hi,i have created a structure as assembly. now i need to do the modal analysis to determine the natural frequency.for that i used frequency simulation ,and in this i made the top and bottom portion of the structure as fixture connector. but there has some bolt holes to join the sub assemblies to the frame, but the bolt joint is not showing in the connector option of the simulation.all other options like hinge weld etc are there. (during assembly i used coinside and concentric mates for the sub assemblies to join the main  frame)