【正文】 有反射型和透射型二種，本實驗裝置是透射型的，傳感器端部有發(fā)光管和光電池，發(fā)光管發(fā)出的光源通過轉(zhuǎn)盤上的孔透射到光電管上，并轉(zhuǎn)換成電信號，由于轉(zhuǎn)盤上有等間距的6個透射孔，轉(zhuǎn)動時將獲得與轉(zhuǎn)速及透射孔數(shù)有關(guān)的脈沖，將電脈計數(shù)處理即可得到轉(zhuǎn)速值。三、實驗原理霍爾測速的原理利用霍爾效應(yīng)表達(dá)式：UH＝KHIB，霍爾測速的原理如圖11所示。實驗一 測速實驗一、實驗?zāi)康牧私饣魻杺鞲衅?、光電傳感器的測速原理及方法。二、實驗儀器THSRZ1傳感器實驗臺，霍爾傳感器、光電傳感器、+5V、2～24V直流電源、轉(zhuǎn)動源、頻率/轉(zhuǎn)速表、直流穩(wěn)壓電源、數(shù)顯直流電壓表。當(dāng)被測圓盤上裝上N只磁性體時，轉(zhuǎn)盤每轉(zhuǎn)一周磁場變化N次，每轉(zhuǎn)一周霍爾電勢就同頻率相應(yīng)變化，輸出電勢通過放大、整形和計數(shù)電路就可以測出被測旋轉(zhuǎn)物的轉(zhuǎn)速。四、實驗內(nèi)容與步驟霍爾測速內(nèi)容與步驟（1）安裝根據(jù)圖12，將霍爾傳感器安裝于傳感器支架上，且霍爾組件正對著轉(zhuǎn)盤上的磁鋼?！?～24V”直流穩(wěn)壓電源接到“轉(zhuǎn)動源”的“轉(zhuǎn)動電源”輸入端。通過示波器來觀察測霍爾組件輸出的脈沖波形。2~24V電壓輸出接到圖13三源板的“轉(zhuǎn)動電源”輸入，并將2～24V輸出調(diào)節(jié)到最小，+5V電源接到三源板“光電”輸出的電源端，光電輸出接到頻率/轉(zhuǎn)速表的“fin”。在表12記錄下驅(qū)動電壓V4和轉(zhuǎn)速RPM數(shù)據(jù)。表12V4（V）RPM五、實驗報告分析霍爾組件產(chǎn)生脈沖的原理，并根據(jù)記錄的驅(qū)動電壓和轉(zhuǎn)速，作V1RPM曲線。對這2種測速方法進(jìn)行對比。學(xué)會繪制標(biāo)定曲線。二、實驗儀器THSRZ1傳感器實驗臺，應(yīng)變傳感器實驗?zāi)K、托盤、砝碼、數(shù)顯電壓表、177。4V電源。金屬箔式應(yīng)變片就是通過光刻、腐蝕等工藝制成的應(yīng)變敏感組件，如圖21所示，四個金屬箔應(yīng)變片分別貼在彈性體的上下兩側(cè)，彈性體受到壓力發(fā)生形變，應(yīng)變片隨彈性體形變被拉伸，或被壓縮。設(shè)E為電橋電源電壓，則電橋輸出與各橋臂應(yīng)變有如下關(guān)系：圖 21電子稱實驗原理利用全橋測量原理，通過調(diào)節(jié)放大電路對電橋輸出的放大倍數(shù)使電路輸出電壓值為重量的對應(yīng)值，電壓量綱（V）改為重量量綱（g）即成一臺比較原始的電子稱。差動放大器調(diào)零。15V電源，檢查無誤后，合上主控臺電源開關(guān)，將差動放大器的輸入端Ui短接并與地短接，輸出端Uo2接數(shù)顯電壓表（選擇2V檔）。關(guān)閉主控臺電源。圖22加托盤后電橋調(diào)零。將10只砝碼置于傳感器的托盤上，調(diào)節(jié)電位器Rw3（滿量程時的增益），（2V檔測量）。重復(fù)5步驟，直到精確為止，把電壓量綱V改為重量量綱Kg即可以稱重。去除砝碼，托盤上加一個未知的重物（不要超過1Kg），記錄電壓表的讀數(shù)。計算靈敏度L=ΔU/ΔW和非線性誤差δf ，并求出未知的重物的重量。 實驗三 單自由度系統(tǒng)自由衰減振動及 固有頻率和阻尼比的測量一、實驗?zāi)康牧私鈫巫杂啥茸杂伤p振動的有關(guān)概念。學(xué)會根據(jù)自由衰減振動波形確定系統(tǒng)的固有頻率和阻尼比。三、實驗原理單自由度系統(tǒng)的力學(xué)模型如圖31所示。 圖32此波形有如下特點： 1．振動周期大于無阻尼自由振動周期T，即。圖33記錄單自由度自由衰減振動波形。繪出振動波形圖波峰與波谷的兩根包絡(luò)線（參照圖32），然后設(shè)定，并讀出個波經(jīng)歷的時間t，量出相距個周期的兩振幅的雙振幅、之值，計算阻尼比和固有頻率。根據(jù)實驗數(shù)據(jù)按公式計算出固有頻率和阻尼比，計算結(jié)果填入下表。掌握被動隔振的基本方法。二、實驗儀器ZK4VIC振動與控制實驗臺，空氣隔振器，電動式激振器，壓電式加速度傳感器，ZK4JCZ型激振測振儀，虛擬式測試儀器庫。在廠礦，振源通常是振動較大的機(jī)器設(shè)備，振源的振動通過地基傳至周圍環(huán)境和儀器設(shè)備。被動隔振是為了防止周圍環(huán)境的振動通過機(jī)腳、支座傳至需要保護(hù)的精密儀器和設(shè)備，故又稱為防護(hù)隔振，其目的在于隔離或減小振動的傳遞，也就是隔離響應(yīng)，使精密儀器和設(shè)備不受基座運動而引起的振動的影響。設(shè)備的質(zhì)量為m，減振器的剛度為k、阻尼系數(shù)為c。被動隔振的效果可用隔振系數(shù)或隔振效率來衡量。當(dāng)頻率比時，即，隔振器起到了隔振作用。共振時，被隔離體系不可能正常工作。因此，要達(dá)到隔振目的，彈性支承固有頻率的選擇必須滿足。但也不宜過大，因為大意味著隔振裝置要設(shè)計得很柔軟，靜撓度要很大，相應(yīng)地體積要做得很大，并且安裝的穩(wěn)定也差，容易搖晃。故實際中一般采用，相應(yīng)的隔振效率E可達(dá)到（80～90）%以上。將傳感器I、Ⅱ分別置于簡支梁和質(zhì)量塊上，用來測量簡支梁振幅A1和質(zhì)量塊振幅A2。激振信號源輸出正弦信號驅(qū)動電動式激振器，對簡支梁激振。當(dāng)剛出現(xiàn)時，說明剛滿足，這時的激振頻率就是隔振器能起到隔振作用的最低頻率。用共振法測出隔振系統(tǒng)固有頻率 表41激振頻率f1(Hz)頻率比λ=f1/fo振幅A1振幅A2隔振系數(shù)η=A2/A1隔振效率E=(1η)100%根據(jù)表41繪出Eλ隔振特性曲線。 to implement , do not want to, dare not, not with disciplinary ruler to supervision。 not to have conquered, but to have fought well. 2, the plain is the background of life. Live a plain life, give up on themselves is not a coward, but the wise answers。 not unrewarding perfunctorily, but calm attitude of life of unrestrained selfconfidence. Plain living, there is no noise noisy, no earthly troubles, more did not fill in the discontent of desire, some just a calm, a calm. 3, memory of heart will not good things to erase the, life is a When no movie, pain is a beginning, the struggle is a kind of process, death is a kind of ending. Give up this giving up is the helpless, do not give up the abandoned, do not give up this giving up is ignorance, do not give up should not give up is persistent. 4, a thing figured is heaven, think impassability is hell. Since the living, to live better. Sometimes we because of too narrowminded, too care around the chores and penny wise and pound foolish, not worth the candle. Some things to attract trouble and worry, pletely depends on how we look at and deal with it. Don39。t get into a blind alley, don39。t be narrowminded. Poke to care, is a kind of openminded, a free and easy. 5, I am not afraid of others behind me a knife, I afraid to look back and see stab me, is my intention to treat people。m afraid he turned to it as a joke to tell don39。 and when we are in a negative state of mind, you will find many depressed things。 loss of sink, Eritrea pany. When you are in adversity, may wish to change a point of view to think everything over to the good Think, because good mentality decided the fate of the! 7, people are tired, rest。 you pain, no one can understand. Then you only tears to smile. 8, each people have youth,Each youth are a story, the life of the world never gets easier, I want what, wish the world all know, as has been the same。s mouth, because words will reduce its importance。t envy who. Like a person is a kind of feeling, not like a person is true. The truth is easy to explain, I feel Is unspeakable. The best travel life is that you in a strange place found a long lost touched. 11, happy life not in the bustling in, and in the peace of mind。am, like a movie, learn to appreciate, learn to be grateful, learn tolerance, and goodness, helping others. Instead of accusing the society, as into one。t envy him A sum of, don39。t let everyone like you, so also do not want to do. Life is too short to go crazy to love to go to waste, to chase the dream to regret. 15, when temper, a blessing to go. A wounding elegant people, the key is to control their own emotions. With the mouth is the most stupid behavior. A control negative emotions than a can take a city more powerful water flow slow, language is expensive. People spent two years of time to learn to speak, but to spend a few years time to shut up. That is a kind of ability, that is a kind of wisdom. 16, life is not perfect, sometimes, growth is not a cry, not an eyeful of tears, there is no trace of emotion, there is no gleam of hope, no desire, no action, no static, there is only one kind of downward sinking feeling, sink A murky? 6? 7? 6? 7 sink? 6? 7? 6? 7 toward the bottom of the sink. 17, in some way, do not go, you will not know the other side scenery is beautiful. To you is not good, you do not mind too much, no one has an obligation to you。 how do you treat people, does not represent how others treat you, if cannot see through this point, only inviting worry. 18, time is like a sponge in the water, as long as you are willing to squeeze, the total wate