Sensotronic Brake Control

Last updated

Sensotronic Brake Control (SBC) is an electro-hydraulic brake system, where the wheel brake cylinders on a vehicle are operated through a servomechanism.

Contents

The SBC system developed by Daimler and Bosch was introduced on the R230 SL-class, which went on sale in Europe in October 2001. [1]

Mechanics

The SBC operates the brakes using a brake fluid supply from a hydraulic high-pressure reservoir. A piston pump driven by an electric motor supplies a controlled brake fluid pressure at range between 140 bars (2,000 psi) and 160 bars (2,300 psi) in the gas diaphragm reservoir. [2]

When the brakes are applied, the SBC control unit will calculate the desired target brake pressures on each individual wheel. The system uses four independent pressure modulators to regulate a hydraulic pressure at each wheel. The pressure modulators consist of one inlet and one outlet valve, controlled by electronic output stages.

The system employs a travel sensor and a pressure sensor at the pedal to measure the speed and force. The control unit processes this information and generates the control signals for the wheel pressure modulators. Normally, the master brake cylinder is detached from the brake circuit. A pedal travel simulator creates normal pedal feedback. If ESP intervenes, the high-pressure reservoir supplies the required brake pressure quickly and precisely to selected wheels.

Advantages and disadvantages

With fine-grained control of pressure at each wheel, SBC allows for the implementation of traditional stability control methods, such as Anti-lock braking system (ABS) and Electronic Stability Program (ESP). The system offers electronically controlled functions intended to reduce the driver's workload. Traffic Jam Assist brakes the vehicle automatically in stop-and-go traffic once the driver takes his or her foot off the accelerator. The Soft-Stop function assists with smooth stopping in town traffic by reducing braking pressure.

In case of computer failure, SBC reverts to a hydraulic master cylinder, but driver effort and stopping distance is reported to increase. [3] In case of pump failure the high-pressure reservoir is capable of retaining enough pressure to stop the vehicle electronically.

Industry recognition

In 2001 the μ-Club, an association of international experts in the field of brake technology, honored Robert Bosch and Daimler Chrysler for the development of the electrohydraulic brake SBC.

Problems

In May 2004, Mercedes recalled 680,000 vehicles equipped with the system; in March 2005 a total of 1.3 million vehicles were recalled. In 2006 high-volume models such as the E-class returned to conventional hydraulic brake systems. Low-volume luxury models such as the SL, the Maybach and the SLR continued to use SBC due to the prohibitive cost of redesign. [3]

In a letter to US customers dated August 2018, a warranty addendum was sent extending coverage for 25 years and unlimited miles on the following SBC components:

Sensotronic Brake Control applications

Other production electro-hydraulic brake systems

Related Research Articles

<span class="mw-page-title-main">Anti-lock braking system</span> Safety anti-skid braking system used on aerospace and land vehicles

An anti-lock braking system (ABS) is a safety anti-skid braking system used on aircraft and on land vehicles, such as cars, motorcycles, trucks, and buses. ABS operates by preventing the wheels from locking up during braking, thereby maintaining tractive contact with the road surface and allowing the driver to maintain more control over the vehicle.

<span class="mw-page-title-main">Brake</span> Mechanical device that inhibits motion

A brake is a mechanical device that inhibits motion by absorbing energy from a moving system. It is used for slowing or stopping a moving vehicle, wheel, axle, or to prevent its motion, most often accomplished by means of friction.

<span class="mw-page-title-main">Electronic stability control</span> Computerized safety automotive technology

Electronic stability control (ESC), also referred to as electronic stability program (ESP) or dynamic stability control (DSC), is a computerized technology that improves a vehicle's stability by detecting and reducing loss of traction (skidding). When ESC detects loss of steering control, it automatically applies the brakes to help steer the vehicle where the driver intends to go. Braking is automatically applied to wheels individually, such as the outer front wheel to counter oversteer, or the inner rear wheel to counter understeer. Some ESC systems also reduce engine power until control is regained. ESC does not improve a vehicle's cornering performance; instead, it helps reduce the chance of the driver losing control of the vehicle.

<span class="mw-page-title-main">Hydropneumatic suspension</span> Pneumatics

Hydropneumatic suspension is a type of motor vehicle suspension system, designed by Paul Magès, invented by Citroën, and fitted to Citroën cars, as well as being used under licence by other car manufacturers. Similar systems are also widely used on modern tanks and other large military vehicles. The suspension was referred to as suspension oléopneumatique in early literature, pointing to oil and air as its main components.

<span class="mw-page-title-main">Mercedes-Benz 300 SL</span> Mercedes coupe/convertible (1954–1963)

The Mercedes-Benz 300 SL is a two-seat sports car that was produced by Mercedes-Benz from 1954 to 1957 as a gullwinged coupé and from 1957 to 1963 as a roadster. The 300 SL traces its origins to the company's 1952 racing car, the W194, and was equipped with a mechanical direct fuel injection system that significantly increased the power output of its three-liter overhead camshaft straight-six engine.

<span class="mw-page-title-main">Electronic brakeforce distribution</span>

Electronic brakeforce distribution or electronic brakeforce limitation (EBL) is an automobile brake technology that automatically varies the amount of force applied to each of a vehicle's wheels, based on road conditions, speed, loading, etc, thus providing intelligent control of both brake balance and overall brake force. Always coupled with anti-lock braking systems (ABS), EBD can apply more or less braking pressure to each wheel in order to maximize stopping power whilst maintaining vehicular control. Typically, the front end carries more weight and EBD distributes less braking pressure to the rear brakes so the rear brakes do not lock up and cause a skid. In some systems, EBD distributes more braking pressure at the rear brakes during initial brake application before the effects of weight transfer become apparent.

<span class="mw-page-title-main">Drive by wire</span> Automotive technology

Drive by wire or DbW technology in the automotive industry is the use of electronic or electro-mechanical systems in place of mechanical linkages that control driving functions. The concept is similar to fly-by-wire in the aviation industry. Drive-by-wire may refer to just the propulsion of the vehicle through electronic throttle control, or it may refer to electronic control over propulsion as well as steering and braking, which separately are known as steer by wire and brake by wire, along with electronic control over other vehicle driving functions.

<span class="mw-page-title-main">Mercedes-Benz E-Class (W210)</span> Motor vehicle

The Mercedes-Benz W210 is the internal designation for a range of executive cars manufactured by Mercedes-Benz and marketed under the E-Class model name in both sedan/saloon (1995–2002) and station wagon/estate (1996–2003) configurations. W210 development started in 1988, three years after the W124's introduction.

<span class="mw-page-title-main">Mercedes-Benz E-Class (W211)</span> Motor vehicle

The Mercedes-Benz W211 is the third generation Mercedes-Benz E-Class made from 2001 to 2009 in sedan/saloon and station wagon/estate configurations – replacing the W210 E-Class models and superseded by the Mercedes-Benz W212 in 2009.

<span class="mw-page-title-main">Mercedes-Benz SL-Class (R129)</span> Roadster which was produced by Mercedes-Benz from 1989 until 2001.

The Mercedes-Benz R129 SL is a roadster which was produced by Mercedes-Benz from 1988 until 2001. The R129 replaced the R107 in 1989 and was in its turn replaced by the R230 SL-Class in 2002 for the 2003 model year.

<span class="mw-page-title-main">Active Body Control</span> Type of automobile suspension technology

Active Body Control, or ABC, is the Mercedes-Benz brand name used to describe electronically controlled hydropneumatic suspension.

<span class="mw-page-title-main">4Matic</span> All-wheel-drivetrain developed by Mercedes-Benz

4Matic is the marketing name of an all-wheel drive system developed by Mercedes-Benz. It is designed to increase traction in slippery conditions. With the introduction of the 2017 E 63 S sedan, Mercedes-AMG announced a performance-oriented variant of the system called AMG Performance 4MATIC+.

<span class="mw-page-title-main">Mercedes-Benz S-Class (W221)</span> German luxury sedan

The Mercedes-Benz W221 is a chassis code of the fifth generation S-Class produced from August 2005 until June 2013.

<span class="mw-page-title-main">Hydraulic brake</span> Arrangement of braking mechanism

A hydraulic brake is an arrangement of braking mechanism which uses brake fluid, typically containing glycol ethers or diethylene glycol, to transfer pressure from the controlling mechanism to the braking mechanism.

<span class="mw-page-title-main">Mercedes-Benz Actros</span> German heavy-duty truck

The Mercedes-Benz Actros is a heavy-duty truck introduced by Mercedes-Benz at the 1996 Commercial Vehicle IAA in Hanover, Germany, as the replacement for the SK. It is normally used for long-distance haulage, heavy-duty distribution haulage, and construction haulage. It is powered by an inline-6 diesel engine with a turbocharger and intercooler. Daimler Trucks/Lorries launched version II of the Actros in 2002 and version III in 2007. The fourth generation of the Actros, officially named "the New Actros," launched in July 2011.

<span class="mw-page-title-main">Brake-by-wire</span> Automotive technology

Brake-by-wire technology in the automotive industry is the ability to control brakes through electronic means, without a mechanical connection that transfers force to the physical braking system from a driver input apparatus such as a pedal or lever.

<span class="mw-page-title-main">Mercedes-Benz C112</span> Mid-engine concept car developed by German automobile manufacturer Mercedes Benz in 1991

The Mercedes-Benz C112 was an experimental mid-engine concept car built in 1991 by German automobile manufacturer Mercedes-Benz as a test bed, similar to the later versions of the C111. Despite using the same chassis code, it was not related to the W112 series of limousines and coupes of the 1960s. The C112 was intended to be the road-legal counterpart of the Sauber-built C11 Group C prototype race car developed for the 1990 World Sports-Prototype Championship.

<span class="mw-page-title-main">Mercedes-Benz S-Class (W222)</span> Motor vehicle

The Mercedes-Benz W222 is the sixth generation of S-Class produced from 2013 to 2020, successor of the W221 S-Class and predecessor to the W223 S-Class. The W222 was designed in 2009 by Korean designer Il-hun Yoon, who was inspired by the Mercedes-Benz F700 concept car. The exterior design was developed by a team of designers under the direction of Robert Lešnik. The W222 has a similar design theme to the C-Class (W205) and E-Class (W213).

<span class="mw-page-title-main">Unimog 405</span> Motor vehicle

The Unimog 405 is a vehicle of the Unimog-series by Mercedes-Benz, made by Daimler Truck Holding AG. Developed in the 1990s, the Unimog 405 has been in production since 2000. Originally, DaimlerChrysler produced the Unimog at Gaggenau; in 2002, production was moved to Wörth am Rhein. The Unimog 405 is the implement carrier version of the Unimog and the successor to most previous Unimogs. Although retaining many characteristics typical of the Unimog, the 405's axle and chassis design concept with control arms instead of torque tubes marks a "paradigmatic change" in Unimog design.

References

  1. "Mercedes' luxury transformer". NZ Herald. 2001-08-11. Retrieved 2009-07-31.
  2. "Sensotronic Brake Control: System Information". Bayhas.com. Retrieved 2017-03-25.
  3. 1 2 "Mercedes cancels by-wire brake system; decision a blow to technology's future: AutoWeek Magazine". Autoweek.com. 2005-12-15. Retrieved 2018-07-01.