Generation and use of mechanical step transients in dynamic measurement

An obstacle to the analysis and synthesis of dynamically loaded structures is the difficulty of measuring the lumped mechanical circuit constants over a sufficiently wide frequency band. This article describes a technique for measuring the wide frequency band mechanical impedances of small structures utilizing a Hopkinson pressure bar. One of the difficulties in using a Hopkinson pressure bar is to obtain absolutely plane contact between the plane ends of the impacting bars. Effective means of achieving this are described.