【正文】
utoff state ,double LM324 operational amplifier output low level to microcontroller ,by program processing ,If left not detected light ,then left correct direction。這種方案能實(shí)現(xiàn)對(duì)電動(dòng)車(chē)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,可慢豬對(duì)系統(tǒng)的各項(xiàng)要求。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。該芯片有兩個(gè)TTL/CMOS兼容電平的出入,具有良好的抗干擾性;兩個(gè)輸出端能之間驅(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(guò)800mA的持續(xù)電流,~;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(kāi)關(guān)功率管的使用上安全可靠。但是這種方式受環(huán)境影響大,工作不穩(wěn)定。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,以判別接收到的脈沖是0還是1,利用單片機(jī)中的定時(shí)器/計(jì)數(shù)器來(lái)測(cè)量脈沖寬度。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(chē)。三 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。避障模塊主要有紅外反射式傳感器組成。電機(jī)驅(qū)動(dòng)采用片集成電機(jī)驅(qū)動(dòng)芯片L298N。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。同樣由于開(kāi)關(guān)頻率高,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)。本設(shè)計(jì)采用AT98C51單片機(jī)作為智能小車(chē)核心控制器。 If the right has not been detected light ,then turn correct direction . motor control and driving module design Because use is double drive cars ,this part of the circuit must be able to output of two different voltage values ,respectively to 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 channels pushpull power amplifier applicationspecific 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 antijamming ,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 ~OA 。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(chēng)PWM變換器。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)。循跡小車(chē)系統(tǒng)以常見(jiàn)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,又充分考慮到了成本、外觀等問(wèn)題,因此小車(chē)的大部分電路有手工焊接完成。本文實(shí)際采用的是RPR220型反射式傳感器制作的循跡模塊。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)500ms。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。報(bào)警模塊的核心芯片選擇110報(bào)警IC,可應(yīng)用于汽車(chē)、摩托車(chē)、防盜器、個(gè)人防暴器、門(mén)磁報(bào)警器等場(chǎng)所。當(dāng)發(fā)光二極管發(fā)出的光反射回來(lái)時(shí),三級(jí)管道通病輸出低電平。二 系統(tǒng)硬件設(shè)計(jì)在制作智能小車(chē)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(chē)頭前部裝一個(gè)方向輪,然后通過(guò)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(chē)的轉(zhuǎn)輪、右輪和直行。當(dāng)兩個(gè)傳感器同時(shí)接收到光時(shí),直線前進(jìn)。由于電流波形比VM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。 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 parator can output high level. But this way environmental influences big, work is not stable. This article actual use is RPP220 type reflex sensors made tracing module.RPR220 is an integration of reflective photoelectric detect