Category:Car Safety

From Eurêka

Contents 1 Car Safety 2 Road Worthiness 3 Active Safety 4 Steering 5 Braking 6 Passenger Safety 7 Air Bags 8 Rollover 9 Fuel Tank Integrity 10 Ford Lawsuits 11 Seat Belts 12 Car Safety Standards

Car Safety

Car safety Creating a car with safety features built in.

Passive safety Safety features built into a car which only operate during a crash.

Care safety package Comprehensive package of safety equipment including collapsible steering wheels, safety locks to keep doors flying open on impact, shatter-resistance rear-view mirrors, and, as options, seat belts, padded sun visors and padded dashboards, introduced by Ford in its 1956 models.

Note In 1956, Ford promoted safety features, Chevrolet speed: the public chose speed.

Bumper (Fender) Protective bar across front and back of the car, pneumatic design manufactured by the Simms Manufacturing Co., Kilburn, London, 1905.

Bull bars Steel grating used by four-wheeled drive, jeep-type vehicles, developed for use in Australian outback for protection against kangaroos. In urban conditions they represent a danger to pedestrians.

Mud flap (Mud guard) Flap to prevent tire splash on a car.

Splash guard Flap suspended behind a rear wheel to prevent tire splash from muddying windshields of following vehicles.

Roll bar Overhead metal bar on an automobile that is designed to protect the occupant in case of a rollover

Death seat (AuE) Seat opposite the driver of a car because it is the most dangerous.

1. Shotgun Death seat in US, reference to stagecoach days.

Road Worthiness

Road worthiness Condition of a vehicle to be fit to go on the road.

1. MOT test (BrE) Compulsory annual road worthiness test that has to be taken after a car is three years old.

Driveability (Driver friendliness) Degree of ease/difficulty in operating and controlling a vehicle, a general qualitative evaluation of a powertrain's operating qualities, including idle smoothness, cold and hot starting, throttle response, power delivery, and tolerance for altitude changes.

Field of view Driver’s horizontal range of visibility through the windshield, side and rear windows, and inside/outside mirrors.

1. Blind Spot Areas around a vehicle that are not visible to the driver either through the windshield, side windows or mirrors.

Driver preferences Seat position, mirror angles, radio stations and other adjustments favored by driver.

NVH index (engineers’ term) Noise, vibration and harshness index.

Federalized (AmE) Said of any car that has passed the Federally regulated tests that permit a vehicle to be sold in the US. Tests relate to safety features and emission standards.

1. Crashworthiness regulations (AmE) Federal regulations requiring a high level of protection from crashes.

Bac-A-Larm System that beeps a warning when trucks and other heavy machinery are backing up, invented by Ed Peterson (1921-1999), first sold 1967.

E-mark Plate on new cars showing which European safety, emissions and other standards with which they comply.

Active Safety

Active safety All those characteristics in a car’s design which may help a driver avoid accidents.

Roadholding Ability of a car to grip the pavement.

1. Lateral acceleration Technical term for roadholding because cornering is actually a continuous deviation from a straight path. Measured in gs.
2. Wet roadholding Degree of stability of a car on wet roads.
3. Dry roadholding Degree of stability of a car on dry roads.

Handling Feel of driving car.

1. Stability Handling over bumps, at speed, and in cross-winds.
2. Predictability Overall predictability of behavior.

Suspension roll Side-to-side or roll or the sprung mass of a vehicle with respect to its undercarriage.

1. Antidive Suspension characteristic in which the downward force on the front of a vehicle, caused by the transfer of a vehicle's weight when braking, is resisted.
   1. Antidive geometry Arrangement of the front suspension to minimize or eliminate nose dipping while braking, partly for comfort and partly to maintain adhesion and stability.
2. Antisquat Suspension characteristic in which the downward force on the rear of a vehicle, caused by the transfer of a vehicle's weight when accelerating, is resisted.
3. Compliance Slight resiliency, or “give,” designed into suspension bushings to help absorb bumps. Good compliance allows the wheels to move rearward a bit as they hit bumps but doesn't allow them to move laterally during cornering.

Axle tramp Violent movement of the driven wheels like somebody stamping their feet rapidly on the floor, caused by the sudden oscillation of a poorly located axle.

Steering

Steering feel Driver’s subjective feelings about the way a car steers, a general relationship between forces at the steering wheel and handling. Ideally, the steering effort should increase smoothly as the wheel is rotated away from center. In addition, the steering effort should build as the cornering forces at the steered wheels increase. Finally, the friction built into the steering mechanism should be small in comparison with the handling-related steering forces.

Steering gain Relationship between yaw and the steering wheel's position and effort. All three should be proportional and should build up smoothly.

Steering response Subjective term that combines steering feel and steering gain.

1. Steering stability Degree to which a vehicle maintains a direction of travel without driver corrections and returns to the desired direction after being misdirected.
   1. Steering angle Angle between the longitudinal axis of a vehicle and the plane of the steered wheel.
   2. Steering ratio Ratio of angular turning of the steering wheel to the corresponding angular turning of the steered wheels.
2. On-center feel Responsiveness and feel of the steering when the wheel is approximately centered. In a car with good on-center feel, the steering wheel tends to return to center when slightly deflected, assisting straight-line stability.

Straight-line tracking Ability of a car to resist road irregularities and run in a straight line without steering corrections.

Opposite lock Technique in which the steering wheel is turned in the direction away from where the car is turning, used to control a car when it is oversteering and its tail is swinging wide.

Steering axis Line that intersects the upper and lower steering pivots on a steered wheel. On a car with a strut suspension, the steering axis is defined by the line through the strut mount on top and the ball joint on the bottom.

Steering geometry Group of design variables outside the steering mechanism that affect steering behavior, including camber, caster, linkage arrangement, ride steer, scrub radius, toe-in, and trail.

Power steering Assist provided by the engine to reduce steering effort. Essential to make large, heavy vehicles manageable. Small vehicles often do not require power steering.

Directional stability Tendency for a tire to roll in it’s steered direction rather than follow road contours.

1. Oversteer Situation that occurs in cornering when the rear of a vehicle tends to go into a rear-wheel skid.
   1. Loose (slang) Oversteer, so named because its tail tends to swing wide.
2. Understeer Condition that exists during cornering when the front of a vehicle tends to resist turning and continues straight ahead in a front-wheel skid.
   1. Push (slang) Understeer.
3. Neutral steer Cornering condition in which the front and rear slip angles are roughly the same. Although seemingly an ideal state of balance, perfect neutral steer is not as stable as slight understeer.
4. Ride steer (Bump steer) Undesirable condition in which a wheel steers slightly as its suspension compresses or extends.
5. Toe steer Changes in the direction of a wheel that occur without driver steering input that can be caused by ride steer or by deflections in suspension components caused by the stresses of cornering, accelerating, and/or braking on smooth and bumpy roads.
6. Torque steer Tendency for a car to turn in a particular direction when power is applied, common in front-drive cars because reaction forces created in the half-shafts can generate uneven steering forces in the front tires.

Braking

Braking Process of slowing and/or halting the car.

1. Brake fade Declining effectiveness of car brakes when applied for a long period due to overheating. Braking surfaces become very hot and the frictional properties of the break linings deteriorate.
2. Braking distance Distance it takes a vehicle to stop after the brakes have been applied.
3. Cadence braking Delicately controlled on/off application of the brakes in rhythm with the natural bounce frequency of the front suspension to help stop a car quickly on a slippery surface without locking the wheels and losing control.
4. Judder Vibration felt during braking, usually when braking hard from high speed.
5. Dive Dipping of a car’s nose that occurs when the brakes are applied, caused by a load transfer from the rear to the front suspension.
6. Squat Opposite of dive, squat is the dipping of a car’s rear end that occurs during hard acceleration. Squat is caused by a load transfer from the front to the rear suspension.

Trail-braking Driving technique in which the driver begins to brake before entering a turn and then continues to brake as he eases into the corner. As cornering forces build, the driver gradually feathers off the brakes: trading braking power for cornering grip. By increasing the vertical loading: and thus the traction, at the front tires, trail-braking can improve a car's turn-in.

Passenger Safety

Car seat laws Child must use a car seat until a specified weight and height and age. Laws vary depending on country.

Passenger seat laws Legislation that mandates the use of some form of restraint on passengers to protect them from injury in vehicular accidents.

Air Bags

Air bag Bag that inflates at the moment of impact in an accident, and protects the driver and passenger from impacting on dashboard and windscreen.

1. Depowered air bag (Less-force air bag; Next-generation air bag; Reduced-force air bag; Second-generation air bag) Air bag that inflates with about 25-30% less force, introduced in US 1998.
2. Dual air bags Air bags for both driver and passenger in the front seat.
   1. Driver-side air bag Air bag fitted in the steering wheel.
   2. Passenger-side air bag Air bag is located in various places on the instrument panel.
   3. Side-impact rail Cylindrical air bag that inflates to protect front seat people from a side impact.
3. Forward-deploying bag Deploys forward, creating less distance between the passenger’s body and the point where the bag begins to inflate.
4. Smart bags Air bags that inflate only if the nature of the crash and the size of the passenger indicates this is the better course.
5. Unfurling power Amount of power that is triggered by an accident. Generally an air bag deploys between 150 to 200 mph, and is designed to be fully inflated by the time it makes contact.
   1. Collision sensor Device that measures the severity of a car’s change in velocity that triggers the air bag.
   2. Crash pulse Change in velocity from which to calculate whether and when to deploy the air bag.
6. Upward-deploying bag Deploys upward and inflates against the windshield, allowing more space between the passenger and the air bag.
7. Rollover bag Curtain that inflates over front and rear side windows and stays inflated up to 6 seconds to cushion drivers’ and passengers’ heads long enough to outlast a multiple-rollover wreck, designed by Ford for its SUVs, first installed on 2001 model.
8. Great rollover scare Consumer Report of the Consumer Union found the Suzuki Samurai “not acceptable” because of a test that showed it liable to rollover, 1988. That put the Samurai out of business in the US and began a long process of litigation. In 1989, Ford Bronco II was found to have poor emergency handling. In 1996, the Trooper and its twin Acura SLX showed that it could rollover and was “unacceptable.” Isuzu brought a case against the Consumer Union, but a Los Angeles jury found the Consumer Union had made several false statements in an article and at a news conference but these were not malicious or damaged Isuzu, 7 April 2000.

Rollover

Rollover ratings Measure based on static stability ratio.

1. Static stability ratio Vehicle’s width to twice the height of its center of gravity.
2. Safety rating frequency of rolling over in a single vehicle crash.
   1. ***** = less than 10% (ratio range 1.45 or more)
   2. **** = 10 to 20% (1.25-1.44)
   3. *** = 20 to 30% (1.13-1.24)
   4. ** = 30 to 40% (1.05-1.12)
   5. * = 40% or more (1.04 or less)

Frontal crash ratings Star rating system developed by traffic safety agency, 1979.

Windscreen glass controversy Debate in Britain over the merits of laminated or toughened glass.

Cushioned fascias Protection for driver/passenger in front seat on impact.

1. Padded dashboard US Congress passed legislation for mandatory padded dashboards, 1966.
2. Padded sun visors Additional protection during an accident.

Curb feeler (Curb marker; Curb warning) Wire spring attached to the lower right side of a vehicle that emits a sound audible to the driver when it hits the curb.

Fuel Tank Integrity

Fuel tank integrity Attempts in the US to improve fuel-tank integrity, reducing the risk of fires.

Fuel tank fire Problem of cars whose fuel tanks are located too close to the rear so that they are unduly liable to fire in rear end collisions.

1. Ford Pinto lawsuit (Pinto lawsuit) Personal injury case against Ford Motor Co. with a fuel-tank fire problem, in which $128 million was awarded in punitive and compensatory damages, later reduced to $7 million, late 1970s.
2. Oldsmobile Cutlass lawsuit Personal injury case against General Motors brought by family of a boy killed in a fuel-tank fire in 1983 who were awarded $60 million damages, later reduced to $33 million.
3. Chevrolet Malibu lawsuit Personal injury case against General Motors brought by victims who were badly burned because the gas tank of the car was installed just behind the back bumper. The plaintiffs were awarded $4.9 billion damages, the highest in US history, 9 July 1999.
   1. Ivey memo Document one and a half pages long written by GM engineer, Edward C. Ivey that calculated the cost to the company of deaths because of the location of the fuel tank, 1973.
   2. Value analysis Ivey memo showed that fuel tank fires were costing the company $2.40 per vehicle.
   3. General Motors cover-up General Motors kept the Ivey memo secret from 1981 until a judge threatened very severe sanctions if GM did not produce the memo, 1998.
   4. Fire babies Nickname given to 6 law firms hired by General Motors to scour its records for documents relating to damaging fire injuries in its vehicles.

Note The fuel tank of the Chevrolet Malibu was moved forward in 1984.

Ford Lawsuits

Ford lawsuits Series of legal actions related to Ford cars, early 2000s.

1. Defective ignition systems Class-action suit raised in California against Ford on behalf of car owners who claimed the company knowingly installed defective ignition systems. Ford was found liable by judge, Michael E. Ballachey of concealing from regulators and customers a design flaw affecting 22 million cars produced 1983-1995.
2. Bronco rollover dispute Ford faced claims of at least $2.4 billion for using a faulty design that increased the chances of a rollover, 2001.
3. Asbestos-related ailment dispute Legal dispute for at least $1.7 billion for asbestos-related ailments, 2001.
4. Defective restraint system dispute Legal dispute for at least $600 million over a defective restraint system, 2001.

Seat Belts

Seat belts (Safety belts) Belts anchored in the car to hold the person on their seat in an accident.

1. Lap belt Seat belt that straps directly over the lap with the buckle in the abdomen that often caused internal injuries.
2. Front seat belts Belts on driver and front passenger seats, prodded by laws in 23 US states, car makers installed front seat belts as standard 1964.
3. Shoulder belt Seat belt that crosses the shoulder to the lap diagonally. US Congress passed legislation for mandatory shoulder belts, along with padded dashboards and emergency flashers, 1966.
4. Three-point belt Introduced in Sweden, invented by Nils Bohlin of Volvo, 1958.

Note Volvo estimates that the three-point belt saved more than one million lives in its first 40 years.

“Don’t forget to buckle up” Slogan used to encourage use of seat belts.

Child restraints (Child safety seats) Safety seats that can be mounted on a car seat for an infant or child. Single-largest cause of death among children 15 or younger is a car accident.

1. Infant seat (Baby seat; Rear-facing baby seat) Seat is mounted with the child facing the rear, especially designed for infants up to age 1 and 20 pounds.
2. Child seat Forward-facing seat designed for a child who weighs at least 20 lbs and is at least one year old.
3. Convertible seat Seat that can face either front or back of a car, depending on a child’s age and weight, used from birth until a child weighs 40 lbs.
4. Booster seat Seat for a child who has outgrown a convertible or child’s seat, but is still too small for a regular seat belt.
5. Integrated child safety seat Restraint built into the rear seatback to secure and protect small children.

Locking clip Special device used when the vehicle's lap/shoulder belts do not lock and will help secure a child safety seat tightly into a vehicle.

Tether anchors Standardized child safety seat system that uses special anchors in the vehicles' seats, combined with tethers on the child safety seat, to secure a child safety seat tightly.

Seat belt issue Debate over the loss of civil liberties by forcing people to use seat belts.

Submarining Sliding under a car seat belt during a crash because it has been worn too high.

Air bag hazards Air bags are dangerous if the driver and passenger are less than 12 inches away from the source of the bag for the impact will be too strong. Rear-facing infant seats protrude too far forward. Children who are not belted, or who are so small they slip through are also in danger.

Air bag death Person, especially a baby in a rear-facing child safety seat, a child, elderly person or an adult woman of small stature, being killed by the unfurling force of the air bag.

Car Safety Standards

National Highway Safety Administration Federal organization responsible for car and highway safety.

1. National Advanced Driving Simulator (NADS) World’s first 360-degree, high-fidelity sound and motion system with 24-foot high projection dome perched on 6 hydraulic legs above a track system, is designed to surround experimental subjects with realistic road images, located at Iowa City, began operation June 2000.
   1. Actuators Supports in NADS that replace wheels in test vehicles, connecting to the axles to provide bumps, shakes and a realistic driving feel when turning.
   2. Belt/rail system Dome is propelled by a moving belt and rides on two rails, allowing it to travel back and forth along one axis, used to simulate spin.
   3. Turntable Device that allows the whole dome to spin, increasing realism during spins.
   4. Hydraulic legs Legs contain pistons that move rapidly up and down, simulating uphill or downhill travel, rough terrain or accidents.

Note Data collected by the Safety Administration show that 90% of the highway deaths each year are caused by human errors not mechanical malfunctions.

Motor Vehicle Safety Act (MVSA) Legislation which regulates the manufacture and importation of motor vehicles and motor vehicle equipment to reduce risk of death, injury and damage to property and the environment.

Side-impact standard Safety standard developed by authorities for broadside crashes.

1. European side-impact standard Requires cars to protect their occupants when hit in a crash test by an aluminum sled that simulates a car weighing one ton. Top edge of the sled is 31.5 inches high.
2. US side-impact standard Requires cars to protect their occupants when hit in a crash test by a sled that simulates a mid-sized sedan weighing a ton and a half. Top edge of the sled is 33 inches high.
3. Side-standard controversy Concern over the inadequacy of the US standard, at least one third of private vehicles are sports utility vehicles, minivans and pickup trucks which weigh at least 2 tons. Furthermore, the front end heights of these vehicles are from 40 to 49 inches, the bumpers passing clear over a car’s underbody and hitting only the weaker doors.

Crash test Simulated car accident to obtain impact statistics.

1. Oblique crash test Two cars collide at right angles to one another as opposed to head-on. Test is more representative of common passenger car accidents as most collisions occur at some kind of angle.

Crash-test dummy Devices to measure the impact on the human body of car crashes.

1. Parachute man (AmE) Crash-test dummy built in 1946 to test ejection seats for new jet aircraft.
2. Hybrid I Crash-test dummy built by General Motors in 1971, which GM made available to the entire industry.
   1. Anthropomorphic test device GM’s term for crash-test dummy.
3. Hybrid III Crash-test dummy built by General Motors in 1976, which ultimately became the Federal standard after 1 September 1997.
4. Side-impact dummy (SID) (AmE) Test instrument for broadside crashes.
5. EuroSID European side-impact dummy.
6. BioSID Biofidelic side impact dummy.
   1. Biofidelic Close mimicry of the human body.

Zero accident car Program to limit the potential for accidents by SAAB such as the active throttle, 2001.

1. Active throttle System that adjusts the throttle to go no faster than the posted speed limit, developed by SAAB.
2. Alcohol tester Sensor to detect alcohol in a car and the driver has to blow into a breathalyzer to release an ignition interlock.