BALL ARM

The Ball Arm is the piece that contains the accelerometer that calculates the speed of the impact. It is locked in place between the clamp and the head form.

The Ball Arm has been custom designed for our helmet testing machines. If you desire a custom design for use with another machine please provide the following information with your order.

The angularity of the arm refers to the drawing measurement C. The different angles most commonly used are 20°, 25°, 30°and 35°. The length of the arm refers to the drawing measurement A. The diameter of the arm refers to the drawing measurement B. Material requested (see below).

The ball arm can be made of three different types of materials to reach different weights depending upon the configuration of your drop assembly. Aluminum: approx 600 grams Stainless Steel: approx 1585 grams Magnesium: approx 375 grams

Description A E J M O Spherical-Impactor Head Form size 1820 2415 3100 3130 3200 3100 Clamp 758 1173 488 458 388 488 4 bolts 82 82 82 82 82 82 Accelerometer kit 10 10 10 10 10 10 Drop Follower / Flying arm 730 730 730 730 730 730 Aluminum Ball arm 0 590 590 590 590 590 Stainless steel Ball arm 1600 0 0 0 0 0 Magnesium Ball arm 0 0 0 0 0 0   Total 5000 5000 5000 5000 5000 5000 Standard Request(total drop mass) 5.0±0.1 5.0±0.1 5.0±0.1 5.0±0.1 5.0±0.1 5.0±0.1

4 bolts: Are used to secure the clamp to the head form. Only 5/16 NC 18 - 1 3/4 inch length bolts should be used to avoid any damage to the tread in the head form. Accelerometer kit: Consists of the accelerometer sensor, support bed, cable. Drop Carriage / Flying arm: The drop guiding system on the machine that will maintain the head form and other parts of the drop assembly in the trajectory of the impact. Ball Arm: The Ball Arm contains the accelerometer sensor and is the moving joint connected to the head form. It allows for various positioning of the head form.