טכניון מכון טכנולוגי לישראל
הטכניון מכון טכנולוגי לישראל - בית הספר ללימודי מוסמכים  
M.Sc Thesis
M.Sc StudentShalev Ariel
SubjectVibration Absorption and Damping in a Recoiling System
Mounted on a Moving Platform
DepartmentDepartment of Mechanical Engineering
Supervisor Professor Oleg Gendelman
Full Thesis text - in Hebrew Full thesis text - Hebrew Version


Abstract

In recent years there has been a rapid rise in the amount of autonomous weapons systems used by bodies around the world. This research thesis was requested by the Iftah unit of the IDF, in order to address a design issue found in autonomous weapons systems. Autonomous semi-automatic weapons which were mounted on vehicles were found to get stuck at times, leaving the system unable to fire. As part of this research thesis an analytical model of the aforesaid system was built, and analyzed it in order to identify the cause of the problem. The problem was found to be caused by the vibrations and shocks transferred to the weapon through the moving platform (In this case - a moving robotic vehicle). After the cause of the problem was identified, the design of an appropriate mounting was explored. Using a sample set-up and experimental results of the vibrations of a specific vehicle, algorithms which numerically simulate the weapon’s reaction to the vibrations were written. These simulations centered on analyzing the transient response of the system to a combination of both shock inputs (Caused by the firing of the weapon) and complicated vibration functions (Caused by the vehicles movement). Using these algorithms, different combinations of the stiffness coefficient (K) and the dampening coefficient (C) were tested until the optimal range of variables was found. These coefficients were found to filter out the dangerous frequencies in all the various test runs and driving conditions. In addition to exploring the effect of the frequencies and amplitudes on the transient response of the system, the effect of the phase was also explored. Using the optimal coefficients as design parameters in the weapons-mount prevents the recurrence of weapon faults.

The results of this thesis were verified by the design of the “Tanin” system at Iftah, whose parameters conform to the required coefficients found through the analytical study and analysis of the system.

The program developed as part of the thesis can be used for other systems as well with different parameters and vibration profiles, allowing for the faster and more reliable design of mounting systems - something quite critical for short term design as required in some units of the IDF.