近十年來，協作型機器人（collaborative robot）挾著低成本、輕量化以及高彈性等優勢，逐漸地在中小企業間受到矚目，對規模不大的產線來說，人機協作提高了產線變更的彈性以及舒緩土地和生產成本。由於協作型機器人的實務導入仍在成長階段且須直接與作業員接觸，上線前的評估¬¬－包含與作業員的互動方式和安全議題－也就更為重要。針對產前評估，虛擬製造（virtual manufacturing）為一項整合製程資訊來模擬真實生產的手法，但由於過去多著重於製程、動線等規畫，未將機器人與人員的互動列入考量，因此本研究欲探討能否透過虛擬實境技術來模擬人機協作的互動，以達成上線前的虛擬評估。
本研究招募30名研究參與者，考量可用設備資源的限制，使用綠野仙蹤法（Wizard of Oz Test），由實驗人員在後端操作多關節量測手臂FARO Arm，使參與者在「自認正和自動化機器人互動」的情形下共同進行遞交作業。除了上述的實體互動外，也使用HTC Vive搭配Unity 3D建置與真實場景相同的虛擬環境，讓參與者在沉浸式虛擬環境中與虛擬機器人進行協同作業，並另外針對與虛擬物體的接觸增加聽覺回饋、視覺回饋、聽覺和視覺回饋並存以及觸覺回饋等四種情境，加上接觸時無額外感官回饋的虛擬場景以及實體互動，共有六種情境相互比較。
本研究依體驗者在虛擬環境中自覺是否真實的訊息處理流程，探討認知層面之差異，再比較情境間是否有動作反應的不同，進而影響任務績效。首先透過臨場感問卷和模擬器動暈症問卷探討參與者在不同情境下是否有認知層面的差異，並蒐集研究參與者肩、肘、腕等關節座標與角度後，利用關鍵影格的篩選和主成分分析降低資料維度，再使用集群分析找出與機器人協同遞交的動作策略來探討情境間的動作差異；最後透過量測任務完成時間與正確率，來探討認知與行為的差異是否反映於任務績效。
研究結果顯示，雖然在虛擬場景下參與者具備相當的臨場感，也認為自身在當下是和機器人進行協同作業，但動作策略仍與真實環境相異。此外，提供觸覺回饋的作業模式不只對於臨場感的提升較有助益，還能讓任務績效接近真實環境的表現。基於以上成果，本研究建立一套以虛擬實境技術模擬人機協作的系統與方法，進而提供發展人機協作評估的替代方法之參考；然而，若欲開發人機協作的沉浸式虛擬訓練系統，本研究建議除了考量臨場感外，還要確保虛擬環境下的動作能夠與真實環境一致，方能使虛擬實境模擬的效果貼近實體作業。

Over the past decade, collaborative robots that allow concurrent work with operators in a shared workspace have been gradually adopted in production lines, especially among medium-sized companies. It brings about higher flexibility and lower cost than traditional industrial robots. However, the direct interaction with human operators also raises more concerns of safety issues. So, the evaluation prior to the introduction is considerably important. Virtual manufacturing, a technique applied to production development through virtual simulation, is a common method to evaluate equipment and layout. Nevertheless, the interaction between human operators and robots had not been discussed much in related studies. Hence, the feasibility of simulating human-machine collaboration via virtual reality techniques will be investigated in this study.
30 participants were recruited to collaborate on a hand-over task with a collaborative robot in real and virtual environments. Considering the restriction of experimental environment, the Wizard of Oz experiment method was taken in the real environment condition. A FARO Arm controlled by the test giver was used to pretend that a collaborative robot was interacting with the participant automatically. Besides, a virtual experiment scene was built by using Unity. Participants wore a head mounted display (HTC Vive) and interacted with the Immersive Virtual Environment (IVE). There are six scenarios included in the experiment: real environment, IVE, IVE with haptic feedback for contacts, IVE with auditory feedback for contacts, IVE with visual feedback for contacts, and IVE with both auditory and visual feedback for contacts. It was aimed at not only investigating the difference between real and virtual environments in human-machine collaboration, but finding a more suitable method for such virtual simulations.
The process of information processing that users in virtual reality perceive the reality of environment was taken reference in this study. The difference of cognition among scenarios was discussed in the beginning, and then changes of motions among scenarios and task performance were measured and analysised. At first, presence questionnaire and simulator sickness questionnaire were used to compare the cognition among scenarios. Then, the joint coordinates and angles of shoulders, elbows and wrists were captured by a motion capture system. Considering the dimension of dataset, several key frames that best represent consecutive motions were selected to conduct Principal Component Analysis (PCA). The results of PCA were inputed to conduct cluster analysis to identify different motion strategies performed by participants. At last, task completion time and correct rate were measured to investigate if the difference of cognition and behavior influence participants’ performance.
According to the results of questionnaires, participants consider themselves collaborating with a automated robot and perform high sense of presence. Nevertheless, differences of motion strategies between real and virtual environments were found in collaborative operations. Besides, participants in IVE with haptic feedback perform better sense of presence and similar task performane with real environment. Based on the results, an immersive virtual simulation system was built to evaluate human-machine collaboration, as well as providing recommendations for reference. The findings form this study suggest that not only sense of prence in virtual environment but also the consistence of motions between real and virtual environment should be considered to make the simulatiom more realistic when developing an immersive virtual training system for human-machine collaboration.

摘要
目錄
圖目錄 vii
表目錄 ix
第一章 緒論 1
　　1.1 研究背景與動機 1
　　1.2 研究目的與範圍 3
　　1.3 研究架構與流程 4
第二章 文獻回顧 8
　　2.1 人機協作 8
　　　　2.1.1人機協作的定義與發展 8
　　　　2.1.2人機協作的安全議題 10
　　　　2.1.3人機協作應用領域與評估 13
　　2.2 虛擬實境的模擬與評估 15
　　　　2.2.1 虛擬實境 15
　　　　2.2.2 虛擬實境於產線評估之應用：虛擬製造 16
　　　　2.2.3 虛擬實境於人機協作之應用 17
　　2.3 臨場感 18
　　　　2.3.1 臨場感的影響因素 18
　　　　2.3.2 臨場感評估方法 20
　　2.4 動作策略分析 22
　　　　2.4.1 資料蒐集 22
　　　　2.4.2 資料分析 23
　　2.5 小結 24
第三章 研究方法 26
　　3.1 研究規畫與準備 26
　　　　3.1.1 研究參與者 26
　　　　3.1.2 實驗儀器與設備 26
　　　　3.1.3 實驗場景 29
　　　　3.1.4 作業內容 31
　　3.2 實驗因子 35
　　　　3.2.1 自變數 35
　　　　3.2.2 依變數 39
　　3.3 實驗流程 45
　　3.4 資料分析 48
　　　　3.4.1 動作策略分析 48
　　　　3.4.2 問卷分析 52
　　　　3.4.3 任務績效 53
第四章 研究結果 54
　　4.1 前置作業 54
　　　　4.1.1 在真實場景對於機器人的相信程度 54
　　　　4.1.2 因模擬器動暈症造成的不舒適度 55
　　　　4.1.3 臨場感問卷構面之驗證與定義 64
　　4.2 主動作業模式 68
　　　　4.2.1主動模式下的自覺臨場感和相似度 68
　　　　4.2.2 主動模式下動作策略 74
　　　　4.2.3 主動模式下的任務績效 86
　　4.3 被動作業模式 88
　　　　4.3.1 被動模式下的自覺臨場感與相似度 88
　　　　4.3.2 被動模式下的動作策略 93
　　　　4.3.3 被動模式下任務績效 102
　　4.4 小結 104
第五章 討論 105
　　5.1 虛擬情境下感官回饋對於臨場感之影響 105
　　5.2 不同動作策略間的異同 108
　　5.3 任務績效 112
第六章 結論 113
　　6.1 主要發現 113
　　6.2 研究貢獻與應用 114
　　6.3 研究限制與未來方向 115
參考文獻 118
附錄一：臨場感問卷 127
附錄二：模擬器動暈症問卷 128
附錄三：研究倫理審查核可證明 129

中文部分：
1. 104人力銀行（2016）。104職務大百科。取自https://www.104.com.tw/jb/jobwiki/jobCatMaster/stage/2010001002/4。
2. 李佩蓉（2010）。消費者在虛擬實境中的臨場感體驗與沉浸傾向之研究: 以商業動感模擬遊戲機為例。國立交通大學經營管理研究所碩士論文。
3. 何嘉芬（2017）。人機協作環境中遞交作業等候時間之評估。逢甲大學工業工程與系統管理學系碩士論文。
4. 單萱（2017）。人與機器人組裝協作環境下遞交空間位置及機器人路徑對遞交作業績效之影響。逢甲大學工業工程與系統管理學系碩士論文。

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