Cantilevered beams with piezoceramic layers are typically used to generate electrical energy; hence, a base excitation on a harvester is required. This work investigates the use of a link-type mechanism called the Peaucellier mechanism to actuate piezoelectric energy harvesters. The Peaucellier mechanism is known to trace an exact straight line, providing harmonic motion, which is exploited here for exciting a bimorph piezoelectric cantilever beam. To generate the required base excitation, a function generation synthesis methodology for designing a defect-free Peaucellier mechanism driven by a dyad (PMD) is proposed, in addition to an example being provided to confirm the efficacy of the method. The harmonic motion involves two design variables (frequency and amplitude) which are key parameters and can be tuned to generate the required electrical power. It was determined that PMD could excite the energy harvester, generating an electrical power of approximately 4.52 μ W at low frequency. The synthesis generated a mean absolute error of 0.061 m/s2 confirming an excellent match between the points of the input-output and desired acceleration. The results confirm that the Peaucellier mechanism is suitable for the actuation of energy harvesters where parasitic power harvesting is required in different practical applications, including robotics and stationary machines.