Anti-Lock Braking Performance and Hydraulic Brake Pressure Estimation

2005 ◽  
Author(s):  
Kevin O'Dea
Keyword(s):  
Braking Performance ◽  
Hydraulic Brake ◽  
Brake Pressure ◽  
Pressure Estimation

scholarly journals Pressure Estimation of the Electro-Hydraulic Brake System Based on Signal Fusion

Actuators ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 240
Author(s):  
Biaofei Shi ◽  
Lu Xiong ◽  
Zhuoping Yu
Keyword(s):  
Vehicle Dynamics ◽  
Recursive Least Squares ◽  
Hydraulic Pressure ◽  
Brake Pad ◽  
Vehicle Model ◽  
Hydraulic Brake ◽  
Signal Fusion ◽  
Brake Pressure ◽  
Pressure Estimation ◽  
Pad Wear

At present, the master cylinder pressure estimation algorithm (MCPE) of electro-hydraulic brake systems (EHB) based on vehicle dynamics has the disadvantages of poor condition adaptability, and there are delays and noise in the estimated pressure; however, the MCPE based on the characteristics of an EHB (i.e., the pressure–position relationship) is not robust enough to prevent brake pad wear. For the above reasons, neither method be applied to engineering. In this regard, this article proposes a MCPE that is based on signal fusion. First, a five-degree-of-freedom (5-DOF) vehicle model that includes longitudinal motion, lateral motion, yaw motion, and front and rear wheel rotation is established. Based on this, an algebraic expression for MCPE is derived, which extends the MCPE from a straight condition to a steering condition. Real vehicle tests show that the MCPE based on the 5-DOF vehicle model can effectively estimate the brake pressure in both straight and steering conditions. Second, the relationship between the hydraulic pressure and the rack position in the EHB is tested under different brake pad wear levels, and the results show that the pressure–position relationship will change as the brake pad is worn down, so the pressure estimated by the pressure–position model based on fixed parameters is not robust. Third, a MCPE based on the fusion the above two MCPEs through the recursive least squares algorithm (RLS) is proposed, in which the pressure-position model can be updated online by vehicle dynamics and the final estimated pressure is calculated based on the updated pressure–position model. Finally, several simulations based on vehicle test data demonstrate that the fusion-based MCPE can estimate the brake pressure accurately and smoothly with little delay and is robust enough to prevent brake pad wear. In addition, by setting the enabling conditions of RLS, the fusion-based MCPE can switch between driving and parking smoothly; thus, the fusion-based MCPE can be applied to all working conditions.

Collaborative control of a dual electro-hydraulic regenerative brake system for a rear-wheel-drive electric vehicle

2018 ◽  
Vol 233 (4) ◽  
pp. 1035-1046 ◽  
Author(s):  
Jonathan Nadeau ◽  
Philippe Micheau ◽  
Maxime Boisvert
Keyword(s):  
Electric Vehicle ◽  
Energy Recovery ◽  
Rear Wheel ◽  
Brake System ◽  
Force Distribution ◽  
Hydraulic Brake ◽  
Brake Pressure ◽  
Wheel Drive ◽  
Brake Force ◽  
Brake Force Distribution

Within the field of electric vehicles, the cooperative control of a dual electro-hydraulic regenerative brake system using the foot brake pedal as the sole input of driver brake requests is a challenging control problem, especially when the electro-hydraulic brake system features on/off solenoid valves which are widely used in the automotive industry. This type of hydraulic actuator is hard to use to perform a fine brake pressure regulation. Thus, this paper focuses on the implementation of a novel controller design for a dual electro-hydraulic regenerative brake system featuring on/off solenoid valves which track an “ideal” brake force distribution. As an improvement to a standard brake force distribution, it can provide the reach of the maximum braking adherence and can improve the energy recovery of a rear-wheel-drive electric vehicle. This improvement in energy recovery is possible with the complete substitution of the rear hydraulic brake force with a regenerative brake force until the reach of the electric powertrain constraints. It is done by performing a proper brake pressure fine regulation through the proposed variable structure control of the on/off solenoid valves provided by the hydraulic platform of the vehicle stability system. Through road tests, the tracking feasibility of the proposed brake force distribution with the mechatronic system developed is validated.

Analysis of Effect on Change Rate of Wheel Cylinder Pressure for Electro-Hydraulic Brake System of Electric Vehicle

2012 ◽  
Vol 209-211 ◽  
pp. 2094-2099
Author(s):  
Xiu Yuan Xing ◽  
Ze Chang Sun ◽  
Meng Wang
Keyword(s):  
Electric Vehicle ◽  
Pressure Change ◽  
Brake System ◽  
Impact Factors ◽  
Cylinder Pressure ◽  
Change Rate ◽  
Hydraulic Brake ◽  
Brake Pressure ◽  
New Type ◽  
The Impact

Based on a new type of electro-hydraulic brake system of electric vehicle, the operating principle was studied. A model of hydraulic brake system and corresponding control strategy were built with the co-simulation platform of AMESim and MATLAB. The impact factors of brake pressure change rate were analyzed theoretically. The influences of the main hydraulic parameters were analyzed through simulation, such as volume of brake fluid, type of pipe, ABS valve and brake clearance. The results provide a theoretical basis for the accurate control of wheel cylinder pressure.

Analysis of Braking Energy Recovery in EV with EHB

2014 ◽  
Vol 986-987 ◽  
pp. 1183-1186
Author(s):  
Liang Zhou ◽  
Meng Yang Zhao ◽  
Xin Yu Wang ◽  
Xi Chao Li
Keyword(s):  
Electric Vehicles ◽  
Recovery Rate ◽  
Energy Flow ◽  
Energy Recovery ◽  
Regenerative Braking ◽  
Hydraulic Pump ◽  
Braking Performance ◽  
Hydraulic Brake ◽  
Simulation Results ◽  
Braking Energy Recovery

The battery ability of recovering electricity plays a significant role in improving the regenerative braking performance. In this paper, a control for recovery of braking energy in Electric Vehicles (EVs) with electro hydraulic brake (EHB) is proposed, which makes the recovery transfer to the electric hydraulic pump of EHB directly, rather than being stored statically in the battery. An energy flow strategy was designed for the maximum braking energy recovery based on this control. The simulation results show higher energy recovery rate in comparison to the general recycling control.

Friction and Wear Properties of Aluminum Matrix Composites and its Application

2007 ◽  
Vol 351 ◽  
pp. 147-150
Author(s):  
Qiu Bao Ouyang ◽  
H.L. Gu ◽  
W.L. Wang ◽  
Di Zhang ◽  
Guo Ding Zhang
Keyword(s):  
Friction And Wear ◽  
Aluminum Matrix ◽  
Aluminum Matrix Composites ◽  
Matrix Composites ◽  
Wear Properties ◽  
Braking Performance ◽  
Brake Pressure ◽  
Friction And Wear Properties ◽  
Sic Composites ◽  
Sic Particle

Friction and wear properties of aluminum matrix composites are studied, including brake speed, brake pressure, and surface temperature etc. A conclusion can be drawn that SiC particle reinforced aluminum matrix composites are of stable friction coefficient, high thermal conductivity, and excellent wear-resistance. Hubs of motorcycle with brake rings of Al/SiC composites were manufactured and exhibited an excellent braking performance.

scholarly journals Research on Optimal Control of Excavator Negative Control Swing System

Processes ◽  
2020 ◽  
Vol 8 (9) ◽  
pp. 1096
Author(s):  
Lijie Zhang ◽  
Wenbo Fu ◽  
Xiaoming Yuan ◽  
Zhaoliang Meng
Keyword(s):  
Control Strategy ◽  
Power Flow ◽  
Negative Control ◽  
System Response ◽  
Hydraulic Brake ◽  
Compound Control ◽  
Brake Pressure ◽  
System Response Time ◽  
Swing Speed ◽  
System Power

In order to improve the energy efficiency and dynamic of negative control swing systems of excavators, this paper proposes a technical scheme of adding two PRVs (pressure reducing valves) to main valve pilot control circuit, which can adjust main value opening arbitrarily according to the working condition. A pump-value compound control strategy was formulated to regulate the system power flow. During swing motor acceleration, main pump and the two PRVs are controlled to match system supply flow with motor demand flow, thereby reducing motor overflow and shortening system response time. During swing motor braking, the channel from motor to tank is opened to release hydraulic brake pressure by controlling PRVs before swing speed reduces to zero, which prevents the motor from reversing and oscillating. A simulation model of 37-ton excavator was established, and the control strategy was simulated. The original and optimized performance of the swing system were compared and analyzed, and results show that the application of new scheme with the compound control strategy can reduce overflow and increase braking stability of the swing system. In addition, system response and speed control performance are also improved when excavator performs a single-swing action.

Discontinuously Reinforced Aluminum Composite and Its Application in Brake Discs

2006 ◽  
Vol 313 ◽  
pp. 31-36 ◽  
Author(s):  
Qiu Bao Ouyang ◽  
Wen Long Wang ◽  
Di Zhang ◽  
Guo Ding Zhang
Keyword(s):  
Thermal Conductivity ◽  
Wear Resistance ◽  
Large Range ◽  
Automotive Application ◽  
Light Weight ◽  
Test Results ◽  
Aluminum Composite ◽  
Braking Performance ◽  
Brake Pressure ◽  
Brake Discs

Discontinuously reinforced aluminum (DRA) composites are attractive for a large range of engineering applications because of its excellent wear-resistance, high thermal conductivity and light weight etc. In this paper, DRA composites were designed and fabricated especially for automotive application, and their properties were measured. Brake discs of DRA composites were manufactured and their braking performances were investigated, including brake velocity, brake pressure, brake torque, brake deceleration, brake time and surface temperature etc. The test results show DRA composites exhibit an excellent braking performance.

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.

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