"Jerk"-The Third Derivative


This paper presents raw data, experimentally obtained, on a known function, "Jerk". While the "Jerk" is most commonly seen in introductory Calculus texts as the third derivative, it is most commonly known to have been previously determined empirically.

To investigate this elusive function, raw data was collected using triaxial accelerometer which was attached to a piece of Kevlar webbing, a process which can be best described to the layperson as "bungee jumping" with an inelastic cord. Initial findings from this experiment will be presented.


The "Jerk" is a function defined as the rate of change of acceleration with respect to time. A literature search on the "Jerk" was constructed under the constraints of the availability of resources. The literature search lead a path in the direction of experimentally obtaining the characteristics of the function, "Jerk".

A specially designed apparatus containing a mounting assembly, an EDR-1, and a test bridle was used to gather the raw data required to study the characteristics of the unknown function, "Jerk". This complete assembly was attached to an I Beam located in the ceiling of a building. By attaching the assembly to the ceiling it enabled the apparatus to free fall until its full length was achieved, thus causing a " Jerk".

The raw data obtained from the free fall of the apparatus contains graphs of the triaxial acceleration. This experimental data acquired from the drops will be analyzed in the future to study the characteristics of the "Jerk".

Literature Review:

A literature search was conducted under the restrictions of the accessible resources. According to the literature search, there was very little known concerning the effects of the finite values of a "Jerk". Several theoretical papers were located and revealed very little, if any, useful information. The insufficient applied data, obtained from papers, could not even agree on a proper name to describe the "Jerk". Some expressions used to describe this phenomenon include snap, pulse, bounce, and super acceleration. The only agreement found in the literature was the definition of displacement and is expressed as d3x/dt3. The "Jerk" has importance because it is the measure of the rate of change of acceleration producing a Force. To minimize the effects of the "Jerk", there should be no abrupt changes in the acceleration diagram. Since little data is available, designers have to greatly "boiler plate" or over design to compensate for the effects of the "Jerk".

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