Is there place for higher order derivatives in mechanics?

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SUMMARY

The discussion centers on the role of higher order derivatives, specifically the third derivative known as "jerk," in mechanics. While traditional mechanics primarily utilizes first and second derivatives (velocity and acceleration), the inclusion of jerk is crucial for modeling systems that require smooth transitions, such as high-performance servo systems and cam-operated mechanisms. The conversation highlights practical applications where minimizing jerk leads to improved performance and comfort, particularly in automotive engineering and machinery design.

PREREQUISITES
  • Understanding of first and second derivatives in mechanics (velocity and acceleration)
  • Familiarity with the concept of jerk as the third derivative of position
  • Knowledge of mechanical systems and their dynamic responses
  • Experience with control systems in engineering applications
NEXT STEPS
  • Research the application of jerk in high-performance servo systems
  • Explore finite jerk motion profiles in mechanical design
  • Study the impact of higher order derivatives in camshaft-follower analysis
  • Investigate the mathematical modeling of systems incorporating higher order derivatives
USEFUL FOR

Mechanical engineers, control system engineers, automotive engineers, and anyone involved in the design and optimization of dynamic systems requiring smooth motion transitions.

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The building of theoretical mechanics can be constructed using only the first and the second derivatives (those of coordinates in case of kinematics: velocity and acceleration and those of energy in case of dynamics: force and gradient thereof). It is obviously unavoidable if one wants to deal with linear responses. However, it is a feature of mathematical formalism we use.

My question is whether we have any justification or proof that taking into account higher order derivatives do not lead us to deeper levels of understanding mechanics (or may be some other areas of physics whose mathematical description ist based on the 1st and the 2nd derivatives) in general case, at least in principle (it is possible of course to invent a special case where they do play some rôle, but I am not interested here in inventing such cases)?
 
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I have seen the higher derivatives in camshaft - follower analysis. As mentioned in the link provided by jedishrfu.
 
The third derivative of position with respect to time (in other words the first derivative of acceleration with respect to time) is usually called the jerk. When driving a car, for example, you feel acceleration. It might, for example, push you backwards in your seat. If the acceleration is constant in both magnitude and direction, that push that you feel is constant. When the acceleration changes you are jerked around in your seat. The faster you change that acceleration (in either magnitude or direction) the more you are jerked around in your seat.

Want a smooth comfortable ride? Minimize the jerk.
 
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Engineers working high performance servo systems get real good at using jerk. When the control engineer first started up the machine shown in US Patent Application 20120167527, the machine would not run at design speed and many of the parts clanged and banged. The control engineer called an emergency meeting, claiming a mechanical problem. When asked if he had implemented the S-curve (finite jerk) motion profiles, he had not. When he implemented them, the machine ran design speed with no clanging or banging.

Jerk is also important in high performance cam-operated systems, such as in automobile engines.

Generally, jerk must be included in the design of any mechanism where the period of the lowest natural frequency is greater than 5-10% of the fastest move.
 
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