隨著低功耗電子裝置與無線感測系統的快速發展，如何在低頻且不規則的環境振動下穩定獲取能量，成為能源擷取技術中的重要課題。在壓電獵能相關研究中，多數文獻著重於透過頻率調諧或共振匹配以提升瞬時輸出功率，相對較少從系統層級探討能量輸出之持續性與運作穩定性。本研究提出一種結合擒縱機構與擺盪磁力激振之壓電獵能器，並建立一套以系統動態模型為基礎之參數化整合設計流程，將低頻、不規則機械能透過儲能與週期釋放機制轉換為穩定之激振，以提升壓電能量轉換效率。
本研究首先建立瑞士擒縱機構之非線性動態模型，並以脈衝微分方程描述擒縱輪、擒縱叉與擺輪於不同運動階段下之交互作用。透過參數化定義幾何與機械設計變數，結合顯著因子篩選方法，系統性分析各設計參數及其交互作用對擺輪動能之影響，據以建立有利於提升擺輪動能之擒縱機構設計準則。進一步建立壓電懸臂樑於自由振動與擺盪磁力激振在次諧波共振條件下之理論模型，並以參數分析方式探討磁鐵配置、激振源尺寸與電阻負載條件對平均輸出功率之影響，作為後續整合設計與實驗驗證之性能評估基準。
依據上述分析結果，本研究建立一套擒縱機構與磁力激振壓電樑之參數化系統整合設計流程。該流程以既定之壓電樑幾何尺寸與材料參數為輸入，首先由其動態模型求得壓電樑之自然頻率，並以此作為頻率設計基準，進而以壓電樑自然頻率之次諧波作為擒縱機構端之設計目標頻率。在此設計架構下，根據擺盪磁力激振之動態模型估算可達之目標輸出功率，並透過等效動態模型與設計條件篩選適當之擒縱機構參數，以完成系統整合與原型設計。
以三組不同激振磁鐵配置進行實驗驗證，實驗結果顯示，所提出之擒縱式壓電獵能器可在無外加電力控制下，藉由擺輪之連續且穩定振盪有效激發壓電樑產生電能。在穩態運轉條件下，其平均輸出電功率皆可達 10 μW 以上，並可穩定維持 30 s 以上，且量測結果與理論模型具有良好一致性；而於完整運作週期（由上鍊至停止，約 60–70 s）內，其平均輸出電功率可達 6–7 μW。此外，以馬達驅動方式於次諧波共振條件下之實驗結果亦驗證理論模型，顯示該系統於長時間穩定激振下，具有良好且穩定之能量輸出能力。
整體而言，本研究之主要貢獻在於：(1) 系統性整合擒縱機構與擺盪磁力激振機制於壓電能源擷取系統中；(2) 建立一套參數化系統整合設計流程，串聯理論建模、參數篩選、實驗驗證與系統實作；以及 (3) 透過原型實驗驗證擒縱式壓電獵能器之可行性，為未來微型化機械式能源擷取系統之設計提供具體且可實踐之工程依據。

With the rapid development of low-power electronic devices and wireless sensor systems, harvesting energy from low-frequency and irregular environmental vibrations in a stable manner has become an important challenge in energy harvesting technologies. In piezoelectric energy harvesting research, most existing studies focus on enhancing instantaneous output power through frequency tuning or resonance matching, while relatively few investigate the sustainability and operational stability of energy output from a system-level perspective. This study proposes a piezoelectric energy harvester integrating an escapement mechanism with oscillating magnetic excitation and establishes a parametric systematic integrated design approach based on dynamic system modeling. Through energy storage and periodic release mechanisms, low-frequency and irregular mechanical energy is converted into stable excitation, thereby improving the efficiency of piezoelectric energy conversion.
First, a nonlinear dynamic model of the Swiss Lever Escapement Mechanism is established, and the interactions among the escape wheel, pallet fork, and balance wheel in different motion phases are described using impulse differential equations. By parameterizing geometric and mechanical design variables and applying significant factor screening methods, the effects of individual parameters and their interactions on the kinetic energy of the balance wheel are systematically analyzed, leading to the formulation of design guidelines for escapement mechanisms that are favorable for enhancing balance wheel kinetic energy. Furthermore, theoretical models of the piezoelectric beam under free vibration and oscillating magnetic excitation under subharmonic resonance conditions are developed. Parametric studies are conducted to investigate the effects of magnet configuration, excitation source dimensions, and load resistance on the average output power, serving as performance benchmarks for integrated design and experimental validation.
Based on the above analyses, a parametric systematic integrated design process for the escapement mechanism and magnetically excited piezoelectric beam is established. The proposed design process takes the geometric dimensions and material properties of the piezoelectric beam as inputs, from which the natural frequency of the beam is first determined using its dynamic model and adopted as the frequency design reference. The target design frequency of the escapement mechanism is then defined as the subharmonic of the beam’s natural frequency. Under this design criteria, the achievable target output power is estimated to be using the dynamic model of oscillating magnetic excitation, and appropriate escapement mechanism parameters are selected through equivalent dynamic modeling and design constraints to complete system integration and prototype development.
Experimental validation is conducted using three different configurations of excitation magnets. The results demonstrate that the proposed escapement-based piezoelectric energy harvester can effectively generate electrical energy through continuous and stable oscillations of the balance wheel without external power control. Under steady-state stage, the average electrical output power exceeds 10 μW and can be maintained for more than 30 s, with good agreement between experimental results and theoretical predictions. Over a complete operating cycle (from winding to stop, approximately 60–70 s), the average output power reaches 6–7 μW. In addition, experiments under motor-driven subharmonic excitation conditions further validate the theoretical model, indicating that the system can deliver stable and relatively high energy output under long-term steady excitation.
Overall, the main contributions of this study are: (1) the systematic integration of an escapement mechanism and oscillating magnetic excitation into a piezoelectric energy harvesting system; (2) the establishment of a parametric systematic integrated design methodology linking theoretical modeling, parameter screening, experimental validation, and system implementation; and (3) the experimental verification of the feasibility of an escapement-based piezoelectric energy harvester, providing practical and implementable engineering guidelines for the future design of miniaturized mechanical energy harvesting systems.

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