臺灣博碩士論文加值系統

本文提出在G01軌跡中利用FIR濾波器實現急衝度基底之時間最佳化運動軌跡規劃，在滿足機台限制的前提下，使系統能以最佳的效能規劃出滿足轉角誤差限制的軌跡，且以急衝度為基底之後加減速規劃，於轉角處之速度命令、加速度命令以及急衝度命令可保有良好的連續性，此外還擁有速度命令與加速度命令起始值不必為零的優點，本文透過模擬G01軌跡驗證理論，模擬結果顯示系統特性與理論一致且相較於加速度基底能更有效改善加工時間。
對於金屬積層製造採用的是選擇性雷射燒熔技術，其優點是能夠完成高複雜度的工件且應用範圍廣泛，但製程的不穩定性一直是急需克服的難點，為此本文分別提出多底材線寬模型、線高模型與熱堆積模型來改善燒熔結果的一致性及緻密度，透過實驗建立製程參數資料庫並藉由符號回歸方法找出軌跡線寬、雷射功率與掃描速度的關係式，再搭配軌跡線高模型與針對熱堆積區域的能量調整參數，使得實驗結果在軌跡線寬的一致性及層與層之間的孔隙率良好控制，從而滿足成品所需的精度及機械強度。

The study presents that implementing the time-optimal motion planning by jerk-based FIR Filters can be applied to the G01 trajectory. Subject to the constraints, the trajectory profile generated by the method at corner can satisfy the corner error and keep the velocity, acceleration and jerk away from discontinuity. Besides, ADAI based on jerk profile does not limit the initial values of velocity and acceleration must be zero. Make the motion planning become more flexible. The study verifies the method of motion planning through simulating the G01 trajectory, and the properties of results are consistent with the theory. It also reduces the spending time compare with the acceleration-based around 5%.
Selective laser melting is an additive manufacturing method which has the advantage of manufacturing high-complexity workpieces. But the process of SLM is difficult to keep consistent and stable. To solve the problem, the study proposes the model of multi-substrate track width, the model of track height and the model of heat accumulation. The study conducts many experiments with different parameters including the width of melting track, the power of laser and the speed of scanning. The experimental results can be established as databases, then figure out the related equation by using symbolic regression. Besides, applying the model of height and power correction coefficient to the process is useful for improving the consistency of track and porosity.

目錄
摘要 i
ABSTRACT ii
誌謝 iii
第一章 緒論 1
1.1 研究目的與動機 1
1.2 文獻回顧 2
1.3 研究方法 4
1.4 內容大綱 6
第二章 急衝度基底之後加減速運動規劃 7
2.1 急衝度基底之FIR 濾波器速度規劃 9
2.2 轉角的後加減速規劃 11
2.2.1 單一方塊急衝度命令分析 13
2.2.2 轉角分軸急衝度 18
2.2.3 轉角分軸加速度 20
2.2.4 轉角分軸速度 22
2.2.5 轉角分軸軌跡 25
2.3 轉角誤差 28
2.4 G01軌跡運動規劃 28
2.4.1 轉角運動規劃 29
2.4.2 直線段運動規劃 31
2.5 模擬與討論 35
2.5.1 模擬一：偶數長度濾波器 36
2.5.2 模擬二：奇數長度濾波器 38
2.5.3 模擬三：方形軌跡 40
2.5.4 模擬四：鑽石軌跡 43
2.5.5 分析與討論 47
第三章 SLM製程模型 49
3.1 設備系統介紹 49
3.2 多底材軌跡線寬之數據驅動模型 51
3.3 轉角熱堆積區域補償 59
3.4 線高模型 73
3.5 分析與討論 76
第四章 總結 79
4.1 結論 79
4.2 未來展望 80
參考文獻 81
附錄一 製程參數實驗線寬數據 84
附錄1.1 第一層線寬數據 84
附錄1.2 第二層線寬數據 88
附錄1.3 第三層線寬數據 93
附錄二 轉角補償實驗照片 98
附錄2.1 線寬240um 98
附錄2.2 線寬260um 100
附錄2.3 五層薄壁線寬220um 101
附錄2.4 五層薄壁線寬240um 103
附錄2.5 五層薄壁線寬260um 105
附錄三 製程參數實驗線高數據 107
附錄四 Droplet驗證實驗照片 109

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