No abstract

This study produces an image of theoretical and experimental case of high loading stumbling condition for hip prosthesis. Model had been studied namely Charnley. This model was modeled with finite element method by using ANSYS software, the effect of changing the design parameters (head diameter, neck length, neck ratio, stem length) on Charnley design, for stumbling case as impact load where the load reach to (8.7* body weight) for impact duration of 0.005sec.An experimental rig had been constructed to test the hip model, this rig consist of a wood box with a smooth sliding shaft where a load of 1 pound is dropped from three heights.The strain produced by this impact is measured by using rosette strain gauge connected to Wheatstone bridge for the model .The signal is amplified and sent forward to a data acquisition and then saved in the connected laptop. From this study it is found that the changing in stem length had large effect on effective stress where the change in effective stress while stem length increased from (110mm to 140mm) was not more than (209MPa).

Vibration of some structures might be accepted under restricted limits depending on their design, application and many other factors. Aircraft wing is a structure need to be stable as possible, but there are many disturbances act on wing, so using of active vibration control for vibrated wing can serve to eliminate or suppress the major amount of wing oscillation. In the present work, direct acceleration feedback method is utilized to be used as a controlling technique to satisfy wing stability. Numerical model was simulated in ANSYS environment where the controlling method was totally integrated to generate necessary actuation voltage to derive piezoelectric actuators based on acceleration feedback. Six piezoelectric transducers were modeled in ANSYS by using element SOLID5. Experimental part includes manufacturing (1:6) scaled aircraft wing with two boxes inside and equipped with six piezoelectric transducers worked as sensor/actuator besides labview software inside which the controlling loop was integrated. Modal analysis was performed for numerically simulated model and includes the first six modes of vibration. Free and controlled responses of the tested wing were presented for numerical and experimental model. Results show high degree of agreement between experimental and numerical models. Results show that utilizing the acceleration feedback method for active vibration controlling method can suppress wing vibration and that will pave the way for further application of this controlling method.