Knees and knee impact test procedure.

§ 572.136 Knees and knee impact test procedure. (a) Knee assembly. The knee assembly (refer to §§ 572.130(a)(1)(v) and (vi)) for the purpose of this test is the part of the leg assembly shown in drawing 880105-560. (b)(1) When the knee assembly, consisting of sliding knee assembly (drawing 880105-528R or -528L), lower leg structural replacement (drawing 880105-603), lower leg flesh (drawing 880105-601), ankle assembly (drawing 880105-660), foot assembly (drawing 880105-651 or 650), and femur load transducer (drawing SA572-S14) or its structural replacement (drawing 78051-319) is tested according to the test procedure in subsection (c), the peak resistance force as measured with the test probe-mounted accelerometer must be not less than 3450 N (776 lbf) and not more than 4060 N (913 lbf). (2) The force shall be calculated by the product of the impactor mass and its deceleration. (c) Test procedure. The test procedure for the knee assembly is as follows: (1) Soak the knee assembly in a controlled environment at any temperature between 18.9 and 25.6 °C (66 and 78 °F) and a relative humidity from 10 to 70 percent for at least four hours prior to a test. (2) Mount the test material and secure it to a rigid test fixture as shown in Figure O5. No part of the foot or tibia may contact any exterior surface. (3) Align the test probe so that throughout its stroke and at contact with the knee it is within 2 degrees of horizontal and collinear with the longitudinal centerline of the femur. (4) Guide the pendulum so that there is no significant lateral vertical or rotational movement at the time of initial contact between the impactor and the knee. (5) The test probe velocity at the time of contact shall be 2.1 ±0.03 m/s (6.9 ±0.1 ft/s). (6) No suspension hardware, suspension cables, or any other attachments to the probe, including the velocity vane, shall make contact with the dummy during the test. [65 FR 10968, Mar. 1, 2000, as amended at 67 FR 46415, July 15, 2002]