A dummy crash test is a full-scale anthropomorphic test device (ATD) that simulates the dimensions, proportions of body weight and articulation of the human body, and is usually instrumented to record data on ATD dynamic behavior in vehicle impact simulations. Dummy Crash Test is widely used by researchers and car companies to predict biomechanics, power, impact, and human injury in car accidents. This data may include variables such as collision velocity, crushing force, bending, folding, or body torque, and deceleration speed during collisions for use in crash tests. More sophisticated dolls are sophisticated machines designed to behave as human bodies and with multiple sensors to record impact strength; the cost may be more than US $ 400,000.
For the purposes of US regulations and the Global Technical Regulations and for clear communication in safety and seating design, dummies carry specially designated reference points, such as H-points; this is also used, for example, in automotive design.
Crash test dummies remain indispensable in development and ergonomics in all types of vehicles, from car to airplane.
There are many special dolls used for obesity, children, impact ribs, and the impact of the spine. THOR is a very sophisticated dummy because it uses a sensor and has a human-like spine and a pelvis. Specialized puppet classes called Hybrid IIIs are designed to examine the effects of frontal impacts, and are less useful in assessing the effects of other types of impact, such as side effects, rear effects, or rollover. IIIs hybrids use dolls intended for a certain age, for example, aged ten, six years, three years, and adult males.
There are certain testing procedures for Hybrid IIIs to ensure that they get the correct human neck bending, and to ensure that they will react to the accident in the same way as the human body does. Using corpses for this research topic is more realistic than using puppets for physiological reasons, but that raises many moral dilemmas.
Through a moral ethical line, car companies have used human corpses, pigs, and people voluntarily tested for impact. A pig is used specifically for the impact of the steering wheel because they have internal structures similar to humans, and can be easily placed properly through sitting right inside the vehicle. Human bodies along with animals are not personally able to give consent to research studies, although animal testing is not uncommon these days.
There are studies that use certain corpses including stale corpses, and carcasses of children. Also, studies show how carcasses have been used to modify different parts of the car such as seatbelts Each new car is made to provide different structural impacts which gives the conclusion that crash test sounds and dummies will be useful for a long time.
Video Crash test dummy
Histori
On August 31, 1869, Mary Ward became the first recorded car accident victim; the car involved is steam-powered (Karl Benz did not create a gasoline-powered car until 1886). Ward, from Parsonstown, Ireland, was thrown out of a motor vehicle and killed. Thirty years later, on September 13, 1899, Henry Bliss became the first victim of a North American motor vehicle when crashing while stepping out of the New York City trolley. Since then, more than 20 million people worldwide have died from motor vehicle accidents.
The need for a means of analyzing and reducing the impact of motor vehicle accidents on humans was felt immediately after the commercial production of cars began in the late 1890s, and by the 1930s, when cars became a common part of everyday life and the number of motor vehicle deaths increased. The death rate has surpassed 15.6 deaths per 100 million vehicle miles and continues to rise.
In 1930 the car had a dashboard of rigid metal, non-folding steering columns, and prominent buttons, buttons and levers. Without seat belts, passengers in frontal collisions can be thrown into the interior of the car or through the windshield. The vehicle body itself is rigid, and the impact force is transmitted directly to the occupants of the vehicle. Until the late 1950s, car manufacturers in public records said that vehicle accidents could not survive because the force in the collision was too great.
Critical test
Detroit State University of Detroit was the first to start seriously collecting data on the effects of high-speed collisions on the human body. In the late 1930s there was no reliable data about how the human body responds to the sudden force that acts in a car accident. In addition, there is no effective tool for measuring such responses. Biomechanics is a field that is barely in its infancy. It is therefore necessary to use two types of test subjects to develop the initial data set.
The first test subject is a human corpse. They are used to obtain basic information about the human body's ability to withstand cracking and tearing forces that are usually experienced in high-speed accidents. For this purpose, the steel ball bearing is dropped on the skull, and the body is thrown down the unused elevator shaft into the steel plate. Bodies equipped with rugged accelerometers are tied into the car and subjected to direct collisions and vehicle rollovers.
Albert King's article 1995 The Trauma Journal, "The Humanitarian Benefit of Cadaver's Research on Injury Prevention", clearly states the value in human life saved as a result of corpse research. King's calculations show that as a result of design changes implemented until 1987, corpse research has since saved 8,500 lives each year. He noted that for every carcass used, every year 61 people survive by wearing seat belts, living on air bags, and holding on to the windshield.
However, working with dead bodies shows almost a lot of problems when solved. Not only are there moral and ethical issues associated with working with the dead, but there are also research concerns. The majority of the bodies available are older white adults who have died non-violently; they do not represent the demographic cross section of casualty victims. Victims of dead accidents can not be employed because any data that may be collected from the experimental subject will be compromised by previous injuries from corpses. Since no two carcasses are the same, and since each particular part of the corpse can only be used once, it is very difficult to achieve reliable comparison data. In addition, child corpses are not only difficult to obtain, but both legal and public opinion make them ineffective. In addition, because collision testing becomes more routine, suitable bodies become increasingly scarce. As a result, biometric data is limited in breadth and leaning towards older men.
Very little attention has been paid to the study of obesity and car accidents, and it is difficult to get fat dolls for experiments. Instead, human corpses are used. Weight loss is an important factor when it comes to car accidents, and body mass is distributed differently in obese people versus non-obese people. At the University of Michigan, obesity carcasses were tested and compared to non-fat corpses, and they found that obesity carcasses had more injuries in their lower extremities. The researchers also suggest that obese people can be protected by their fat almost causing "cushioning effect".
The use of NDT or Neutral Density Target is implemented inside the brain of the corpse to focus on the impact and separation of the brain and skull. NDT provides detailed observation and allows researchers to see specific areas of the brain after collision stimulation. It also helps build and develop FE models. To measure a neck injury for a three-year-old, the FE model is made. The neck of an original child is interpreted and incorporated into the FE model. There are only a few FE models and they are mostly used through sled tests.
Volunteer test
Some researchers take themselves to serve as crash test dummies. Colonel John Paul Stapp USAF pushed himself over 1000 km/h on a sled rocket and stopped within 1.4 seconds. Lawrence Patrick, a professor at Wayne State University, has about 400 rides on a rocket-sled to test the effects of rapid deceleration on the human body. He and his students allowed themselves to be crushed in the chest with a heavy metal pendulum, which was affected by a pneumatic swivel hammer, and sprayed with broken glass to simulate a window blast. While acknowledging that it made him "a little sick", Patrick said that the research he and his students did was seminal in developing mathematical models that could be compared with further research. But while data from direct testing is valuable, human subjects can not withstand tests that pass a certain level of physical injury. To collect information on the causes and prevention of injuries and casualties will require different types of subjects.
Animal testing
By the mid-1950s, most of the coroner's information testing could provide had been harvested. It was also necessary to collect data on survivability of accidents, research on which the body was inadequate. In concert with lack of carrion, this need forced the researchers to look for other models. A description by Mary Roach of the Stability Car Conference and Eight Stapp's Eight Stapp indicates the direction in which research begins to move. "We saw a rocket-ridden chimpanzee, a bear on the impact swing... We observed a pig, drugged and placed in a sitting position in a swing in the harness, crashing into the steering wheel deeply at about 10 mph."
One of the important research objectives that can not be achieved either with a corpse or a living person is a means of reducing injuries caused by ignition on the steering column. In 1964, more than a million casualties caused by the steering wheel were recorded, a significant percentage of all deaths; Introduction by General Motors in the early 1960s from the folded steering column reduced the risk of steering wheel death by up to fifty percent. The animal subject most commonly used in cabin collision studies is pigs, mainly because their internal structures are similar to humans. Pigs can also be placed in a vehicle with a good approach of sitting humans.
The ability to sit upright is an important requirement for test animals in order for other common fatal injuries among human victims, beheading, can be studied. In addition, it is important for researchers to be able to determine the extent to which cabin designs need to be modified to ensure optimal survival. For example, dashboards with too little padding or padding that are too stiff or too soft will not significantly reduce head injury over the dash without padding at all. While buttons, levers, and buttons are essential in vehicle operation, design modifications will ensure that these elements do not tear or puncture the victim in a collision. Impact of the rearview mirror is a significant incident in frontal collisions; how should a mirror be built in such a way that it is stiff enough to do its job but risk low injury if attacked.
While working with carcasses has caused some opposition, especially from religious institutions, it is accepted reluctantly because those who die, die, do not feel pain, and contempt for their situations deal directly with alleviating the suffering of the living. Animal research, on the other hand, arouses much greater passion. Animal rights groups such as ASPCA are very passionate about their protests, and while researchers like Patrick support animal testing because of their ability to produce reliable and applicable data, there remains strong ethical nervousness about this process. Researchers at the University of Virginia should call the families of the victims and tell them what they use for their loved ones, after getting approval from the family. This seems to reduce ethical dilemmas as opposed to testing in animals, since there is not enough way to get approval to use animals.
Although animal trial data are still easier to obtain than mortal data, the fact that nonhuman animals and the difficulty of using adequate internal instrumentation limit its usefulness. Animal testing is no longer done by one of the major car makers; General Motors suspended direct testing in 1993 and other manufacturers followed soon after.
In 1980, the use of animals such as bears and pigs was tested in a car stimulation collision. This leads to a moral dilemma and not the first time an animal is used in a car crash. In 1978, the University of Michigan Highway Safety Research Institute used baboons to be tested as human substitutes in car crashes. Despite objections to animal cruelty that arise, there is also controversy about how they are similar to humans and can be used as a substitute for enough testing for us. The researchers did not stop stopping the use of baboons because of moral objections, but stopped because they found enough data. Moral input from others and organizations is inconsistent, leading to implications when deciding to ban healthy animals from testing the research. The animals were drugged, so there was no pain on them, but the side effects could not justify this. The General Motors Corporation uses animals for testing, and also suggests that they place the animals under anesthesia and then kill the animals once the tests are completed.
Although the University of Michigan Highway Safety Research Institute does not get bad publicity, it is recommended that this is not the reason why they stopped using baboons. The mission of the University of Michigan is to create a safer car for human use. To achieve this goal, research and testing can not be avoided. The cruelty and moral dilemma of animal testing does not make the researchers still use them as subjects. They reasoned that biomechanical data is required for such experiments, which would lead to safer cars. Years later the animal test stopped and instead the instrumental doll was created for a replacement. In 1978, animals were the only source of the subject that would be a reliable substitute for humans. The disadvantage, even though using an instrumental doll or human corpse, is that the tissue is not alive and will not generate the same response as, for example, living animals. Currently, it is not uncommon to see animals being tested for car accidents due to advances in computers and technology. Nevertheless, it is difficult to use corpses rather than animals because of human rights, and it is difficult to get permission from families, especially with children. Approval for research and testing can only occur if the person responsible for approval is a competent person and a person who also fully understands the research and testing procedures.
Maps Crash test dummy
Evolution of the doll
Sierra Sam and VIP-50
Information obtained from corpse research and animal research has been used in simulacra human development as early as 1949, when "Sierra Sam" was invented by Samuel W. Alderson at Alderson Research Labs (ARL) and Sierra Engineering. Co. to test the ejection seat of the aircraft, flight helmet and pilot belt buckle. This test involves the use of high acceleration of up to 1000 km/h (600 mph) rocket, beyond the ability of human volunteers to tolerate. In the early 1950s, Alderson and Grumman produced dolls used to perform crash tests on both motor vehicles and aircraft. The original "Sierra Sam" is a 95% male doll (heavier and taller than 95% human male).
Alderson went on to produce the so-called VIP-50 series, made especially for General Motors and Ford, but which was also adopted by the National Bureau of Standards. Sierra followed up with a stuffed competitor, a model called "Sierra Stan".
Hybrid I and II
General Motors, who has taken over the urge to develop a reliable and durable doll, found that Sierra's model did not meet its needs. GM engineers decided to combine the best features of the VIP and Sierra Stan series, and in 1971 my Hybrid was born. Hybrid I is what is known as the "50th male" percentile doll. That is, the average model of men is high, mass, and proportion. In collaboration with the Society of Automotive Engineers (SAE), GM distributed this design, and the next 5th female doll, with its competitors.
Since then, much work has been done to create more sophisticated puppets. Hybrid II was introduced in 1972, with increased shoulder, spine and knee response, and tighter documentation. Hybrid II became the first doll to meet American Federal Vehicle Safety Standard (FMVSS) for automotive lapswriters and shoulder straps. In 1973, a 50th percentile man doll was released, and the National Highway Transportation Safety Agency (NHTSA) entered into an agreement with General Motors to produce models that outperformed Hybrid II in certain areas.
Despite the large increase in carcass for standard testing purposes, Hybrid I and Hybrid II are still very rugged, and their use is limited to the development and testing of seat belt designs. It takes puppets that allow researchers to explore strategies for reducing injuries. It was a requirement that prompted GM researchers to develop the current Hybrid line, the Hybrid III family of collision test dummies.
Hybrid Family III
Hybrid III, the 50th 50th man doll that first appeared in 1976, is a familiar collision test doll, and he is now a family man. If he can stand upright, he will have a height of 175 cm (5'9 ") and will have a mass of 77 kg (170 pounds).He occupies the driver's seat at the 65 km/h Insurance Highway Insurance Institute (IIHS) 40 mph) offset the frontal collision test, He joined the "big brother", 95 percent Hybrid III, at 188 cm (6 ft 2 in) and 100 kg (223 lb) Ms Hybrid III was the fifth-largest percentile, at least 152 cm (5 feet) and 50 kg (110 pounds) Three children's Hybrid III pupils representing ten-year-olds, 21 kg (47 pounds) six-year-olds and 15 kg (33 pounds) three-year-old children a very recent addition to the dummy collision test family, because so little hard data is available on the effects of accidents on children and the data is very difficult to obtain, this model is based on most estimates and estimates. The main benefit provided by Hybrid III is an increase neck response on front flexion and head rotation better to simulate humans.
The Hybrid III dolls for three-year-olds, six and ten-year-olds have their implications, and do not produce the same physical outcomes that humans would face with frontal collisions. It was found that when testing a three-year-old Hybrid III doll, it shows that a frontal collision is likely to cause a cervical spine injury. When using data from the real world, the results do not match the Hybrid III stimulus injury. To get around this, THUMS is made which stands for Total Human Model of Safety. This model can be easily connected to the human body anatomically mainly focuses on the human spine when affected. Clinical and experimental trials are more accurate than dummy case studies and more can be implemented with this model. This model is based on men only, and mimics human tissues and organs. This model is accurate for men in the 50th percentile, and it can not be easily associated with a three-year-old when handling a neck and head injury responsible for 57 percent of car crash deaths. In contrast, the FE model can be applied appropriately to this criterion.
Test procedure
Each Hybrid III undergoes calibration before a crash test. His head was removed and dropped from 40 centimeters to test the calibration of head instrumentation. Then the head and neck are connected, moved, and stopped abruptly to check for proper neck flexibility. Hybrids wear chamois leather; knees beaten with a metal probe to check for the right puncture. Finally, the head and neck attached to the body, attached to the test platform and struck hard on the chest by a heavy pendulum to ensure that the ribs curved and flexed as they should.
When the doll has been determined to be ready for testing, calibration signs are tied to the side of the head to aid the researcher when the slow-motion film is reviewed later. The doll is then placed inside the test vehicle, set to a sitting position and then marked on the head and knees. Up to fifty-eight data channels located in all parts of Hybrid III, from head to toe, recorded between 30,000 to 35,000 data items in an accident of 100-150 milliseconds. Recorded in a temporary data repository in the dummy's chest, this data is downloaded to the computer after the tests are completed.
Because Hybrid is a standard data collection tool, every part of a certain Hybrid type can be exchanged with others. Not only can a single doll be tested several times, but if a part has to fail, it can be replaced with a new section. The fully-instrumented doll is worth about EUR150,000.
Positioning and restraint
Children in the age group of three are more likely to have age-related deaths where positioning is important. In some countries, children transition from facing the back of the car to facing forward at this age. A study was conducted on the restraint and placement of three-year-olds. It was concluded that under control and in the front seat had a lower mortality rate than children who were positioned in the back seat but uncontrollable. Security results show that children should be placed in the back seat and under control. It also shows that restrictions have a greater impact on safety than sitting positions. The lap belt used in children will not provide as much security as possible for adults, due to the flexibility of children. Adult seat belts can be more harmful to children than good, which is why children should use Child Abuse Systems instead. This system includes a proper booster seat and belt that meets the criteria of the child including age, weight and height.
Custom doll
Source of the article : Wikipedia
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