Figure 5.

Wave energy harvesting technology utilizing electromagnetic generator. (a) A ring electromagnetic generator. Reprinted with permission from [48]. (b) A wave energy harvesting system for oscillating buoys based on a spatially double X-shaped mechanism. Reprinted with permission from [49]. (c) Maximum power point tracking control based on inertial force for underwater direct-drive wave energy converter. Reprinted with permission from [16]. (d) An integrated wave energy harvesting system that exhibited both omnidirectionality and high efficiency. Reprinted with permission from [50]. (e) An electromagnetic wave energy harvester based on a highly efficient pendulum mechanism. Reprinted with permission from [47]. (f) An electromagnetic generator incorporating a Halbach array. Reprinted with permission from [51].