落地實驗量測系統開發之探討

Study on the System Development for Drop Test

簡維元(Wei-Yuan Chien)

指導教授 ： 陳夏宗

中原大學/工學院/機械工程研究所/碩士(2001年)

https://doi.org/10.6840/cycu200100389

摘要

摘 要
3C產品設計朝向輕、薄、短、小是未來產業不可避免的趨勢，落地衝擊實驗是評估該產品功能的重要指標之一。以目前業界所使用的衝擊試驗準則，僅對一般產品作概括性實驗規範，對於3C產品而言，並無一詳盡規範要求。另一方面，電腦落地試驗模擬來縮短產品開發時間是未來之趨勢，實際量測與模擬比對相互驗證已是重要課題；本研究建立一套完善之落地試驗量測系統，對於落地角度、系統誤差分析及加速規訊號擷取均作深入探討，並且藉由模擬分析來驗證系統之正確性。
本研究架構一套落地試驗平台，平台是以兩個CCD擷取落地瞬間之影像，並經由電腦影像處理落地之兩個畫面可推導出物體實際落地的空間角度（第三投影角）；由系統畫面擷取的延遲時間所導致之角度誤差合乎ASTM D5276的規範之內。本平台另提供多Channels來擷取落地數據。
為評估系統量測值之正確性，藉由一簡單幾何外型之鐵塊作實際落地測試，其量測之加速度值與ANSYS/ LS-DYNA模擬軟體在相同條件下所分析之數據作比對，以驗證此落地試驗平台之可靠度。
經研究發現衝擊加速規之固定方式會直接影響到量測之準確度；在落下過程中，衝擊加速規之訊號連接線會影響落下之角度，因此，產品的重複性不高；模擬軟體方面，簡單之幾何外型鐵塊量測及模擬可相互驗證，但在較複雜之產品（如手機），其量測與模擬仍有差距有待探討。

關鍵字

落地試驗

並列摘要

Abstract
The 3C product will be developed to be light, thin, short, and small in the future. The drop impact test is one important target to evaluate the function of the products. At the present day, the impact test standard used by the industrial circles could only test the general products. There is no detailed standard for the 3C products. On the other side, using the computer drop test simulation to abbreviate the time of developing the products is the trend in the future. To test and verify the practicing measure and the simulating compare has become an important topic.
This research establishes a consummate set of drop test measurement system in order to approach the drop angles, the errors of the system, and the caught signals of the acceleration. Besides, it will test and verify the accuracy of the system by the simulating analysis.
This research establishes a set of drop test platform. The platform could capture the twinkling drop images by two CCD. Moreover, the computer could deal with the two images captured by the CCD to deduce the actual space angles(the third projecting angles ) of the dropping object. The delayed time caught by the system image causes the errors of the angles in accord with the standard of ASTM D5276. The platform also provides several Channels to capture the drop data.
To estimate the accuracy of the system value, a simple geometry shape iron is used in the drop test. To test and verify the reliability of the dropping test platform, we compare the analyzed data of the measured acceleration value and ANSYS/LS-DYNA simulating software at the same condition.
We find the stationary mode of the impact acceleration would directly influence the accuracy of the measurement through the research. In the process of the drop test, the connected wire of the signal of the impact acceleration would influence the dropping angles. Therefore, the duplicate of the products is low. On the aspect of the software, the measurement and the simulation of the simple geometry shape iron could be tested and verified each other. However, the measurement and the simulation of complex products still appear the difference. There is more space for further study.
measure actually the 3C communication product. There are two sets of CCD used in the system structure of drop test to capture the image in the drop instant of X-axis and Y-axis. We also could calculate the angles of the 3-drop axes by the captured image and measure the acceleration and the weight by shock accelerometer and LoadCell.
With the exception of actually measuring the data, we analyze, compare, and simulate the measured data according to the drop analysis software. We could have more data, which is not easy, or unable captured from the analysis simulating soft.
To maintain the system at a proper accuracy, this research also inquire into the speed of the captured image, and the error of the actually measured data.

並列關鍵字

Drop Test

參考文獻

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