20-09-2017, 11:26 AM
Electrohydraulic brake system (EHB) is a system that detects the will of the driver to brake through the pedal simulator and controls the braking pressures of each wheel. The system is also a hydraulic brake system by wire. Many of the vehicle sub-systems in today's modern vehicles are being converted into "by-wire" type systems.
This normally implies a function, which in the past was activated directly through a purely mechanical device, is now implemented by electromechanical means by signal transfer to and from an electronic control unit.
Optionally, the ECU can apply additional "intelligence" based on the input of other sensors outside the influence of the driver. The Electrohydraulic Brake is not a true by-wire system with the thought process that physical wires do not extend to the wheel brakes. However, in the true sense of the definition, any EHB vehicle can be braked with an electric joystick completely independent of the traditional brake pedal. It simply happens that the hydraulic fluid is used to transmit power from the actuator to the wheel brakes.
This configuration offers the distinct advantage that today's production wheel brakes can be maintained while a manually applied integrated hydraulic safety backup system can be incorporated directly into the EHB system. The cost and complexity of this approach typically compare favorably with an electromechanical brake (EMB) system, which requires a significant reversal in the vehicle's fail-safe electrical architecture, and some require a 42-volt power source. Therefore, the EHB can be classified as a "stone of progress" technology to complete electromechanical brakes
A base braking event may be described as a normal or typical stop where the driver holds the vehicle in its intended direction at a controlled deceleration level that does not approach close to the wheel lock. All other braking events where additional intervention may be required, such as wheel brake pressure control to prevent locking, application of a wheel brake to transfer the torque through an open differential or application of a torque induced to one or two wheels selected to correct a lower or higher steering condition can be classified as controlled brake performance.
Field statistics indicate that most of the braking events come from base brake applications and, as such, can be classified as the most important function. From this perspective, it may be of interest to compare modern electrohydraulic brake (EHB) systems with a conventional vacuum brake application system and observe the various design options used to achieve performance and reliability targets.
It can be understood in the following video:
This normally implies a function, which in the past was activated directly through a purely mechanical device, is now implemented by electromechanical means by signal transfer to and from an electronic control unit.
Optionally, the ECU can apply additional "intelligence" based on the input of other sensors outside the influence of the driver. The Electrohydraulic Brake is not a true by-wire system with the thought process that physical wires do not extend to the wheel brakes. However, in the true sense of the definition, any EHB vehicle can be braked with an electric joystick completely independent of the traditional brake pedal. It simply happens that the hydraulic fluid is used to transmit power from the actuator to the wheel brakes.
This configuration offers the distinct advantage that today's production wheel brakes can be maintained while a manually applied integrated hydraulic safety backup system can be incorporated directly into the EHB system. The cost and complexity of this approach typically compare favorably with an electromechanical brake (EMB) system, which requires a significant reversal in the vehicle's fail-safe electrical architecture, and some require a 42-volt power source. Therefore, the EHB can be classified as a "stone of progress" technology to complete electromechanical brakes
A base braking event may be described as a normal or typical stop where the driver holds the vehicle in its intended direction at a controlled deceleration level that does not approach close to the wheel lock. All other braking events where additional intervention may be required, such as wheel brake pressure control to prevent locking, application of a wheel brake to transfer the torque through an open differential or application of a torque induced to one or two wheels selected to correct a lower or higher steering condition can be classified as controlled brake performance.
Field statistics indicate that most of the braking events come from base brake applications and, as such, can be classified as the most important function. From this perspective, it may be of interest to compare modern electrohydraulic brake (EHB) systems with a conventional vacuum brake application system and observe the various design options used to achieve performance and reliability targets.
It can be understood in the following video: