What are Anthropomorphic Test Devices (ATDs) used in car crash tests?
Anthropomorphic Test Devices (ATDs), commonly called crash test dummies, are scientifically designed human-like mechanical devices used in automobile crash tests to study the effects of collisions on the human body. The term anthropomorphic means having human form and characteristics. ATDs replicate human body size, weight, joint articulation, posture, and mass distribution, allowing engineers to realistically simulate how a human occupant would respond during a crash. Each ATD is fitted with numerous sensors and accelerometers in critical body regions such as the head, neck, chest, pelvis, and legs. During a collision, these sensors record forces, accelerations, and deflections, which are then used to calculate injury parameters like Head Injury Criterion (HIC), chest compression, neck loads, and femur forces. Since testing on real humans is impossible for ethical and safety reasons, ATDs provide a reliable, repeatable, and standardized method for evaluating vehicle safety.
ATDs are used to assess the effectiveness of seat belts, airbags, vehicle structures, crumple zones, and interior design. Because they provide consistent results under identical test conditions, ATDs help manufacturers compare different designs and improve occupant protection. The data obtained from ATDs is also essential for regulatory approval and safety ratings, ensuring that vehicles meet prescribed injury limits. Crash tests using ATDs typically last only 100–150 milliseconds, yet within this short time, the dummy records thousands of data points, making it possible to analyze injury risks with high precision.
There are several types of ATDs, each representing a specific category of vehicle occupant. The 50th percentile adult male dummy represents an average adult male and is the most commonly used. The 5th percentile adult female dummy represents a smaller adult, important for evaluating gender-related safety differences. The 95th percentile large male dummy represents a tall and heavy occupant, used to test seat strength and restraint limits. Child dummies (such as 3-year, 6-year, and 10-year equivalents) are used to evaluate child seats and rear-seat safety. Together, these ATDs ensure that vehicle safety is assessed for all occupant sizes and age groups, not just one body type.
