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In traditional internal combustion engines, a camshaft acts on the valve stems to open and close the valves. Valve timing is fixed relative to piston position. On the other hand, if a valve is flexibly controlled by a variable valve actuation (VVA) system, we can achieve significant improvements in fuel efficiency, engine performance, emissions, etc. One of the most advanced variable valve actuation systems is the VVA operated by an electromechanical actuator without a camshaft, the so-called bi-positional electromechanical valve drive (BPVD). Existing BPVD's characteristically use a spring to provide the required mechanical power for operating a valve. The use of a spring provides many benefits to the design of the system, but it also results in difficult design challenges.