An actuator assembly is provided that includes a body portion, a first
actuator arm assembly, a second actuator arm assembly, a first flexure
assembly, and a second flexure assembly. Each of the first and second
actuator arm assemblies projects from the body portion and has a distal
end with different respective first and second mechanical configurations.
Each of the flexure assemblies is respectively mounted to the distal ends
of the first and second actuator arm assemblies. The first and second
mechanical configurations are selected to provide the first and second
flexure assemblies with different mechanical resonance characteristics.
In a preferred embodiment, the second actuator arm assembly includes an
actuator arm and a spacer disposed between the actuator arm and the
second flexure assembly. The spacer has a stiffness different from the
stiffness of the actuator arm.