具力量感知功能的智慧刀把

Abstract

因應工業4.0與智慧自動化的時代，在工具機加工廠中加裝適當的感測器來及時監測加工品質與效率使加工業能邁向精密化、高速化之目標。本論文旨在研發一款能直接量測到加工時產生的切削力訊號的無線傳輸切削力感測器，此款智慧刀把是將切削力感測結構以及藍芽感測模組內嵌於工具機之刀把之中，目標量測之訊號為Fr、Fz、Mz三組切削訊號。感測結構設計的部分藉由材料力學以及靜力學之原理來進行分析與模擬，設計出一款十字樑之感測結構，並利用有限元素法進行已知外力對此感測結構進行應變模擬分析，結合應變規為量測元件，選取能量到最大應變量之十字樑的位置。應變規之黏貼方式選用四線式量測，目的為將感測結構上之溫度耦合效應以及其他外在環境之耦合影響消除。再利用應變規之量測原理以及十字樑之感測結構建立一數值模型，能將應變規量測到之電壓變化量轉成切削力訊號。之後設計一款藍芽傳輸之無線感測模組，此款感測模組能將三組類比電壓訊號轉成數位訊號，並藉由MCU內部將電壓訊號轉為三組目標切削訊號，再藉由藍芽傳輸至終端，本研究有兩種終端接收方式，其一為電腦連結藍芽接收器接收藍芽訊號；其二為手機應用程式接收藍芽訊號。將前述之感測結構以及藍芽感測模組內嵌於BT40型號之刀把即為本論文所研發之智慧刀把 ( Smart Tool Holder )。智慧刀把製作完成後透過靜態校準來確定此感測器之功能運作是否正常，對智慧刀把分別施加已知的Fr、Fz、Mz外部負載，透過量測出來的負載訊號來進行智慧刀把之驗證以及解耦的步驟，而後將解耦合矩陣重新寫入感測模組中。在硬體方面，智慧刀把經過性能測試後之結果可達到精度Fr為 ±2.3 N，Fz為 ±1.9N，Mz為 ±0.16Nm；量測範圍Fr為 ±3467.5 N，Fz為 ±7192.3 N，Mz為 ±339.8 Nm；取樣頻率300 Hz；解析度12位元；模組功耗為198.6 mW。最後，將此智慧刀把進行實際的動態實驗，將智慧刀把加裝於CNC銑床工具機量測動態切削訊號，再透過現有之量測切削訊號之動力計之量測訊號進行驗證，以此實現智慧刀把之概念。

In response to the era of Industry 4.0 and intelligent automation, appropriate sensors are installed in tool machine to monitor processing quality and efficiency in a timely manner, enabling the processing industry to achieve precise and high-speed targets. This paper aims to develop a wireless transmission cutting force sensor that directly measures the cutting force signal generated during machining. This smart tool holder handles the cutting force sensing structure and the Bluetooth sensing module embedded in the machine tool. In the machine tool, the target measurement signal is three sets of cutting signals: Fr, Fz and Mz. Part of the design of the sensing structure is analyzed and simulated by the principles of material mechanics and statics. The sensing structure of the cross beam is designed, and the finite element method is used to simulate the strain structure. Combine the strain gauge with the measuring component and select the position of the cross beam to the maximum strain. The strain gauge is selected by four-wire measurement to eliminate the coupling effect of the temperature coupling effect on the sensing structure and other external environments. Then, using the measurement principle of the strain gauge and the sensing structure of the cross beam, a numerical model is established to convert the voltage change measured by the strain gauge into a cutting force signal. Then design a wireless sensor module for Bluetooth transmission. The sensing module converts three sets of analog voltage signals into digital signals and converts the voltage signals into three sets of target cut signals through the MCU. From Bluetooth to the terminal, there are two types of terminal reception methods in this study. One is that the Bluetooth receiver connected to the computer receives the Bluetooth signal; the other is that the mobile app receives the Bluetooth signal. The tool holder embedded in the BT40 model has the above sensing structure and Bluetooth sensing module, and is a smart tool holder developed in this paper. After the production is completed, the smart tool holder determines whether the sensor function is normal through static calibration. The known external loads of Fr, Fz and Mz are applied to the smart tool holder and the smart tool holder is verified by the measured load signal. The decoupling step then rewrites the decoupling matrix to the sensing module. In terms of hardware, the performance test result of the smart tool holder reaching the precision Fr is ±2.3 N, Fz is ±1.9N, Mz is ±0.16Nm; the measurement range Fr is ±3467.5 N, Fz is ±7192.3 N, and Mz is ±339.8 Nm. The sampling frequency is 300 Hz; the resolution is 12 bits; the module power consumption is 198.6 mW. Finally, using this smart tool holder to carry out the actual dynamic experiment, the smart tool holder is added to the CNC milling machine to measure the dynamic cutting signal, and then the signal is verified by the existing cutting signal. Realize smart tool holder concept.