Developing a Linear Impactor Test Method for Ice Hockey

摘要

Ice hockey helmets are certified to standards that include drop tests that limit linear acceleration imparted to a surrogate headform. Historically, this test has been successful as a measure of a helmet's ability to absorb energy and mitigate serious to severe head injury. However, new interest in concussions has demanded new test methods to address these brain injuries. Evolving research shows the importance of rotational kinematics in concussion and hence the desire for a rotational helmet impact test. The standard drop test simulates hard, flat surfaces in hockey such as the ice, boards, and glass. However, open ice collisions involving shoulder and elbow impacts are poorly defined in terms of surface stiffness, impact speed, and responding head kinematics. In this present work, we explore the feasibility of measuring these factors directly in a series of on-ice experiments using a Hybrid Ⅲ pedestrian crash test dummy setup to resemble a hockey player. The dummy head was instrumented for linear and rotational accelerations. A special test fixture simulated a realistic hockey posture and head elevation. Two experienced adult male hockey players delivered a series of increasingly aggressive shoulder and elbow strikes to the helmeted dummy head at elevated skating speeds. Results showed that elbow strike acceleration and time duration were similar to a standard drop test at a lower drop height. Shoulder impacts were of longer time duration and could be simulated by a padded strike face added to a linear impactor helmet test apparatus. The linear impactor was set up with the same Hybrid Ⅲ head and helmet from the on-ice experiments. Iterative tests were run to converge on the design of a padded face to match the shoulder response from the on-ice tests. This pilot program was shown to be a feasible approach toward developing a shoulder impact simulator, although limitations are discussed. These on-ice head impact data provide insight into the unique character of shoulder-to-head and elbow-to-head impacts. This new test method may provide a foundation for future ice hockey test standards.