive air inlet or outlet from the corresponding brake chambers of the drive, during simulation, made it possible to simulate the operation of the drive circuits in the adaptive mode. It has been established that, depending on the potential for the realization of the adhesion between the tires of automobile wheels and the road surface, the pressure in the electro-pneumatic brake drive with its adaptive regulation can be increased by no more than 0.04 MPa.

Co-simulation model coupling of flexible rope hoisting system and hydraulic braking system for a mine hoist

2021 ◽  
pp. 095440892110535
Author(s):  
Song Ziyu ◽  
Wang Xiaona ◽  
Li Yajing ◽  
Guo Yu ◽  
Hao Huimin ◽  
...  
Keyword(s):  
Simulation Model ◽  
Coupling Effect ◽  
Steel Wire ◽  
Joint Modeling ◽  
System Model ◽  
Emergency Braking ◽  
Braking System ◽  
Hydraulic Brake ◽  
Hoisting System ◽  
Mine Hoist

The hoist is an important equipment in the mine pit. Since the containers are lifted or lowered with flexible steel wire ropes, there are shocks and vibrations during operation, especially in the emergency braking stage, the shocks and vibration will be more severe. Mine hoist is a complex system; therefore, it is difficult to obtain all its dynamics information only by investigating the flexible hoisting subsystem or hydraulic brake subsystem. Therefore, it is very necessary to establish an accurate model to predict these characteristics of the hoist, this will provide useful tools for hoist design and maintenance. Therefore, a joint modeling methodology is proposed and implemented in this paper. A hoisting system model considering the non-linear factors such as contact characteristics and flexibility was established in RecurDyn. The hydraulic braking system model and control system model were established in AMESim, and the co-simulation model was constructed by the interface module. In this co-simulation model, not only the flexible hoisting subsystem and hydraulic brake subsystem are included, but also the coupling effect of subsystems is considered. Finally, taking the lifting condition as an example, execute emergency braking research on the hoisting system under experiment, mathematical model, and co-simulation model, respectively. Comparing the co-simulation model with the mathematical dynamics model, and the experimental test results, research indicates that the joint simulation model of coupled hoisting system and hydraulic braking system can effectively reflect the dynamic characteristics of the actual hoisting system. It provides an effective tool for hoist design, optimization, performance analysis, and operating condition simulation. In addition, the methods and techniques used in the co-simulation modeling procedure are portable. Therefore, the paper is of significance for the mine hoist.

Pressure Coordinated Control System of Regenerative Braking Based on Hardware of ABS for HEV

2011 ◽  
Vol 121-126 ◽  
pp. 3406-3410 ◽  
Author(s):  
Yang Yang ◽  
Yang Yang ◽  
Da Tong Qin ◽  
Jin Li
Keyword(s):  
Control System ◽  
Simulation Model ◽  
Electric Vehicles ◽  
Hybrid Electric Vehicles ◽  
Coordinated Control ◽  
Regenerative Braking ◽  
Design And Optimization ◽  
Braking System ◽  
Dynamic Performances ◽  
Simulation Results

A new kind of pressure coordinated control system suite of regenerative braking system for hybrid electric vehicles (HEV) is proposed in this paper on the basis of appropriate transformation on traditional hydraulic braking system with ABS. AMEsim modular simulation platform is used to build a simulation model of the system. Dynamic performances of the key components and system are simulated and analyzed. And the simulation results show the effectiveness and feasibility of the pressure coordinated control system, which lays the foundation of the design and optimization for the regenerative braking system.

scholarly journals Simulation Study of the Process of Friction in the Working Elements of a Car Braking System at Different Degrees of Wear

2018 ◽  
Vol 12 (3) ◽  
pp. 221-226 ◽  
Author(s):  
Andrzej Borawski
Keyword(s):  
Simulation Study ◽  
Friction Pair ◽  
Experimental Studies ◽  
Real Life ◽  
Operating Conditions ◽  
Heating Process ◽  
Passenger Cars ◽  
The Road ◽  
Emergency Braking ◽  
Braking System

Abstract Among the many elements of a modern vehicle, the braking system is definitely among the most important ones. Health, and, frequently, life, may rest upon the design and reliability of brakes. The most common friction pair used in passenger cars today is a disc which rotates with the road wheel and a cooperating pair of brake pads. The composite material of the pad results in changing tribological properties as the pad wears, which was demonstrated in experimental studies. The change is also facilitated by the harsh operating conditions of brakes (high and rapid temperature changes, water, etc.). This paper looks into how changing tribology reflects on the heating process of disc and pads during braking. And so a simulation study was conducted, as this method makes it possible to measure temperature in any given point and at any time, which is either impossible or extremely difficult in real life conditions. Finite element method analyses were performed for emergency braking events at various initial speeds of the vehicle reflecting the current road speed limits.

scholarly journals Development and Testing of a Collision Avoidance Braking System for an Autonomous Vehicle

2019 ◽  
Vol 8 (12) ◽  
pp. 703-709
Keyword(s):  
Autonomous Vehicle ◽  
Test Results ◽  
Correct Operation ◽  
Braking Performance ◽  
System Parameters ◽  
Emergency Braking ◽  
Braking System ◽  
Good Consistency ◽  
Main Development ◽  
Outdoor Experiments

The article describes the main development and testing aspects of an emergency braking function for an autonomous vehicle. The purpose of this function is to prevent the vehicle from collisions with obstacles, either stationary or moving. An algorithm is proposed to calculate deceleration for the automated braking, which takes into account the distance to the obstacle and velocities of both the vehicle and the obstacle. In addition, the algorithm adapts to deviations from the required deceleration, which are inevitable in the real-world practice due to external and internal disturbances and unaccounted dynamics of the vehicle and its systems. The algorithm was implemented as a part of the vehicle’s mathematical model. Simulations were conducted, which allowed to verify algorithm’s operability and tentatively select the system parameters providing satisfactory braking performance of the vehicle. The braking function elaborated by means of modeling then was connected to the solenoid braking controller of the experimental autonomous vehicle using a real-time prototyping technology. In order to estimate operability and calibrate parameters of the function, outdoor experiments were conducted at a test track. A good consistency was observed between the test results and simulation results. The test results have proven correct operation of the emergency braking function, acceptable braking performance of the vehicle provided by this function, and its capability of preventing collisions.

Sign in / Sign up

Export Citation Format

Share Document