scholarly journals Pressure Estimation Based on Vehicle Dynamics Considering the Evolution of the Brake Linings’ Coefficient of Friction

Actuators ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 76
Author(s):  
Biaofei Shi ◽  
Lu Xiong ◽  
Zhuoping Yu
Keyword(s):  
Coefficient Of Friction ◽  
Measurement Unit ◽  
Vehicle Speed ◽  
Test Results ◽  
Brake Pressure ◽  
Slope Change ◽  
Pressure Estimation ◽  
Vehicle Test ◽  
Vehicle Information ◽  
Road Slope

To mitigate the issue of low accuracy and poor robustness of the master cylinder pressure estimation (MCPE) of the electro-hydraulic brake system (EHB) by adopting EHB’s own information, a MCPE algorithm based on vehicle information considering the evolution of the brake linings’ coefficient of friction (BLCF) is proposed. First, the MCPE algorithm was derived combining the vehicle longitudinal dynamics and the wheel dynamics, in which the inertial measurement unit (IMU) was adopted to adapt the MCPE algorithm to road slope change. In order to estimate the brake pressure accurately, the driving resistance of the vehicle was obtained through a vehicle test under coasting condition. After that, with the active braking function of EHB, the evolution of the BLCF was acquired through extensive real vehicle test under different initial temperatures, different initial vehicle speeds, and different brake pressures. According to the test results, a revised model of the BLCF is proposed. Finally, the performance of the MCPE based on the revised BLCF model was compared with that based on a fixed BLCF model. Vehicle test demonstrates that the former MCPE algorithm is not only more accurate at low vehicle speed than the later, but also robust to road slope change.

In-Vehicle Test Results for Advanced Propulsion and Vehicle System Controls Using Connected and Automated Vehicle Information

2021 ◽  
Author(s):  
Shreshta Rajakumar Deshpande ◽  
Shobhit Gupta ◽  
Dennis Kibalama ◽  
Nicola Pivaro ◽  
Marcello Canova ◽  
...  
Keyword(s):  
Test Results ◽  
Automated Vehicle ◽  
Vehicle System ◽  
Vehicle Test ◽  
Vehicle Information

scholarly journals Integrated GNSS/IMU-Gyrocompass with Rotating IMU. Development and Test Results

2020 ◽  
Vol 12 (22) ◽  
pp. 3736
Author(s):  
Gennadiy Emel’yantsev ◽  
Oleg Stepanov ◽  
Aleksey Stepanov ◽  
Boris Blazhnov ◽  
Elena Dranitsyna ◽  
...  
Keyword(s):  
Inertial Measurement Unit ◽  
Fiber Optic ◽  
Measurement Unit ◽  
Prototype Model ◽  
Navigation Satellite ◽  
Test Results ◽  
Rotating Platform ◽  
Inertial Measurement ◽  
Urban Conditions ◽  
The Given

The paper presents the developed integrated GNSS/IMU gyrocompass which, unlike the existing systems, contains a single-axis rotating platform with two antennas installed on it and an inertial measurement unit with tactical grade fiber-optic gyros. It is shown that the proposed design provides attitude solution by observing the signals of only one navigation satellite. The structure of the integrated GNSS/IMU gyrocompass, its specific features and prototype model used in the tests are described. The given test results in urban conditions confirmed heading determination accurate to ±1.5° (3σ).

Friction-Instability: A New Design Parameter for Brakes

1971 ◽  
Vol 93 (4) ◽  
pp. 1225-1228 ◽  
Author(s):  
W. L. Starkey ◽  
T. G. Foster ◽  
S. M. Marco
Keyword(s):  
Quality Control ◽  
Coefficient Of Friction ◽  
Design Parameter ◽  
Control Device ◽  
Experimental Facility ◽  
Test Results ◽  
Effective Manner ◽  
The Coefficient Of Friction ◽  
Brake Lining ◽  
The Right

A new design parameter, friction-instability, is defined in this paper. Friction-instability is a variation in the coefficient of friction which may occur at any time during the life of a brake lining. A friction-index is defined which measures this variation. A lining which has a high friction index may tend to cause an automobile to swerve either to the right or to the left. A unique experimental facility is described by means of which the friction-instability characteristics of brake linings can be measured. Test results using this facility are presented and interpreted. The friction-index is proposed as a new parameter which should be taken into consideration when brakes are designed and, developed. This index should be particularly useful as a quality control device to insure that machines which use mass-produced braking systems will perform in a safe and effective manner.

Calculation of Cylindrical Worm Gear Drives of Different Tooth Profiles

1981 ◽  
Vol 103 (1) ◽  
pp. 73-82 ◽  
Author(s):  
H. Winter ◽  
H. Wilkesmann
Keyword(s):  
Coefficient Of Friction ◽  
Theoretical Basis ◽  
Power Loss ◽  
Influence Factor ◽  
Load Capacity ◽  
Worm Gear ◽  
Important Influence ◽  
Test Results ◽  
The Coefficient Of Friction ◽  
Gear Drives

The formulae of classical hydrodynamics are not suitable for the calculation of load capacity and power loss of worm gear drives. Thus a theoretical basis had to be developed for the comparison of different tooth profiles, materials of worm and worm wheel and lubricants. The data obtained were compared with test results. It proved that the coefficient of friction is an important influence factor.

scholarly journals An Overview of Heavy Trucks/Buses Braking Performance

1991 ◽  
Vol 8 (1) ◽  
Author(s):  
Richard M. Ziernicki
Keyword(s):  
Statistical Data ◽  
Vehicle Speed ◽  
Test Results ◽  
Heavy Duty ◽  
Braking Performance ◽  
Emergency Braking ◽  
Heavy Trucks ◽  
Brake Performance ◽  
Drag Factor ◽  
Heavy Duty Vehicles

The writer discusses the performance of heavy duty vehicles during emergency braking. The paper reviews statistical data related to the trucking accidents, and discusses brake performance, tires, and the stopping ability of heavy duty vehicles. Relationships between drag factor, coefficient of friction, vehicle speed, type of tire, road surface, brake design, and brake temperature are discussed. Some of the test results performed on heavy trucks are presented. The discussion is general in order to make the presentation useful both to practicing reconstruction specialists, and to attorneys.

scholarly journals Research on Lane a Compensation Method Based on Multi-Sensor Fusion

Sensors ◽  
2019 ◽  
Vol 19 (7) ◽  
pp. 1584 ◽  
Author(s):  
Yushan Li ◽  
Wenbo Zhang ◽  
Xuewu Ji ◽  
Chuanxiang Ren ◽  
Jian Wu
Keyword(s):  
Real Time ◽  
Sensor Fusion ◽  
Compensation Method ◽  
Measurement Unit ◽  
Vision Sensor ◽  
Vision Sensors ◽  
Cubic Polynomial ◽  
Vehicle Test ◽  
Yaw Angle ◽  
Geometric Relationship

The curvature of the lane output by the vision sensor caused by shadows, changes in lighting and line breaking jumps over in a period of time, which leads to serious problems for unmanned driving control. It is particularly important to predict or compensate the real lane in real-time during sensor jumps. This paper presents a lane compensation method based on multi-sensor fusion of global positioning system (GPS), inertial measurement unit (IMU) and vision sensors. In order to compensate the lane, the cubic polynomial function of the longitudinal distance is selected as the lane model. In this method, a Kalman filter is used to estimate vehicle velocity and yaw angle by GPS and IMU measurements, and a vehicle kinematics model is established to describe vehicle motion. It uses the geometric relationship between vehicle and relative lane motion at the current moment to solve the coefficient of the lane polynomial at the next moment. The simulation and vehicle test results show that the prediction information can compensate for the failure of the vision sensor, and has good real-time, robustness and accuracy.

Theoretical and experimental investigation of non-asbestos friction lining material applied in automotive drum brake

2019 ◽  
Vol 234 (6) ◽  
pp. 972-985
Author(s):  
Dinesh Subhash Shinde ◽  
KN Mistry ◽  
Mukesh Bulsara
Keyword(s):  
Coefficient Of Friction ◽  
Test Procedure ◽  
Frictional Resistance ◽  
Theoretical Models ◽  
Surface Phenomenon ◽  
Vehicle Speed ◽  
Lining Material ◽  
The Coefficient Of Friction ◽  
Brake Lining ◽  
Friction Lining

Automotive brakes are the important machine element which provides an artificial frictional resistance to control the speed of an automobile. In the present work, theoretical models for the coefficient of friction between brake drum and friction liner are generated and simulated using MATLAB Simulink. A test set up designed and manufactured according to the brake lining quality test procedure (SAE J661) is used to investigate tribological properties of a non-asbestos friction lining material having 11 different constituents, which is manufactured from one of the brake liner manufacturer. An experiment is designed using response surface methodology (RSM) with vehicle speed, braking force, and sliding distance as the input parameters, whereas coefficient of friction and wear as an output. It is found that vehicle speed is the most significant parameter among the three. Fade and recovery behavior of the friction lining material is also studied and it is found that the developed friction lining material satisfies the criteria specified in SAE J661. Scanning electron microscope (SEM) and energy dispersive spectoscopy (EDS) have revealed the significant surface phenomenon.

Ti3SiC2 – A New High Temperature Solid Self-Lubricating Additive Agent

2013 ◽  
Vol 815 ◽  
pp. 626-631
Author(s):  
Li Xin Li ◽  
Xue Quan Liu ◽  
Cun Guang Ding ◽  
Yi Li ◽  
Fa Chang Li ◽  
...  
Keyword(s):  
High Temperature ◽  
Coefficient Of Friction ◽  
Dry Sliding ◽  
Dynamic Coefficient ◽  
Test Results ◽  
Tribological Test ◽  
Solid Additive ◽  
Lubricating Property ◽  
Pin On Disk ◽  
Dynamic Coefficient Of Friction

With the additive agent Ti3SiC2, the dry sliding behavior of Cr3C2-Ni and Cr3C2-Ni-Ti3SiC2 composites against GCr15 was investigated with a pin-on-disk tester at 400 °C in air under the load of 200N. Without Ti3SiC2, the dynamic coefficient of friction (COF) curves was fluctuated severely. After adding Ti3SiC2, the COF was decreased from 0.37 to 0.32, and the initial transition region of dynamic COF curve was shortened. These tribological test results showed that Ti3SiC2 was a new kind of solid additive agent with favorable high temperature self-lubricating property, and two possible mechanisms was proposed for its anti-friction ability.

Automotive Cabin Filtration In-Vehicle Test Results

1994 ◽  
Author(s):  
Robert J. Hutter ◽  
Samuel E. Lee ◽  
Kenneth L. Rubow ◽  
Benjamin Y. H. Liu
Keyword(s):  
Test Results ◽  
Vehicle Test

Utilization of ADAS for Improving Idle Stop-and-Go Control

2018 ◽  
Author(s):  
Kwangwoo Jeong ◽  
Hoon Lee ◽  
Jaihyun Lee ◽  
Sanghoon Yoo ◽  
Byungho Lee ◽  
...  
Keyword(s):  
Control Algorithm ◽  
Traffic Information ◽  
Test Results ◽  
Driver Assistance ◽  
Control Logic ◽  
Traffic Sign ◽  
Sign Recognition ◽  
Stop Sign ◽  
Stop And Go ◽  
Vehicle Test

Idle Stop and Go (ISG), also known as Automatic Engine Stop/Start, has been widely implemented in production vehicles as one of the “Eco” functions that save fuel, and the application has been promoted to meet stringent fuel economy regulations throughout the world. However, the vibration and the hesitation caused by engine stop and restart often discourage the usage. Because a conventional ISG system usually restarts the engine when it sees the brake pedal release, the driver may perceive a delay in immediate vehicle launch. Furthermore, there are some driving conditions where engine on/off is undesirable or unnecessary. A quick stop-and-go situation such as making a complete stop at a stop sign is one of the conditions where ISG would be inappropriate, and in those cases, ISG may irritate the driver or even end up increasing fuel consumption with too frequent engine stop/start. In order to mitigate aforementioned issues, a utilization of Advanced Driver Assistance System (ADAS) is proposed. With the surrounding traffic information obtained from the ADAS module, ISG control algorithm is able to determine when to turn on or off the engine prior to driver’s input. The applications demonstrated in this paper include the following usage examples: The ISG control logic monitors the movement of the vehicle in front and restarts the engine out of ISG mode before brake release, which eliminates the delay in the following vehicle launch. By employing traffic sign recognition and vehicle location info, the control logic is also able to inhibit engine off when the vehicle stops at stop signs which will avoid unwanted ISG activation. In this paper, the advanced ISG control logic is introduced, and the real-world vehicle test results are provided with the description of prototype vehicle configuration.

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