The conventional development of tubular generators for applications intended to harvest energy using vehicle suspension systems is faced with the critical challenge of increasing the power harvested for a given space. Conventional optimal designs of machine dimensions have improved both output power and output power density, but the actual values are still relatively small. Recently, we proposed a novel tubular generator structure that combines a mechanical shock absorber and an electrical generator. An innovative permanent magnet structure using both Halbach array and iron spacers (a hybrid-type) was applied. The high relative permeability of the iron material significantly improved the performance of the proposed generator in comparison with conventional models. A prototype was fabricated and experimentally validated via simulation.