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1、畢業(yè)論文(設(shè)計(jì))外文翻譯題 目: 關(guān)于單片機(jī)的電動(dòng)智能小車 系部名稱: 專業(yè)班級(jí): 學(xué)生姓名: 學(xué) 號(hào) 指導(dǎo)教師: 教師職稱: 2 年月日基于單片機(jī)的電動(dòng)智能小車通過研發(fā)實(shí)現(xiàn)了一種以光電傳感器為敏感元件,以 at89c51 單片機(jī)為控制核心的電動(dòng)循跡小車的智能控,該系統(tǒng)還包括直流電機(jī)、l9110 芯片和 lm324 比較器等。本設(shè)計(jì)采用 at89c51 單片機(jī)作為智能小車核心控制器。本系統(tǒng)以單片機(jī)為控制核心,實(shí)現(xiàn)電動(dòng)車的前進(jìn)、退、左轉(zhuǎn)和右轉(zhuǎn)功能。通過角度傳感器檢測(cè)蹺蹺板角度的變化,利用增量式 pi算法控制電動(dòng)車尋找平衡點(diǎn),同時(shí)運(yùn)用光電傳感器檢測(cè)黑線,使電動(dòng)車在行駛過程中保持直線運(yùn)動(dòng)且不會(huì)脫離蹺
2、蹺。1方案設(shè)計(jì)電動(dòng)車的速度、位置、運(yùn)行狀況的實(shí)時(shí)測(cè)量,并將測(cè)量數(shù)據(jù)傳送至單片機(jī)進(jìn)行處理,然后由單片機(jī)根據(jù)所檢測(cè)的各種數(shù)據(jù)實(shí)現(xiàn)對(duì)電動(dòng)車的智能控制。這種方案能實(shí)現(xiàn)對(duì)電動(dòng)車的運(yùn)動(dòng)狀 態(tài)進(jìn)行實(shí)時(shí)控制,控制,靈活可靠,精度高,可滿足對(duì)系統(tǒng)的各項(xiàng)要求。(1)直流調(diào)速系統(tǒng)直流調(diào)速系統(tǒng)采用脈寬調(diào)速系統(tǒng),其主電路采用脈寬調(diào)制式變換器,簡(jiǎn)稱pwm變換器。由于pwm調(diào)速 系統(tǒng)的開關(guān)頻率較高,僅靠電樞電感的濾波作用就可以獲得脈動(dòng)很小的直流電流,電樞電流容易 連續(xù),系統(tǒng)的低速運(yùn)行平穩(wěn),調(diào)速范圍較寬,可達(dá)1:10000左右。 由于電流波形比 v-m系統(tǒng)好,在相同的平均電流下,電動(dòng)機(jī)的損耗和發(fā)熱都比較小。同樣由于開關(guān)頻率高
3、,若與快速響應(yīng)的電機(jī)相配合,系統(tǒng)可以獲得很寬的頻帶,因此快速響應(yīng)性能好,動(dòng)態(tài)抗擾能力強(qiáng)。根據(jù)以上綜合 比較,以及本設(shè)計(jì)中受控電機(jī)的容量和直流電機(jī)調(diào)速的發(fā)展方向,本設(shè)計(jì)采用了h型單極型可逆 pwm變換器進(jìn)行調(diào)速。1.1 光電檢測(cè)模塊設(shè)計(jì)該智能小車在貼有黑線的白紙“路面”上行駛,因此本模塊設(shè)計(jì)需要檢測(cè)鋪在行駛區(qū) 的 黑 膠 帶,包 括直線行駛區(qū)和沿弧線行駛區(qū)兩個(gè)區(qū)域。由于黑線和白紙對(duì)光線的反射系數(shù)不同可根據(jù)接收到的反射光的強(qiáng)弱來判斷“道路”-黑線。本文采用的是簡(jiǎn)單實(shí)用的檢測(cè)方法,即紅外探測(cè)法。紅外探測(cè)法,即利用紅外線在不同顏色的物理表面具有不同的反射性質(zhì)的特點(diǎn)。在小車行駛過程中不斷地向地面發(fā)射紅外
4、光,當(dāng)紅外光遇到白色地面時(shí)發(fā)生漫發(fā)射,反射光被裝在小車上的接收管接收;如果遇到黑線則紅外光被吸收,則小車上的接收管接收不到信號(hào)。1.2 信號(hào)比較模塊設(shè)計(jì)輸送給單片機(jī),用于檢測(cè)傳感器的敏感性,電路圖如圖 5 所示。當(dāng)兩個(gè)傳感器同時(shí)檢測(cè)到光時(shí),直線前進(jìn)。當(dāng)傳感器檢測(cè)不到光時(shí),處于截止?fàn)顟B(tài),雙運(yùn)算放大器 lm324 輸出低電平給單片機(jī),由程序處理; 若左路未檢測(cè)到光,則向左糾正方向; 若右路未檢測(cè)到光,則向右糾正方向。1.3 電機(jī)控制與驅(qū)動(dòng)模塊設(shè)計(jì)由于采用的是雙驅(qū)動(dòng)的小車,這部分電路必須能夠輸出兩個(gè)不同的電壓值,分別去控制小車的左、右兩個(gè)驅(qū)動(dòng)電機(jī),使小車的兩個(gè)車輪的轉(zhuǎn)速和方向相同或不同,從而來控制它
5、的前進(jìn)和轉(zhuǎn)彎。在系統(tǒng)的設(shè)計(jì)過程中,用兩個(gè) l9110 芯片來分別連接單片機(jī)和直流電機(jī)。l9110 是為控制和驅(qū)動(dòng)電機(jī)設(shè)計(jì)的兩通道推挽式功率放大專用集成電路器件,將分立電路集成在單片 ic 之中,使外圍器件成本降低,整機(jī)可靠性提高。該芯片有兩個(gè) ttl / cmos 兼 容 電 平 的 輸 入,具 有良好的抗干擾性; 兩個(gè)輸出端能直接驅(qū)動(dòng)電機(jī)的正反向運(yùn)動(dòng),它具有較大的電流驅(qū)動(dòng)能力,每通道能通過800ma 的持續(xù)電流,峰值電流能力可達(dá) 1.5 2.0a; 同時(shí)它具有較低的輸出飽和壓降與靜態(tài)電流; 內(nèi)置的鉗位二極管能釋放感性負(fù)載的反向沖擊電流,使它在驅(qū)動(dòng)繼電器、直流電機(jī)、步進(jìn)電機(jī)或開關(guān)功率管的使用上
6、安全可靠。循跡小車系統(tǒng)以常見的 at89c51 單片機(jī)為核心,輔以較簡(jiǎn)單的元器件和電路設(shè)計(jì),在順利完成循跡功能的前提下,又充分考慮到了外觀、成本等問題,因此小車的大部分電路由手工焊接完成。在設(shè)計(jì)中,我們沒有在電路中增加冗余的功能,但是保留了各種硬件接口和軟件子程序接口,方便以后的擴(kuò)展和開發(fā)。2 系統(tǒng)硬件設(shè)計(jì)2. 1 電機(jī)驅(qū)動(dòng)模塊設(shè)計(jì)在制作智能小車時(shí), 后左、右輪分別用兩個(gè)轉(zhuǎn)速和力矩基本完全相同的直流減速電機(jī)進(jìn)行驅(qū)動(dòng), 車頭前部裝一個(gè)方向輪, 然后通過 i/o 口控制兩個(gè)直流減速電機(jī)的轉(zhuǎn)速和轉(zhuǎn)向就可以實(shí)現(xiàn)小車的左轉(zhuǎn)、右轉(zhuǎn)和直行。電機(jī)驅(qū)動(dòng)采用一片集成電機(jī)驅(qū)動(dòng)芯片l 298n。l298n是st公司的
7、產(chǎn)品,內(nèi)部包含 4通道邏輯驅(qū)動(dòng)電路,是一種二相和四相電機(jī)的專用驅(qū)動(dòng)器,即內(nèi)含二個(gè)h 橋的高電壓大電流雙全橋式驅(qū)動(dòng)器,接收標(biāo)準(zhǔn) ttl邏輯電平信號(hào),可驅(qū)動(dòng) 46v、2a 以下的電機(jī)。2. 2 尋跡模塊設(shè)計(jì)尋跡模塊主要由光電反射式傳感器組成。光敏電阻的阻值隨周圍環(huán)境光線的變化而變化,當(dāng)光線照射到白線上面時(shí),光線發(fā)射強(qiáng)烈; 光線照射到黑線上面時(shí),光線發(fā)射較弱。因此當(dāng)光敏電阻在白線和黑線上方時(shí),阻值會(huì)發(fā)生明顯的變化,將阻值的變化值經(jīng)過比較器就可以輸出高低電平。但是這種方式受環(huán)境影響大,工作不穩(wěn)定。本文實(shí)際采用的是 rpr220 型反射式傳感器制作的尋跡模塊。rpr220是一種一體化反射型光電探測(cè)器,其
8、發(fā)射器是一個(gè)砷化鎵紅外發(fā)光二極管,而接收器是一個(gè)高靈敏度硅平面光電三極管。當(dāng)發(fā)光二極管發(fā)出的光反射回來時(shí), 三極管導(dǎo)通并輸出低電平。2. 3 避障模塊設(shè)計(jì)避障模塊主要由紅外反射式傳感器組成。紅外反射式傳感器由 1 個(gè)紅外發(fā)射管 (發(fā)射器 )和 1個(gè)光電二極管 (接收器 )構(gòu)成,紅外發(fā)射管發(fā)出的紅外光在遇到反光性較強(qiáng)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(zhuǎn)為電壓信號(hào),就可以被處理器接收并處理。2. 4 遙控模塊設(shè)計(jì)本模塊發(fā)射端采用高靈敏的 h l - 5000型萬能電視遙控器, 接收端采用接收頻率為 38kh z的萬能接收頭 1838, 該模塊與單片機(jī)接口非常方
9、便。另外, 對(duì)于經(jīng)紅外接收后的 編 碼 信 號(hào), 本系統(tǒng)設(shè)計(jì)時(shí)運(yùn)用at89c52單片微機(jī)的外部中斷來接收, 信號(hào)的下降沿觸發(fā)外部中斷。為了識(shí)別一個(gè)完整的鍵信號(hào), 必須對(duì)每一個(gè)編碼脈沖的寬度進(jìn)行測(cè)量, 以判別接收到的脈是 0還是 1, 利用單片機(jī)中的定時(shí)器 /計(jì)數(shù)器來測(cè)量脈沖寬度。定時(shí)器 /計(jì)數(shù)器的除分比是可以設(shè)定的, 從除 2到除 2048, 可測(cè)量的脈沖寬度可達(dá) 500m s。本文設(shè)定的除分比為 12, 即 12分頻, 因?yàn)橥獠繒r(shí)鐘約為 12mh z, 時(shí)鐘周期為 1 s, 所以定時(shí)器 /計(jì)數(shù)器每計(jì)時(shí)一次為 1 s。2. 5 報(bào)警模塊設(shè)計(jì)報(bào)警模塊的核心芯片選擇 110報(bào)警 ic,可應(yīng)用于汽車
10、、摩托車、防盜器、個(gè)人防暴器、門磁報(bào)警 器等場(chǎng)所。三 系統(tǒng)軟件設(shè)計(jì)本系統(tǒng)軟件采用模塊化結(jié)構(gòu), 由主程序初始化子程序、中斷子程序、延時(shí)子程序、按鍵發(fā)音子程序、按鍵掃描子程序構(gòu)成。3. 1 尋跡子程序設(shè)計(jì)尋跡模塊設(shè)計(jì)是通過把左 右光電傳感器 的輸出端分別接到單片機(jī)的p2.2和p2.3引腳上,單片機(jī)編程 產(chǎn)生 pwm 控制信號(hào),通過 l 298控制電機(jī)的轉(zhuǎn)速, 讓小車達(dá)到前進(jìn)、左轉(zhuǎn)、右轉(zhuǎn)及停止行駛的目的。3. 2 避障子程序設(shè)計(jì)避障模塊設(shè)計(jì)是通過把左右紅外反射式傳感器模塊的輸出端分別接到單片機(jī)的 p20和 p21管腳上,然后通過單片機(jī)編程,產(chǎn)生 pwm 控制信號(hào),通過 l298控制電機(jī)的轉(zhuǎn)速,讓小車
11、達(dá)到前進(jìn)、左轉(zhuǎn)、右轉(zhuǎn)及停止行駛的目的。3. 3 遙控子程序設(shè)計(jì)遙控模塊設(shè)計(jì)是通過把紅外接收頭1838的輸出端接到單片機(jī)的 p32管腳上,然后用萬能遙控器對(duì)其進(jìn)行遙控,接著讓單片機(jī)解碼,產(chǎn)生 pwm 控制 信號(hào),通過 l298控制電機(jī)的轉(zhuǎn)速,讓小車達(dá)到前進(jìn)、左轉(zhuǎn)、右轉(zhuǎn)及停止行駛的目的。四總結(jié)采用單片機(jī)為核心, 利用光電傳感器和紅外反射式傳感器作為探測(cè)系統(tǒng), 設(shè)計(jì)了可以實(shí)現(xiàn)自動(dòng)尋線行走、自動(dòng)避障、報(bào)警以及遙控等功能的智能小車。該設(shè)計(jì)的顯著優(yōu)點(diǎn)是電路簡(jiǎn)單、可靠性強(qiáng)、成本低, 并且非常易于功能進(jìn)一步完善和擴(kuò)展。本文摘譯自:華東師范大學(xué)電子科學(xué)技術(shù)系科技風(fēng) 2009年10期 作者 于江江 王敬軒 楊豐
12、electric intelligent car based on scm through research and to realize a photoelectric sensor for sensitive components, with at89c51 as control core electric tracing of intelligent control carbonylation-the car,the system is also including dc motor, l9110 chips and lm324 comparator etc. the design us
13、es at89c51 as intelligent car core controller。the system takes microcontroller as control core and realization of electric before enter, back, turn left and right turn function. through the angle sensor 1 detection the seesaw angle change, use incremental pi algorithm 2 to control the electric car f
14、or balance, and using photoelectric sensor detection black line, make the electricity actuation vehicle in the course of driving keep linear motion and dont skip from atrium。1.project designlight by a sensor, the reality of the electric car is moving quickly degrees, bit, buy, transportation line sh
15、ape when measured quantity of real condition, and will be measured quantity number according to preach sent to monolithic machine into line processing, but by single chip machine according to the measured by root different forms of several inspection according to real now to electric actuation vehic
16、le wisdom can control system. this kind of square case can real now to electric actuation vehicle dynamic shape state into the shipment do real possession in system, control system spirit alive, can depend, pure degree is high, can full foot of each item of the stockings to beg. (1) straight epidemi
17、ological speed is tasseled straight epidemiological speed department with pulse width modulation experience.meanwhile gather speed is experience.meanwhile, its main electrical pulse width modulation by road system type variable change device, jane says pwm variable change device. adjustable speed by
18、 in the department of pwm experience.meanwhile open shut frequency rate is high, only on electricity barnado electricity sense of filter wave can be use to get to move very small straight pulse electric flow, electricity flow barnado electric capacity easily even tantras, department of low speed ope
19、ration flat experience.meanwhile, adjustable speed stability van is surrounded relatively wide, can reach 1 000 left right. by on electrical flow wave shape than v - m system, be in phase with flat to all electrical flow dynamic machine, electric heat consumption and hair loss than a small. with the
20、 sample by in open shut frequency rate is high, and if a fast speed of 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 powerf
21、ul. 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
22、 line speed.1.1 photoelectric detection module designthe 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 of the
23、 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.e. use infrared
24、 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 r
25、eceiving; if fruit is met black line is absorbed, and then the infrared cars receiving tube receiving less than signal.1. 2 signal comparative module designthis part design uses a lm324 comparator, of sensor signal voltage received compare and amplified, and will compare the results after feed to th
26、e microcontroller, used to detect sensor sensitivity, diagram shown in figure 5 shows. when two sensors simultaneously detect light, straight forward. when the sensor cant detect light, in cut-off state, double lm324 operational amplifier output low level to microcontroller, by program processing, i
27、f left not detected light, then left correct direction; if the right has not been detected light, then turn correct direction.1. 3 motor control and driving module designbecause use is double drive cars, this part of the circuit must be able to output of two different voltage values, respectively to
28、 controlling trolley right and left two motor drive, the two of the wheel speed and direction of the same or different, thus to control its advance and turning. in system design process, use two l9110 chips to connect scm and dc motor respectively. l9110 is for control and drive motor design two cha
29、nnels push-pull power amplifier application-specific integrated circuit device, discrete circuits in monolithic ic integrated such that the peripheral equipments in lower cost and the whole machine can carry on sexual high. the core slice two a ttl/cmos and let electricity flat lose into, have good
30、anti-jamming, two output terminal can pick flooding dynamic electric machine straight to the shipment of positive reverse move and it has had a big electricity flow flooding dynamic can force, each call way can pass over 800ma continuous current, peak current capacity of 1. 5 0a; 2. at the same time
31、 it has lower output saturation pressure drop and the static electricity, the built-in clamp a diode can release the perceptual load of reverse current impulse, making it the drive relays, dc motors, stepping motor or switch power tube the use of safe and reliable.follow tracing car system to common
32、 at89c51, complementary with relatively simple components and circuit design, the smooth completion of follow under the premise of tracing function, and fully considered appearance, costs, so most of the circuit car by manual welding is complete. in the design, we never in a circuit increase redunda
33、nt functions, but retained various hardware interface and software subroutines interface to facilitate the expansion and development after.2. system hardware design2. 1 motor driver module designin making intelligent car, after left, right wheel respectively with two speed and torque basic identical
34、 dc motor driven deceleration, bolt-on trunk-lid spoiler department to install a direction wheel, then through the i/o mouth to control two dc slowing down motor speed and steering can be achieved on the car to the left, turn right and straight line.motor driver using a integrated electrical machine
35、 flooding dynamic core slice l 298n. l298n is st the product of the company, the internal containing four channel logical drive circuit, it is a kind of two phase four phase motor drive, namely the special contains two h bridge of high voltage large current commander bridge type drive, acceptance cr
36、iteria ttl logic level signals, be driven 46v, 2a below the motor.2. 2 tracing module designtracing module mainly composed by photoelectric sensor reflex. photoconductive resistance of the resistance of the light with the surrounding environment changes, when the ltt white lines above, light emissio
37、n strongly; the ltt black line above, light emission are relatively weak. so when photoconductive resistance in white line and black line above the elements will occur significantly changes, the resistance changes value after comparator can output high level. but this way environmental influences bi
38、g, work is not stable. this article actual use is rpr220 type reflex sensors made tracing module.rpr220 is an integration of reflective photoelectric detector, the transmitter is a gaas infrared light emitting diode and the receiver is a high sensitivity silicon photoelectric triode flat. when the l
39、ight emitting diode reflected back, triode conduction and output low level.2. 3 obstacle avoidance module designobstacle avoidance module mainly composed by infrared reflection sensor. infrared reflection sensor by one infrared tubes (launchers) and 1 photoelectric diode (receiver) constitute, infra
40、red tubes out to meet the infrared object reflective sex strong after be turned back, by photoelectric diode receiving, cause photoelectric diode current increases, light born this change into voltage signal, it could be processor receives and processing.2. 4 remote control module designthis module
41、will launch end uses high sensitive h l - 5000 type universal television remote control, the receiver using receive frequency for 38kh zs receiving head 1838, this module and the single chip computer interface is very convenient. in addition, for the red outside meet after harvest of plait code lett
42、er number, the department tasseled set when shipped with project of at89c52 single chip microcomputer external interruption to receive, signal the falling edge of trigger external interruption. in order to recognize a complete key signal, must for each coding pulse width were measured with discrimin
43、ant receives the pulse is! 0 still! 1 , the microcontroller timer/counter to measuring pulse width. timer/counter except points than can be set, from except 2 to except 2048, measurable pulse width can reach 500m s. this paper set except points for 12, namely than 12 points frequency, because the ex
44、ternal clock is about 12mh z, clock cycle for 1 s, so the timer/counter for 1 per timing once s.2. 5 alarm module designalarm module core chip 110 ic, can choose application in automobile, motorcycle, alarms, personal riot device, door magnetic alarm device and etc.3. system software designthis system software modular structure, the main program, initial anti-fuzzy procedures, interrupt subroutines, delay subroutines, buttons pronunciation subroutines, buttons scanning subroutines constitutes.3. 1 tracing subroutines designtracing module is designed by the left right photoelectric sensor out
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