應用PIC微控制器與渦電流感測器之硬幣辨識技術

Coin validation module of application in PIC microcontrollers combine eddy current sensor

康峻菁(Chun-Ching Kang)

指導教授 ： 呂志誠

國立臺北科技大學/機電學院/機電整合研究所/碩士(2013年)

https://doi.org/10.6841/NTUT.2013.00667

摘要

本篇論文延續先前以渦電流感測器方法來辨識硬幣真偽的研究成果，採用PIC18F4525單晶片全面改良做為運算及控制單元，無需使用電腦介面及DAQ，經由撰寫程式，具有學習以及辨識模式。整個系統包含一組模擬投幣機構、一組控制面板、兩組渦電流感測器及硬幣辨識程式。程式撰寫是以Microchip公司開發的晶片編譯器C18系列 ，使用類C語言來撰寫。於PIC晶片中計算出硬幣的感測值，通過USART回傳到電腦終端機顯示，經由大量的真幣學習模式，使晶片內組成硬幣的電壓分布地圖，而當系統切換成辨識模式時，晶片會藉由電壓分布地圖做出判斷，進而辨識出落點在地圖外的偽幣。其中，以同系統中取雙點電壓的差值做為電壓分布地圖之元素，可以建構補償環境溫度影響之能力，使系統更加穩定，能夠以較低的門檻值達到與先前的研究成果。而系統的控制面板可以在執行過程中做出各種指令，如模式切換、取硬幣電壓範圍、顯示硬幣數量、顯示電壓範圍初值、顯示晶片內記取的硬幣地圖、資料記憶體燒入程式記憶體等，更加增進了本研究成果，未來成功商品化的可能性。

關鍵字

PIC微控制器 ； 硬幣辨識 ； 渦電流

並列摘要

This study is continuous work of previous studies using Eddy current sensors to identify the legal coins, and then improves computing and control methods by using single-chip PIC18F4525 with learning and recognition modes. The entire system consists of a set of analog ous coin mechanism, a control panel, two sets of Eddy current sensors and coin validation program. C language is used to program the chip compiler C18 series developed by Microchip. PIC chip can calculate sensing value of coins, and return through USART by showing results on computer terminals, learning through a large number of coins, which constituted into the wafer map, when the system is switched to the identification mode, the chip will judge the coins by the map, thus excluding the impact point on the map outside of the coins. Among them, we take the same system as the voltage difference between the voltage at the point of the element distribution maps, ambient temperature compensation can be constructed influence the ability to make the system more stable, able to lower the threshold value is reached with previous research. The system's control panel can be made in the course of various commands, such as mode switching, take coins voltage range, show the number of coins, display voltage range start value, the coin shows the chip remember map data memory burned into the program memory and so on, more enhanced results of this research, the future success of commercialization possibilities.

並列關鍵字

PIC microcontroller ； Coin validation ； Eddy current

參考文獻

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