在以慣性為基礎的絕對運動追蹤系統中，移動和旋轉的速度及位移是由加速度與時間一次及二次積分計算得到，因此任何錯誤和不確定性都具有累積性。在一個透過無線方式傳輸加速度數值的系統中，封包遺失會隨著時間造成錯誤累積。在這篇論文中，我們提出EcoGinie，一個在動作辨識系統內、特別為無陀螺儀慣性測量儀所設計的封包遺失回復機制。它利用了無陀螺儀慣性測量儀之微控制器和軟體，實做出節點積分技術，幫助恢復遺失的數據。此外，EcoGinie也引入了前向錯誤訂正(Forward Error Correction)的概念，在封包內增加了冗餘，提供錯誤修正的能力。我們模擬了封包遺失的環境，並且用各種遺失率評估了兩種遺失模式；隨機以及突發數據遺失，實驗結果證明EcoGinie有效地將線性運動內因封包遺失造成的錯誤回復，尤其是突發數據遺失發生在動作發生瞬間的效果最佳。

In inertia-based absolute motion tracking systems, the linear and angular velocities and displacements are calculated from integration and double integration of acceleration data over time, respectively. Therefore, any errors and uncertainties of the process are cumulative. In a system where acceleration is transmitted wirelessly, packet loss results in rapid error accumulation over time. In this thesis, we present EcoGinie, a packet loss recovery scheme designed for gyrofree inertial measurement unit (GF-IMU) in motion tracking applications. It performs on-node integration that utilizes the MCU and software of GF-IMU and to help recover the data from lost packets. Furthermore, EcoGinie also incorporates the idea of Forward Error Correction (FEC) and adds redundancy in the packets to enable the host to correct errors. We simulate the packet loss environment and evaluate two kinds of packet loss pattern: random and bursty packet loss with various packet loss rates. The experimental results show EcoGinie recovers from the tracking distortions in linear motion especially when bursty loss happens at the moment the motion occurs.

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