恆定侵入準二維顆粒床期間振動對作用力及顆粒動態影響之實驗研究

Abstract

本論文自行搭建伺服馬達與線性滑軌組成的實驗機台，試圖模擬類二維(Quasi-2D)的緊密排列之圓柱顆粒床恆定侵入的情形。 在實驗機台上，作為推進擠壓部件的intruder，由伺服馬達與線性滑軌的組合帶動並向圓柱顆粒堆施以軸向力擠壓，藉此模擬緊密排列之圓柱顆粒床受到外力擠壓的作用力變化情形，同時intruder上安裝了一震動產生器，以觀測在恆定侵入的同時加入外部震動對於緊密排列的圓柱顆粒堆的影響，此現象乃本論文之研究主軸。 此實驗的設置安排即針對此運動與現象進行模擬，透過兩種尺寸的圓柱顆粒在實驗平台上不同的填充分率(Packing Fraction)進行分組的模擬實驗，以不同底床顆粒的擺置條件作為變因，進行無震動的推進擠壓實驗以及有震動的推進擠壓實驗。 量測的部分我們在擠壓部件的後方安裝了一顆六軸荷重元力感測器，用以連接放大器以及PC上的LabView軟體監測擠壓與顆粒回推的力與力矩範圍變化，以及不同底床填充分率造成的力與力矩極值，更可依此判斷加入震動與否對於intruder與顆粒交互作用力變化的影響。在機台正下方安裝的高速攝影機，用以拍攝與捕捉顆粒移動與轉動的影像素材，進行後續的影像處理。利用Matlab測量移動和轉動的影像處理演算法，對於顆粒的位置、角度變化和速度場進行觀測與判讀。 此研究著重於實驗機台的設計與設置，並針對加入震動與否對於恆定侵入緊密排列之顆粒床的力感測結果與影像處理結果有初步的分析和小結，希望此研究之實驗設置與分析可以對未來此領域之研究有所助益。

This thesis presents a custom-built experimental setup consisting of a servo motor and a linear rail to simulate the quasi-2D scenario of constant intrusion into a densely packed bed of cylindrical grains. On the experimental platform, the intruder, acting as a pushing component, is driven by the combination of a servo motor and a linear rail. It exerts axial force onto the bed of cylindrical particles to simulate the force variation experienced by the tightly packed bed when subjected to external compression. Additionally, a vibration generator is installed on the intruder to observe the impact of external vibrations on the densely packed cylindrical particle bed during constant intrusion. This phenomenon is the central focus of this study. The experimental setup is designed to simulate this motion and phenomenon. Simulations were conducted using cylindrical grains of two different sizes with varying packing fractions on the experimental platform. For measurement, a six-axis load cell sensor was installed behind the intruder. This sensor connects to an amplifier and a PC running LabVIEW software, allowing for real-time monitoring and data collection of the force and torque variations during intrusion. It also measures the peak force and torque caused by different packing fractions. This setup enables the assessment of the impact of vibrations on the interaction forces between the intruder and cylinders. A high-speed camera mounted underneath the platform captures images of cylinder movement and rotation, providing data for subsequent image processing. Using MATLAB-based image processing algorithms, we analyze the displacement, angular changes, and velocity fields of the cylinders. This research focuses on the design and setup of the experimental apparatus, along with preliminary analysis of the force sensor results and image processing outcomes concerning the presence or absence of vibrations during constant intrusion into the densely packed granular bed. The findings aim to contribute valuable insights to future research in this field.