Triax 2015 User Manual page 5

Internal to the head form is a tri-axial sensor (accelerometer) which produces electrical
signals proportional to the G value of the head form's impact with the surface being
tested. Circuitry inside the head form measures these voltages, calculates Peak G, HIC,
impact angle and impact velocity and wirelessly transmits the results to the hand held for
display. Affixed to the head form is a normally on electromagnet. This magnet allows the
head form to be suspended from the lifting cable of the tripod, allowing the user to set
exact drop heights above the surface to be tested. The normally on nature of the
electromagnet requires no battery power to be used while the user prepares for the test
preventing the head form from falling unexpectedly should the batteries grow weak.
CAUTION: To prevent injury never allow any person to stand beneath the missile
when it is suspended from the tripod, nor anywhere in the possible drop path of the
missile.
The head form is powered by an internal rechargeable NiMH battery. Nickel Metal
Hydride (NiMH) batteries are of a lower power density than Lithium Ion batteries thus
allowing the Triax system components to be transported by aircraft if required. Typical
battery life on a full charge exceeds two months of substantial daily use.
The Tripod is used to support the E missile and provide a repeatable drop height and drop
location. A steel cable is used to support a steel block to which the E missile's
electromagnet is attached. The height of the missile above the surface can be adjusted by
lowering or raising the steel block by adjusting the position of the steel lifting cable.
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