【正文】 .with the sample buy in open shut frequency rate is high ,and if a fast speed electrical machine ring should match close ,fasten tasseled phase can be to get very wide frequency band ,because of the fast speed ring should be good ,dynamic configuration sexual can perturbation resistance can force is powerful .According to the root ,with more than ensemble close and this set of electrical machine control project by tolerance of the quantity and electrical machine speed straight flow of hair ,the exhibitor to adopt the project with a single extremely H type can be changed into change device inverse PWM line speed . photoelectric detection module design The intelligent car was stuck on the black line running on white paper “road”, so this module design need to detect shop on the black rubber belt drive area , including Run straight along the arc district and driving district two area .Because f the black and white paper to light reflection coefficient is different ,can according to receive reflected light .The strength of the judge “road”the black line .this paper USES is simple and practical detection methods, namely the infrared detection method.Infrared detection method ,I use infrared ray in different colors of physical surface with different reflection properties characteristics .In the car driving process Continually to the ground to launch the infrared ,when the infrared met white ground occurs when the reflected light ,aimless and launch packed on the car of receiving tube receiving 。一 設計方案電動車的速度、位置、運行狀況的實時測量，并將測量數(shù)據(jù)傳送至單片機進行處理，然后又單片機根據(jù)所監(jiān)測的各種數(shù)據(jù)實現(xiàn)對電動車的智能控制。由于黑線和白紙對光線的反射系數(shù)不同可根據(jù)接收到的反射光的強弱來判斷“道路”黑線。L9110是為控制和驅動電機設計的兩道推挽式功率放大專用集成電路件，將分立電路集成在單片ic之中，使外圍器件成本降低，整機可靠性提高。光敏電阻的阻值隨周圍環(huán)境光線的變化而變化，當光線照射到白線上面時，光線發(fā)射強烈；光線發(fā)射到黑線上面時，阻值會發(fā)生明顯的變化，將阻值的變化只經(jīng)過比較器就可以輸出高低電平。另外，對于景紅外接收后的編碼信號，本系統(tǒng)設計時運用AT89C52單片微機的外部中斷來接收，信號的下降沿觸發(fā)外部中斷。遙控模塊設計師通過吧紅外接收頭1838的輸出端接到單片機的p32管腳上，然后用萬能遙控器對其進行遙控，接著讓單片機解碼，產(chǎn)生PWM控制信號，通過L298控制電機的轉速，讓小車達到前進、左轉、右轉及停止行駛的目的。循跡模塊設計是通過把左右光電傳感器的輸出端分別接到單片機的P22和P23管腳上，然后通過單片機編程，產(chǎn)生PWM控制信號，通過L298控制電機的轉速，讓校車達到前進、左轉、右轉即停止行駛的目的。紅外反射式傳感器由1個紅外發(fā)射管（發(fā)射器）和1個光電二極管（接收器）構成，紅外發(fā)射管發(fā)出的紅外光在遇到反光性較強的物體后被折回，被光電二極管接收，引起光電二極管光生電流的增大，將此變化轉為電壓信號，就可以被處理器接收并處理。L298N是ST公司的產(chǎn)品，內(nèi)部包含4通道邏輯驅動電路，是一種二相和四相電機的專用驅動器，即內(nèi)含二個H橋的高電壓大電流雙全橋式驅動器，接受標準TTL邏輯電平信號，可驅動46v、2A以下的電機。由于采用的是雙驅動的小車，這部分電路必須能夠輸出兩個不同的電壓值，分別去控制小車的左、右兩個驅動電機，使小車的兩個車輪的轉速和方向相同或不同，從而來控制它的前進和轉彎。根據(jù)以上綜合比較，以及本設計中受控電機的容量和直流電機調速的發(fā)展方向，本設計采用了H型單極型可逆PWM變換器進行調速。本系統(tǒng)以單片機為控制核心，實現(xiàn)電動機的前進、退、左轉和右轉功能。 if Fruit is met black line is absorbed ,and than the infrared cars receiving tube receiving less than signal . signal parative module design This part design USES a LM324 parator ,of sensor signal voltage received pare and amplified ,and will pare the results after Feed to the microcontroller ,used to detect sensor sensitivity ,diagram shown in figure 5 shows .When two sensors simultaneously detect light ,straight forward .When the sensor can’t detect light ,in c