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==========================================喜歡這套資料就充值下載吧。。。資源目錄里展示的都可在線預(yù)覽哦。。。下載后都有,,請放心下載,,文件全都包含在內(nèi),,【有疑問咨詢QQ:414951605 或 1304139763】
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機動車輪椅固定及其使用者的約束系統(tǒng)
前言——為了那些使用機動車旅行卻沒有能力從輪椅中移動出來的人,輪椅必須像汽車座椅一樣來使用。這就通常意味著由車輛制造商提供的成員約束系統(tǒng)在某些緊急狀況下不能夠提供足夠的保護。另外,輪椅必須被固定在車上以便不會強加載荷給它的使用者,并且在碰撞或突然的車輛回旋情況下不會對其他車上人員造成傷害。因此,要為輪椅及其使用者提供約束性的保護,使用一些零部件以及相關(guān)的設(shè)備來固定輪椅并對其使用者進行約束。
這篇設(shè)計和機動車性能表現(xiàn)方面的文章論述的就是輪椅的固定及其使用者的約束系統(tǒng),簡稱為WTODS。它的目的就是為了鼓勵設(shè)計,測試和實施。使用WTODS系統(tǒng)在正面碰撞時可以有效的保證輪椅的安全和約束使用者,并且在某些特定情況下的表現(xiàn)是可以與制造商提供的乘坐安全性和輪椅使用者的約束相比較的。我們關(guān)心的主要是機動車在發(fā)生正面碰撞的情況下輪椅使用者所能受到的潛在傷害,也希望在成功保護輪椅使用者的同時,在正常的旅行期間可以增加駕駛員及其他成員的安全性和舒適性。這篇文章不應(yīng)該被用來鼓勵那些沒有能力駕駛或者限制對輪椅進行運輸?shù)那闆r。
因為WTODS的制造商們不能控制和指定他們產(chǎn)品的最終用途,所以48KM/H,20G的沖擊測試被指定在附錄A中,用來限制WTODS系統(tǒng)在總重量小于7000KG的整車上的使用。在更大的車輛中,也可以使用WTODS系統(tǒng)來保證運輸?shù)陌踩?,但是不會依照這篇文章所提到的使用標準。
和任何一個座椅相比,輪椅是成員安全系統(tǒng)的一個重要組成部分,并會在正常旅行期間為使用者提供穩(wěn)定性和舒適性。輪椅的設(shè)計和表現(xiàn)在機動車的乘坐中是被單獨談?wù)摰模鄳?yīng)的ANSI/RESNA標準正在發(fā)展中。
設(shè)計要求:
1.完成WTORS--WTORS應(yīng):
a. 以一個輪椅和一個乘員為使用對象;
b. 不要求用來固定輪椅和實施成員約束的零件穿過輪椅的輪子;
c. 在不使用工具的情況在在60秒內(nèi)可以對輪椅及其使用者進行脫離;
d. 不需要拆除輪椅的材料,鉆探輪椅架,變形輪椅,焊接,或者使用粘合劑,安裝期間,除非是為WTORS系統(tǒng)使用的特殊輪椅或輪椅制造商允許的造型變革;
e. 一旦安裝,可不使用工具操作;
f. 硬件設(shè)備,只包括永久連接的WTORS或WTORS組件;
g. 設(shè)計要防止無意中將所有螺紋緊固件松動;
h. 包括一個人工代用裝置,在電源故障的情況下解除固定和約束;
i. 包括錨地緊固件,硬件和符合規(guī)格的類似硬件,下面是基于材料,大小和緊固件的使用量模擬試驗附錄A;
2.輪椅的固定及固定的組件應(yīng):
a. 不需要依靠輪椅進行制動;
b. 輪椅的安全性能實現(xiàn)是依靠固定件的設(shè)計,而不是依靠成員約束來實現(xiàn);
c. 提供一個不使用工具來消除輪椅自由移動的方法;
d. 如果WTORS系統(tǒng)采用了四點皮帶固定方式,那么每條皮帶都可以不使用工具來進行長度調(diào)節(jié),這類的調(diào)整幅度,前帶后帶所能達到的最高值和最低值包含在表格1中,包括一個至少有25MM的皮帶延長調(diào)整機構(gòu);
表格1-—四點皮帶固定方式的擴展調(diào)整幅度:
皮帶交匯點 最小長度(MM) 最大長度(MM)
后排 485(19) 740(29)
前排 410(16) 710(28)
〈長度定義為從輪椅安全點相對應(yīng)的固定交點到沿著皮帶的長度方向與輪椅接地平面線的交點的直線距離〉
e. 計算說明安全點與其他四個固定點在幾何學(xué)上的關(guān)系,在附錄E4中說明了在結(jié)構(gòu)上安全點與其他組成部分的關(guān)系;
f. 包含一個通過視覺或聽覺來引起注意的設(shè)備,在相接處準確銜接后會予以顯示;
3.成員約束—-WTORS也可以被設(shè)計成通過乘客或駕駛員進行約束,包含的成員約束應(yīng)滿足以下要求:
3.1 WTORS的成員約束應(yīng)包含兩個部分--骨盆和軀干的約束;
3.2 成員約束可以被設(shè)計成直接與車輛相固定,和輪椅的組成部件相固定,或者直接通過部件來和輪椅相連接。成員約束系統(tǒng)不能被設(shè)計成依靠輪椅傳播載荷的約束結(jié)構(gòu),除非是專為WTORS設(shè)計的特定輪椅,當(dāng)和輪椅組合以后WTORS應(yīng)滿足6.2 的要求。通過附錄1可以看到WTORS 的測試結(jié)果;
3.3上部軀干和骨盆的約束長度可以不通過使用工具來進行調(diào)節(jié);
3.4 當(dāng)WTORS以附錄B的標準在建立過程中,如果適合的話,骨盆的約束,其固定點和過渡點的設(shè)計應(yīng):
a. 實現(xiàn)如圖4b所要求的側(cè)面觀察視野范圍;
b. 實現(xiàn)如圖4a所要求的后面視野范圍及區(qū)域內(nèi)的固定;
c. 提供足夠的皮帶長度來對骨盆進行調(diào)節(jié),測量固定點到固定點的距離,通過可以增加或減少的200MM長度及至少25MM的自由長度調(diào)節(jié)來實現(xiàn)全時的約束;
3.5當(dāng)WTORS以附錄B的標準在建立過程中,對軀干應(yīng)提供足夠的約束長度,較長的調(diào)整增量為200毫米,并且可以縮短到300毫米,有至少25毫米的自由延伸長度可以全時對成員進行約束;
4(a) 4(b)
附錄四
注意—注意骨盆約束的突出角和輪椅參考側(cè)平面之間的角度,以及成員背部與輪椅參考背平面之間的角度;
3.6 對于WTORS系統(tǒng),應(yīng)該通過軀干固定點和軀干過渡點的計算來實現(xiàn)肩部和胳膊的約束并對其進行支持,這些位置定位點和支持結(jié)構(gòu)應(yīng):
a. 使用者乘坐的高度和肩部的水平線以上應(yīng)該有足夠的可調(diào)節(jié)長度;
b. 1100毫米以上,至少應(yīng)設(shè)輪椅機,以接近地面以上的肩膀部分,來實現(xiàn)在輪椅的乘坐中肩部以上部分的約束;
注意1—如果上面的過渡點確定的話,那么固定點應(yīng)在下面1100MM,反之就在上面1100MM;
注意 2—雖然FMVSS 210 允許軀干的固定點應(yīng)被固定在成員肩部水平以下一個明顯的距離上,這樣的位置考慮被認為是不合理的,不符合這篇文章,可能導(dǎo)致向下方向的載荷對脊柱造成傷害。
3.7 從安裝時所指定的附錄B中的輔助中心線來看,與骨盆交界的肩膀三點約束應(yīng)不低于150MM;
3.8 依照這篇文章的要求,在主要依靠輪椅固定和皮帶固定來實現(xiàn)約束的情況下,氣帶只產(chǎn)生輔助的約束性能;
3.9 WTORS的實現(xiàn)不應(yīng)該依靠氣袋來遵守這篇文章;
4. 試驗報告---WTORS的制造商應(yīng)具有文件和檔案資料,其中包括:
4.1 依據(jù)4.2和4.3的設(shè)計要求和相關(guān)的報表,WTORS系統(tǒng)應(yīng)符合設(shè)計要求,包括:
a. 依據(jù)表格1的要求,表明四點式安全皮帶的最大和最小固定長度;
b. 最終裝配的幾何學(xué)固定四點要符合附錄E4的幾何學(xué)要求;
c. 骨盆約束的確定要符合附錄B;
d. 建立和測量骨盆約束的長度調(diào)整要符合附錄B的要求;
e. 建立和測量軀干約束的長度調(diào)整要符合附錄B的要求;
f. 依據(jù)WTORS提供的軀干固定點和其他相關(guān)的點,長度以及長度的調(diào)整要符合4.3.6的要求;
g. 建立和測量依據(jù)輔助中心線制定的骨盆和肩部約束距離要符合附錄B的要求;
4.2 遵守國家相關(guān)規(guī)定:
a. 表格2中的FMVSS 209;
b. WTORS系統(tǒng)中帶狀材料的可燃性要求要滿足FMVSS 302;
4.3 遵守國家相關(guān)正面碰撞試驗附錄A,包括:
a. 描述測試設(shè)備,包括使用模擬式?jīng)_擊試驗,儀器與信號處理技術(shù),幀速度為制作每部影片或錄像的速度,測試減速度等方法用以衡量和檢驗輔助中心線和測試輪椅,并增加測量的精度;
b. 關(guān)于減速度的跳動計算說明是否滿足A.4.3和附錄A1,這其中包括跳動的持續(xù)時間,減速度在毫秒數(shù)量上的累積時間超出15g到20g;
c. V形安全帶的測量與計算;
d. WTORS系統(tǒng)的全面鑒定,錨地緊固件,試驗輪椅,輔助中心線;
e. 所有WTORS的試驗輪椅的相關(guān)P點都要滿足文章的要求;
f. 所有固定皮帶和骨盆相對應(yīng)的橫縱向約束確定以后,與之相關(guān)的側(cè)面視野,正面視野,背面視野可以酌情處理;
g. 試驗建立起來后,應(yīng)該對那些非WTORS制造商提供的零部件有一個具體的描述;
f. 試驗輪椅是否停留在試驗平臺上;
h. 如果測量的話,相比于初步測試定位,試驗輪椅的參考測試平面將會改變;
k. 任何WTORS系統(tǒng)承載部分的鑒定,如果顯示部分有撕裂,破碎,斷裂,或徹底失敗等現(xiàn)象的發(fā)生,是設(shè)計上的漏洞或者制造上的問題;
l. 在6.2.d中指明了短途旅行的水平線最高點,是否有任何短途旅行超過了限制會在這篇文章的表格3中表明;
m. 一份說明書,關(guān)于是否在不使用工具的情況下將成員和試驗輪椅釋放出來;
n. 一份說明書,依據(jù)6.2.e的計算結(jié)果表明試驗輪椅是否對其成員施加載荷;
4.4 依據(jù)在附錄3中的部分試驗數(shù)據(jù),WTORS系統(tǒng)的測試和規(guī)格應(yīng)該包括:
a . WTORS系統(tǒng)的全面鑒定,錨地組件的測試,安全性;
b. 全面的描述,包括必要的照片,每部分的測試結(jié)果;
c. 分離阻力的步驟描述;
d. 每個測試的結(jié)果,換句話說,安全組件或固定組件是否分離或仍然接合;
4.5 依據(jù)附錄D指明的皮帶延誤調(diào)整器和任何有關(guān)的其他方面規(guī)定,包括:
a. WTORS系統(tǒng)的全面鑒定,皮帶類,每一個調(diào)整裝置的測試;
b. 測試儀器和程序的描述;
c. 每次調(diào)整器測試的皮帶延誤量;
d. 一項聲明,說明25MM的極限是否超過每次調(diào)整器測試;
e. 一項聲明,說明是否在WTORS系統(tǒng)中所有的輪椅固定調(diào)整器都會通過測試。
5. 定義與概念--為了更好的理解這篇文章,提供下面的概念說明:
5.1 錨——硬件和裝置的組合件,用來傳遞從一直由輪椅固定到車輛或從一個約束力到輪椅固定或車座底板的力;
5.2 錨鉸接點——一個在車輛,輪椅或輪椅固定件或車座底板上的力,錨便鉸接于此;
5.3 ANSI——美國國家標準協(xié)會振動等級;
5.4 人機工程學(xué)測試設(shè)備(ATD)——一個模擬的人體模型,用來模擬機動車在碰撞環(huán)境下的情形;
5.5 自動鎖緊裝置——一個裝置通過一套主動自鎖機構(gòu),當(dāng)機構(gòu)鎖緊時用之來承受約束力來實現(xiàn)調(diào)節(jié);
5.6 后約束——一套裝置或系統(tǒng)實現(xiàn)限制車廂的后傾運動從而提供背后的支持力;
5.7 皮帶——一條用網(wǎng)格材料做成的吸能帶子,用來做成員的約束;
5.8 對接式固定——一套輪椅安全裝置,其設(shè)置被初始化為輪椅傾向一個恰當(dāng)?shù)奈恢茫?
5.9 應(yīng)急鎖緊執(zhí)行器——將通過調(diào)整硬件鎖定機制,激活了汽車的加速度,皮帶相對于汽車運動,在緊急時刻可以進行自動鎖緊;
5.10 邊緣裝置——錨地硬件和成員約束的直接固定部分,用來固定成員約束帶,直接連接在主錨點和輪椅上的安全點;
5.11 緊固件——器材保障,用機械設(shè)備,零部件和其他零件實現(xiàn),
(這些不包括:螺絲,螺母,螺絲釘,鉚釘,夾具等)
5.12 前方視野——輪椅坐在最前排的成員臉部與汽車之間的參考平面;
5.13 四點固定——輪椅固定系統(tǒng),以四個不同的點系在輪椅框架上,輪椅固定在汽車上的四個獨立支柱點,文中所給的是典型的四點固定系統(tǒng),采用四個固定皮帶,兩個屬于前輪,兩個屬于后輪;
5.14 底部約束——一個至少由一名成員的皮帶用來提供成員的骨盆約束和兩個肩膀以及軀干部分的約束;
5.15 頭部約束——用來限制成員頭部的移動;
5.16 沖擊模擬器——加速裝置,加速與減速的組合,汽車部分或模擬汽車結(jié)構(gòu),包括測量儀器的相關(guān)資料;
5.17 沖擊滑板——在模擬器上的部分,對其產(chǎn)生影響,可以展開進行沖擊測試;
5.18 獨立成員約束——直接進行的約束或與鉚接的車輛部分分開,進行輪椅的固定;
5.19 綜合成員約束——成員約束中的骨盆約束,兩個肩膀的約束,軀干的約束,要固定在輪椅上;
5.20 成員約束錨地——硬件組裝和配件其中將載荷直接由汽車,輪椅和輪椅約束系統(tǒng)分擔(dān);
5.21 成員約束——成員約束系統(tǒng)或裝置,用來防止或減少車輛接觸,防止在車輛中發(fā)生危險情況;
5.22 OEM——設(shè)備制造商;
5.23 骨盆克制——在極限運動范圍內(nèi)限制骨盆的運動,降低軀干克制;
5.24 點——參考點,從地面接地處距離為100MM的位置,縱向的輪椅約束位置,曲面與坐椅和靠背的面想接點;
5.25 姿勢支持——用于支持一個人在預(yù)期位置的零部件,但不會通常用于在車輛碰撞時對成員產(chǎn)生約束;
5.26 安全硬件——輪椅固定系統(tǒng)的后端設(shè)備,連接在輪椅上;
5.27 安全點——位于輪椅上的點,連接在輪椅接觸點的末端單元;
5.28 托盤——一個網(wǎng)狀材料帶,用于輪椅的固定;
5.29輪椅分析——用儀器來模擬輪椅的固定情況;
5.30 SWC——輪椅分析的縮寫;
5.31 實驗輪椅——試坐輪椅的樣品,用來代替實際的輪椅來進行實驗;
5.32 輪椅固定錨地——硬件組裝和配件,載荷直接分配在輪椅上;
5.33 WTORS——輪椅固定約束系統(tǒng)的縮寫。
參考文獻
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長安大學(xué)畢業(yè)設(shè)計(論文)開題報告表
課題名稱
兼容殘疾輪椅的中型客車造型設(shè)計
課題來源
自選項目
課題類型
工程設(shè)計
指導(dǎo)教師
郭應(yīng)時 教授
學(xué)生姓名
王琦瑋
學(xué) 號
2201030108
專 業(yè)
車 輛 工 程
課題的意義
隨著我國國民經(jīng)濟的飛速發(fā)展,全國各地高速公路、汽車專用線、汽車快速道如雨后春筍般建成通車高速公路的迅猛發(fā)展和旅游業(yè)的繁榮,使得以城市間客車運輸和旅游運輸為主要對象的客車迅猛發(fā)展。截至2005年底,全國等級公路里程159.18萬公里,占公路總里程的82.5%。其中二級及二級以上高等級公路里程32.58萬公里,占公路總里程的16.9%。按公路技術(shù)等級分組,各等級公路里程分別為:高速公路41005公里、一級公路38381公里、二級公路246442公里。公路條件的改善以及城鄉(xiāng)人民生活水平的提高,促進了我國汽車工業(yè)的發(fā)展。做為汽車家族重要組成部分的中型客車,近年來同樣進入了前所未有的發(fā)展時期。發(fā)展帶來機遇的同時也帶來了挑戰(zhàn),盡管經(jīng)過國家政策的調(diào)控,我國的客車整車生產(chǎn)企業(yè)在總量上有所減少,但企業(yè)個體競爭力明顯增加,產(chǎn)生了諸如宇通,蘇州金龍(金龍聯(lián)合汽車工業(yè)(蘇州)有限公司),大金龍(廈門金龍聯(lián)合汽車工業(yè)有限公司),小金龍(廈門金龍旅行車有限公司),安徽安凱等一批極具競爭力的企業(yè),這就使得各生產(chǎn)企業(yè)要不斷加快推出新產(chǎn)品的速度和提升產(chǎn)品質(zhì)量,而作為產(chǎn)品更新?lián)Q代的重要方面之一的客車外形的變化更是明顯地加快。
現(xiàn)就國內(nèi)外大型客車造型的風(fēng)格、特點及其歷史、現(xiàn)狀、發(fā)展趨勢等作簡要分析:
一,客車造型的整體風(fēng)格與特點
1.整體風(fēng)格 客車造型最初是從貨車演變而來。早期客車采用貨車的發(fā)動機和底盤改裝而成,從20世紀40年代起,客車的設(shè)計逐漸脫離貨車的范疇而走上獨立設(shè)計的道路,開始生產(chǎn)專用非承載式車架,進一步發(fā)展為半承載式,并形成特殊的設(shè)計風(fēng)格。
歐洲的Setra、MAN、BENZ、NEOPLAN、VOLVO、SCANIA、、IVECO、BOVA和日本的HINO、ISUZU等都是世界著名的客車生產(chǎn)企業(yè),其中有些作為專業(yè)的客車公司,其對行業(yè)的發(fā)展起到了很大的推動作用。
現(xiàn)代客車絕大多數(shù)采用直角六面體的平頭式造型,基本的風(fēng)格有兩種:一是直線條方基調(diào)的意大利型;另一是大曲面流線形的德國型。前者線條挺拔、洗練,能增加車廂的空間、擴大通透感,視野開闊,給人剛建的感覺;后者突出空氣動力學(xué)特性,給人飽滿、圓潤、耐看的感覺。
我國自80 年代以來, 各企業(yè)紛紛推出了方基調(diào)、小圓角、大弧面、流線感較強的車型。因為小圓角和大弧面相結(jié)合, 具有柔和、圓潤、飽滿的特征, 能使客車產(chǎn)生剛?cè)峤Y(jié)合、剛中有柔的效果, 增加其藝術(shù)感染力。
2客車造型的特點 客車以前、后圍為重點, 尤其前圍更為重要。我們可以把前圍比著人的臉, 那么車燈、進氣格柵、標徽等就成了五官, 整車的神態(tài)盡顯于其上。前圍采用超大雙曲面的全景擋風(fēng)玻璃, 加上較小的A 柱結(jié)構(gòu), 最大限度地改善了乘員的視野。客車的側(cè)圍與頂部的設(shè)計與之相呼應(yīng), 加上一些裝飾件的運用, 與之形成統(tǒng)一的整體?,F(xiàn)代客車一般都配置了空調(diào), 側(cè)窗采用全封閉粘接玻璃, 有時也在尾部和司機玻璃上再開小的活動窗。而進、排氣口的確定則要依賴于空氣動力學(xué)實驗或相關(guān)經(jīng)驗。
二,客車造型的歷史、現(xiàn)狀及發(fā)展趨勢
1.國內(nèi)大型客車造型的歷史、現(xiàn)狀及發(fā)展趨勢
1.1歷史回顧 我國大中型客車的發(fā)展,始于20世紀60年代,由交通部組織開發(fā)的JT663型客車(見圖1),車身表面為大曲率圓基調(diào)。該車代表了當(dāng)時國內(nèi)客車產(chǎn)品的最高水平, 20世紀60~70年代我國大型客車外形基本上以JT663這種大曲率圓基調(diào)的車身外形為主,JT663的生產(chǎn)一直維持到20世紀80年。
圖1 JT663型客車
20世紀80年代末,交通部又組織行業(yè)的有關(guān)專家及骨干企業(yè)先后開發(fā)了JT1118及JT6120兩款大型后置發(fā)動機客車,其中JT6120大型客車對20世紀80年代末以及90年代初我國客車的造型設(shè)計影響較大。JT6120大型客車是我國首次開發(fā)的后置全承載式車身的客車,它的外形風(fēng)格與JT663迥然不同,側(cè)圍從裙部到側(cè)窗上緣為樣條曲線,整車的頂蓋與側(cè)圍及前后圍與側(cè)圍的過度采用了小圓角(R40)過渡。該車的前風(fēng)擋造型設(shè)計一改以往的大曲率,而采用邊界小曲率表面略帶球形的外形設(shè)計,比較新穎。因此JT6120一誕生便給人們以耳目一新的感覺,可謂引領(lǐng)時代潮流。JT6120由于當(dāng)時底盤總成不過關(guān),沒有形成批量生產(chǎn),但該車新穎美觀的外形對我國20世紀80年代末、90年代初國內(nèi)客車的外形設(shè)計產(chǎn)生了很大的影響,不少廠家采用該車外形經(jīng)過適當(dāng)?shù)淖兓?,先后開發(fā)了多種暢銷產(chǎn)品。
1.2國內(nèi)長途旅、游客車造型的現(xiàn)狀 隨著我國高等級公路通車里程的不斷增加以及旅游業(yè)的發(fā)展,長途、旅游客車的需求量逐年遞增。國內(nèi)客車企業(yè)通過合資合作或者引進技術(shù),提升了自己的產(chǎn)品開發(fā)水平,而且產(chǎn)品外形變化速度加快,部分產(chǎn)品的外形設(shè)計水平已經(jīng)達到或者接近國外同類產(chǎn)品的水平。圖2為我國目前較有代表性的客車造型,蘇州金龍的KLQ6129Q型客車。
圖2 蘇州金龍KLQ6129Q型客車
目前長途、旅游客車外形造型的主要特點是:
※采用了電動兔耳式倒車鏡,使整車顯得華貴;
※ 側(cè)窗有加大的趨勢,目前側(cè)窗設(shè)計高度達到或接近1 200 mm,約為整個側(cè)圍高度的2/5;
※ 前后保險的"保險"作用逐漸弱化,其外形和整個前后圍縱向特性線成為連續(xù)光滑曲線,使整車造型更加和諧 ;
※ 側(cè)窗造型一改過去的直立柱,多采用曲線立柱,使整車富于變化;
※ 外形各異的燈具對整車外形"畫龍點睛"的作用;
※ 重視細部造型,如輪罩,一改過去呆板的圓形形狀,輪罩的設(shè)計更注重和整車的協(xié)調(diào)統(tǒng)一,同時也更富于變化;
※ 一些新的外飾件的采用,對整車的造型也起到了不同程度的作用。如側(cè)倉門采用鋁合金合頁或橡膠合頁,豪華客車多采用粘接式前后風(fēng)擋玻璃及側(cè)窗,也有的采用推拉式側(cè)窗;
※ 其它外飾件的采用,如側(cè)標志燈、側(cè)反射器、高位制動燈、示廓燈的布置以及車門的型式和布置都對整車的外形有不同程度的作用和影響。
1.3國內(nèi)長途旅、游客車造型的發(fā)展趨勢
※ 隨著全承載式大行李倉車身結(jié)構(gòu)的不斷推廣采用,長途旅游車高度也有增加的趨勢,逐步3.7 m高左右;
※ 整車造型更富于變化,注重流線型,以減少空氣阻力,降低油耗;
※ 隨著公路條件的改善以及整車高度的增加,長途、旅游客車的前后風(fēng)擋玻璃及側(cè)窗將繼續(xù)變大,側(cè)窗將達到或者接近整車側(cè)圍高度的一半,前風(fēng)擋玻璃高度則可能達到1.55m左右;
※ 隨著玻璃鋼等非金屬材料在客車車身上的應(yīng)用范圍的增大,解決了過去金屬薄板沖壓成型的困難,使得整車的前后圍細部造型更加富于變化。
2.國外大型客車造型的發(fā)展趨勢 圖3為歐洲比較典型三軸車造型。
圖3 Setra 416GT-HD型客車
※ 前后圍及整車的造型更加注重流線型,外形更加活潑;
※ 采用各種形狀的組合燈具,富于變化;
※ 車身高度增加,整車造型以小圓角過渡為主,各主要表面如前后圍等局部造型更富有于變化;
※ 前后保險杠逐步消失,不再起"保險"作用;
※ 粘接側(cè)窗的采用使整車外表更加平整。
三,內(nèi)飾的設(shè)計
客車內(nèi)部裝飾的豪華化已成為競爭的主要手段之一。在裝配空調(diào)的基礎(chǔ)上,采用全封閉式側(cè)窗成為80年代客車的標準式樣,先進的空調(diào)系統(tǒng)由電腦控制溫度,使車內(nèi)環(huán)境得到徹底改善,依靠空氣動力性試驗確定排氣及進氣口。
采用粗呢作車內(nèi)裝飾貼面,地板上鋪設(shè)地毯都有助于降低噪聲,同時軟化內(nèi)飾也有助于在發(fā)生事故時對成員的保護。對導(dǎo)線及導(dǎo)管的出入孔、車門、踏板處等嚴加密封,防止車外噪聲的傳入,在頂蓋及側(cè)壁的內(nèi)外蒙皮之間充填硬質(zhì)聚苯泡沫塑料,以消除和降低車身構(gòu)件之間的撞擊噪聲。
綜上所述,客車的外形造型和許多因素有關(guān)系。目前,不論是長途旅游車還是城市公交車的造形設(shè)計都越來越注重細部的處理對整個外形的影響,如何能夠?qū)υ煨偷募毑刻幚碜龅皆跐M足功能需要的前提下,既不畫蛇添足又能和整車造型相協(xié)調(diào)呼應(yīng),仍是體現(xiàn)造型水平的關(guān)鍵所在。我們常常會發(fā)現(xiàn)為什么兩種或幾種外形造型雖然截然不同,但是都給人們以美的感覺,就是因為他們各自的造型協(xié)調(diào)一致的原因
因此,在本設(shè)計中,將采用國際流行的方基調(diào),圓角造型;前圍利用大型雙曲面前擋風(fēng)玻璃,以表現(xiàn)整車的犀利感,輔助表達簡約風(fēng)格;后圍采用平面后風(fēng)窗玻璃,以節(jié)約材料,降低工藝成本,同時與車身側(cè)圍的平面結(jié)構(gòu)相呼應(yīng);平面間采用小圓角過渡,在剛烈中隱約表達出陰柔之美;后視鏡仍采用較為常規(guī)的兔耳式電動后視鏡,以節(jié)約車主的后期維修保養(yǎng)成本。
四,畢業(yè)設(shè)計階段設(shè)計任務(wù)將會分以下階段完成:
(1)分析國內(nèi)外同類車型的造型現(xiàn)狀及發(fā)展趨勢;
(2)畫出設(shè)計草圖,對設(shè)計方案進行分析,選擇出最優(yōu)設(shè)計方案;
(3)與總布置人員一起確定車身造型曲線;
(4)造型附件的確定與選擇,外部及室內(nèi)造型,儀表臺及保險杠造型設(shè)計;
(5)繪制彩色效果圖;
(6)編寫設(shè)計說明書。
指導(dǎo)教師意見及建議:
指導(dǎo)教師簽名:
年 月 日
注:1、課題來源分為:國家重點、省部級重點、學(xué)校科研、校外協(xié)作、實驗室建設(shè)和自選項目;課題類型分為:工程設(shè)計、專題研究、文獻綜述、綜合實驗。
2、此表由學(xué)生填寫,交指導(dǎo)教師簽署意見后方可開題。
畢業(yè)設(shè)計(論文)報告紙 共 2 頁 第 1 頁 裝 訂 線 目錄 第一章 緒論1 1.1 造型設(shè)計的重要性1 1.2 國外客車造型的現(xiàn)狀與發(fā)展趨勢2 1.2.1 具有東方風(fēng)格的日本式3 1.2.2 歐式豪華大客車的幾種典型風(fēng)格3 1.2.3 美洲大客車4 1.3 國內(nèi)客車造型設(shè)計的現(xiàn)狀及發(fā)展趨勢4 1.3.1 長途,旅游客車4 1.3.2 城市客車 5 1.3.3 高檔豪華客車6 第二章 造型設(shè)計的特點,基本原則及要求7 2.1 造型設(shè)計的特點7 2.2 造型設(shè)計的原則7 2.3 造型設(shè)計的要求和方法9 2.3.1 外型9 2.3.2 車內(nèi)布局9 第三章 客車造型的特點以及形式的確定11 3.1 客車造型的特點11 3.1.1 中型客車,適用于城市之間的中短途運輸11 3.1.2 發(fā)動機前置11 3.1.3 前懸短,乘客門中置11 3.1.4 兼容殘疾人座椅11 3.2 整車造型設(shè)計方案以及 CAD 三維實體模型的建立12 3.2.1 造型設(shè)計的重點部分12 3.2.2 本車造型特點14 畢業(yè)設(shè)計(論文)報告紙 共 2 頁 第 2 頁 裝 訂 線 3.2.3 造型的表達以及CAD模型的建立15 第四章 內(nèi)飾,保險杠及附件的設(shè) 計20 4.1 內(nèi)飾20 4.2 保險杠20 4.2.1 單 一 式 保 險 杠 20 4.2.2 整 體 組 合 式 保 險 杠 20 4.2.3復(fù) 合 式 保 險 杠 21 4.3 附件21 4.4 安全裝置22 第五章 材料選用與工藝特點23 5.1 材料選用23 5.2 工藝特點23 第六章 存在的不足及改進的途徑24 6.1 本車的造型設(shè)計存在的不足24 6.2 改進的途徑24 設(shè)計評價分析25 致謝26 參考文獻27 畢業(yè)設(shè)計(論文)報告紙 共 2 頁 第 3 頁 裝 訂 線 畢業(yè)設(shè)計(論文)報告紙 共 2 頁 第 1 頁 裝 訂 線 摘 要 汽車造型相當(dāng)重要,它不但直接影響整車的視覺效果,同時也在很大程度上影 響到產(chǎn)品的市場表現(xiàn)。研究不同檔次客車的造型風(fēng)格和時代流行趨勢,尋找其內(nèi)在 關(guān)系,對于企業(yè)新產(chǎn)品開發(fā)具有重要的指導(dǎo)意義。 文章簡要介紹我國客車造型的發(fā)展和現(xiàn)狀,較詳細的說明了客車整體、局部造 型及內(nèi)飾技術(shù)和在造型中應(yīng)注意的一些問題。介紹了客車造型設(shè)計的含義和評價標 準。簡述了構(gòu)思草圖、效果圖、模型在客車造型設(shè)計過程中的作用。 在本車的造型設(shè)計過程中,結(jié)合兼容殘疾人座椅的造型特點,在客車外觀,內(nèi) 飾設(shè)計和一些細節(jié)問題上都有所創(chuàng)新,并通過 CAD 軟件在三維設(shè)計過程中表現(xiàn)出來。 通過對客車造型特點的研究,把握市場對客車造型的需求,提高產(chǎn)品的市場競爭力。 關(guān)鍵詞:客車,造型,設(shè)計,CAD,殘疾人 畢業(yè)設(shè)計(論文)報告紙 共 2 頁 第 2 頁 裝 訂 線 ABSTRACT Automobile styling is important, it will not only directly affect the vehicles visual effects, they have also greatly affected the products market performance. Study of different grades and 380 modeling style and the era fashion trends, finding its intrinsic relationship For enterprise new product development is of great significance. The article briefly introduced China Bus modeling development and the status quo, a more detailed explanation of the whole bus, Interior and Local modeling and modeling technology should pay attention to the issue. Passenger train on the meaning of Design and evaluation criteria. Plan outlines the concept, the effect map, model passenger cars in the design process modeling role. In the shape of the car design process, compatible with the disabled seating modeling features, the Bus appearance, Interior design and some of the details on both innovation and the adoption of 3D CAD software in the design process demonstrated. By modeling features of the bus, the bus market grasp the shape of demand, improve product competitiveness on the market. KEY WORD: automobile, styling, design, CAD, disabledWHEELCHAIR TIEDOWN AND OCCUPANT RESTRAINT SYSTEMS FOR USE MOTOR VEHICLES
Foreword—For people with disabilities who are unable to transfer from their wheelchairs when traveling in motor vehicles, the wheelchair must serve as the vehicle seat. This usually means that the occupant restraint system installed by the vehicle manufacturer cannot be used to provide protection in a crash. In addition, the wheelchair must be secured to the vehicle so that it does not impose forces on its occupant and/or become a hazard to other vehicle occupants in a collision or sudden vehicle maneuver. Providing occupant protection for the wheelchair-seated occupant, therefore, requires that aftermarket equipment be installed to secure the wheelchair and restrain the wheelchair user.
This Recommended Practice applies to the design and performance of motor-vehicle adaptive equipment referred to as wheelchair tiedown and occupant restraint system or WTODS. It is the purpose of this document to encourage the design, testing, installation, and use of WTODS equipment that will provide effective wheelchair securement and occupant restraint in a frontal collision, and that will be comparable in crash performance to seat securement and occupant restraint systems provided by the vehicle manufacturer. While the primary concern is to reduce the potential for injury to wheelchair-seated occupants involved in a frontal vehicle crash, it is anticipated that achievement of improved occupant protection will also result in increased driver and passenger safety and comfort during normal travel. The provisions of this document should not be used to discourage people with disabilities using motor vehicle transportation or to limit access to, and availability of, motor vehicle transportation to wheelchair users.
Since manufacturers of WTORS are generally not able to control or specify the end use of their products, the 48-km/h, 20-g sled impact test specified in Appendix A is intended to qualify WTORS for use in vehicles with a gross vehicle weight of less than 7000kg. In larger vehicles, it may be possible to provide safe transportation using WTORS that do not comply with the level of crash severity used in this document.
As with any vehicle seat, the wheelchair is an important component of the occupant protection system, and also contributes to the stability and comfort of the wheelchair-seated occupant during normal travel. Design and performance of wheelchairs used as seats in motor vehicles is addressed in a separate, but related, ANSI/RESNA Standard now under development.
Design Requirements
1. Complete WTORS--WTORS shall:
a. Be for use with only one wheelchair and one occupant at a time .
b. Not require components of wheelchair tiedowns and occupant restraints to pass through the
wheels of a wheelchair .
c. Provide for release of both the wheelchair and the occupant within 60s by a single attendant or
wheelchair user without the use of tools .
d. Not require removal of wheelchair frame material, drilling into the wheelchair frame,
deformation of the wheelchair, welding, or the use of an adhesive process, during installation,
unless the WTORS is intended for a srecific wheelchair and the modifications are approved by
the wheelchair manufacturer .
e. Once installed, be operable without tools .
f. Include only hardware and fittings that are permanently connected to the WTORS or a
WTORS subassembly .
g. Be designed to prevent unintentional loosening of all threaded fasteners .
h. Include a manual override in case of power failure for any power-operated mechanisms of
tiedowns or restraints .
i. Include anchorage fasteners and hardware, and/or specifications for such hardware, that are
based on the material, size, and quantity of anchorage fasteners used in the simulated frontal
inpact test of Appendix A .
2. Wheelchair Tiedowns--Wheelchair tiedowns and tiedown components shall:
a. Not depend on the wheelchair brakes .
b. Be designed so that securement of the wheelchair is accomplished by the tiedown only and not
by the occupant restraints .
c. Provide a means to eliminate free movement of the wheelchair without the use of tools .
d. If the WTORS includes a four-point strap -type tiedown, each strap assembly shall provide for
manual adjustment in length without the use of tools, such that the adjustment ranges of front
and rear straps enable achieving the minimum and maximum lengths indicated in Table 1, with
at least 25 mm of webbing extending from the adjustment mechanisms.
TABLE 1--MIMIMUM ADJUSTMENT RANGES FOR FOUR-POINT TIEDOWN STRAPS:
Strap Assembly Location Mimimum Length mm (in) Maximum Length mm (in)
Rear 485(19) 740(29)
Front 410(16) 710(28)
e. Have securement-point end fittings of four-point tiedowns that are compatible with the
securement-point structural member of the surrogate wheelchair illustrated in Figure E4 .
f. Include a device to indicate, by visual or auditory means, when a docking-type tiedown is
properly engaged .
3. Occupant Restraints--WTORS shall either be designed to use the vehicle OEM passenger or
driver restraint, or shall include an occupant restraint that complies with the following
requirements:
3.1.The occupant restraint portion of the WTORS shall include both pelvic and upper torso restraints .
3.2 Occupant restraints may be designed to anchor directly to the vehicle, to components of the wheelchair tiedown, or to tiedown components fastened to the wheelchair. Occupant restraints shall not be designed with anchorages that rely on the transmission of restraint loads through the wheelchair structure unless the WTORS is designed for a specific wheelchair and the WTORS meets the requirements of 6.2 when the combination of wheelchair and WTORS is tested according to Appendix A .
3.3 The lengths of pelvic and upper torso restraints shall be manually adjustable without the use of tools .
3.4 When the WTORS is set up and measured as specified in Appendix B, pelvic restraints and, if applicable, their anchor points or guide points, shall:
a. Achieve side-view projected angles that fall within the zone shown in Figure 4b .
b. Achieve projected rear-view angles and locations within the zones shown in Figure 4a .
c. Provide sufficient length adjustment to allow the pelvic restraint, measured from anchor point to anchor point, to be both increased and decreased by 200 mm with at least 25 mm of webbing extending through the restraint end fittings at all times .
3.5 When the WTORS is set up and measured as specified in Appendix B, upper torso restraints shall provide for sufficient length adjustment to extend an additional 200 mm, and shorten by 300 mm, with at least 25 mm of webbing extending through the restraint end fittings at all times .
4(a) 4(b)
FIGURE 4
NOTE—Note that angles indicated are obtained by projecting the angle of the pelvic restraint onto a vertical plane to the wheelchair reference plane (side view), or onto a vertical plane that is perpendicular to the wheelchair reference plane (rear view) .
3.6 For WTORS that include upper-anchor points or upper-guide support structures for shoulder or harness restraints, the locations of these anchor points or supporting structures shall:
a. Be sufficiently adjustable in height to be located at or above the shoulder levels of the intended user .
b. Be located at least 1100 mm above the wheelchair ground plane so as to be near or above the shoulder height of wheelchair seated occupants .
NOTE1—The anchor point may be located below 1100 mm if an upper-guide support is located at or above 1100 mm .
NOTE2—Although FMVSS 210 allows for the upper torso restraint anchor points to be located a significant distance below the occupant’s shoulder level, such locations are considered to be undersirable and not in compliance with this document since they could result in downward loading on the occupant that can produce spinal injuries .
3.7 The junction of the shoulder and pelvic restraints of three-point restraints shall be located not less than 150 mm from the ATD centerline when installed as specified in Appendix B .
3.8 An airbag shall be used only as a supplementary occupant restraint in conjunction with a wheelchair tiedown and belt-type occupant restraint that comply with the requirements of this document .
3.9 Performance of the WTORS shall not depend on an airbag to comply with this document .
4. Test Report—The WTORS manufacturer shall have documentation on file and available that includes:
4.1 Statements concerning compliance of the WTORS with the Design Requirements of 4.2 through 4.3 including:
a. Minimum and maximum tiedown strap lengths of four-point strap tiedowns in comparison to the requirements of Table 1 .
b. Whether the end-fitting geometry of four-point tiedowns is compatible with the end-fitting geometry of Figure E4 .
c. The angle of pelvic restraints when setup according to Appendix B .
d. The range of length adjustment in the pelvic restraint when set up and measured as specified in Appendix B .
e. The range of length adjustment in the upper-torso restraints when set up and measured as specified in Appendix B .
f. The height or height-adjustment range of upper-torso restraint upper-anchor upper-guide support provided with the WTORS, and a statement of whether the height complies with 4.3.6 .
g. The distance of the pelvic/shoulder restraint interface of three-point restraints from the ATD centerline when set up and measured according to Appendix B .
4.2 Statements concerning compliance with the requirements of :
a. FMVSS 209 as specified in Table 2 .
b. FMVSS 302 concerning flammability of WTORS webbing material .
4.3 Statements concerning compliance with the Frontal Impact Test of Appendix A, including :
a. A description of the test facility, including the type of impact simulated, instrumentation and signal processing techniques, the frame speed for each film and/or video produced, methods for measuring sled velocity change and deceleration, methods used to measure ATD and test wheelchair excursions, and the accuracy of excursion measurements .
b. A statement of whether the sled deceleration pulse complied with A.4.3 and Figure A1, including the duration of the pulse, and the number of cumulative milliseconds that the deceleration exceeded 15 g and 20 g .
c. The measured or calculated value of the test delta V .
d. A full identification of the WTORS, anchorage fasteners, test wheelchair, and ATD used .
e. Pretest measurements documenting the locations of all WTORS anchorages relative to point P of the test wheelchair .
f. The side-view, front-view, and rear-view projected angles of all tiedown straps and pelvic restraints relative to the horizontal or vertical, as appropriate .
g. A description of the test setup including a statement about any parts or fasteners used ih the test that were not provided by the WTORS manufacturer .
h. Whether the ATD remained in the test wheelchair .
i. Whether the test wheelchair remained on the test platform .
j. The change in the orientation of the test wheelchair reference plane, if measurable, in comparison with the initial test orientation .
k. Identification of any WTORS load-carrying parts that showed visible signs of tearing, fragmentation, fracture, or complete failure, that were not designed to rear or fail in the manner noted .
l. The peak horizontal excursions specified in 6.2.d, and whether any of the excursions exceeded the limits in Table 3 of this document .
m. A statement as to whether the ATD and test wheelchair could be released from the WTORS without the use of tools .
n. A statement as to whether the ATD was loaded by the test wheelchair based on the results of the calculation in 6.2.e .
4.4 Statements concerning compliance of appropriate WTORS components with the Test for Partial Engagement of Appendix C, including :
a. Full identification of the WTORS system and the securement and anchorage components tested .
b. A description, including photographs if necessary, of the manner of each partial engagement tested .
c. A description of the procedure used to apply the separating force .
d. The results of each test, i.e., the securement or anchorage mechanism either separated or remained engaged .
4.5 Statements concerning compliance of any strap assemblies of wheelchair tiedowns with the Test for Webbing Slippage at Adjustment Devices of Appendix D, including :
a. Full identification of the WTORS system, type of webbing, and each adjustment device tested .
b. A description of the test apparatus and procedure .
c. The amount of webbing slippage at each adjustment device tested .
d. A statement as to whether the 25 mm limit was exceeded for each adjustment device tested .
e. A statement as to whether all adjustment devices of the wheelchair tiedown portion the WTORS passed the test .
5. Definitions—For the purposes of this document, the following definitions apply:
5.1 Anchorage—An assembly of hardware and fittings by which loads are transferred directly from the wheelchair tiedown to the vehicle or from the occupant restraint to the vehicle, wheelchair, wheelchair tiedown, or vehicle seat base .
5.2 Anchor Point—A point (area) on a vehicle, wheelchair, wheelchair tiedown, or vehicle seat base to which an anchorage is attached .
5.3 ANSI—Abbreviation for American National Standards Institute .
5.4 Anthropomorphic Test Device (ATD) –An articulated analog of the human body used to simulate a motor-vehicle occupant in a crash environment .
5.5 Automatic-Locking Retractor—A retractor incorporating adjustment by means of a positive self-locking mechanism which is capable, when locked, of withstanding restraint forces (from SAE J1834) .
5.6 Back Restraint—A device or system intended to limit rearward movement of the occupant by providing support to the back of the torso .
5.7 Belt—A length of energy-absorbing webbing material used as part of an occupant restraint .
5.8 Docking-Type Tiedown—A wheelchair securement device whose engagement is initiated as a result of the wheelchair rolling into the proper position .
5.9 Emergency-Locking Retractor—A retractor incorporating adjustment hardware by means of a locking mechanism that is activated by vehicle acceleration, webbing movement relative to the vehicle, or automatic action during an emergency, and that is capable, when locked, of withstanding restraint forces (from SAE J1834) .
5.10 End Fitting—Anchorage and securement hardware to which tiedown and occupant restraint webbing is fastened and which attaches directly to the anchor points and securement points on the wheelchair, tiedown system, or vehicle .
5.11 Fasteners—Devices used to secure, by mechanical means, other components or parts in place .
Note—These include, but are not limited to:bolts, nuts, screws, pins, rivets, and clamps .
5.12 Forward Facing—Orientation in which the wheelchair-seated occupant faces the front of the vehicle with the wheelchair reference plane within 10 degrees of the longitudinal axis of the vehicle .
5.13 Four-Point Tiedown—A wheelchair tiedown system that attaches to the wheelchair frame at four separate points and anchors to the vehicle at four separate anchor points .
Note—The typical four-point tiedown system uses four tiedown straps, with two attached to the front portion of the wheelchair and two attached to the rear portion .
5.14 Harness—An occupant restraint consisting of at least one belt designed to provide pelvic restraint and two shoulder or torso belts that apply forces to both shoulders .
5.15 Head Restraint—A device intended to limit rearward displacement of the occupant’s head .
5.16 Impact Simulator—A device for accelerating, decelerating, or a combination of decelerating and accelerating, a section of a vehicle or simulated vehicle structures, including instrumentation for measuring pertinent data (from SAE J850) .
5.17 Impact Sled—That part of an impact simulator on which components can be mounted for impact testing .
5.18 Independent Occupant Restraint—An occupant restraint that anchors directly to the vehicle or vehicle anchored components that are separate from the wheelchair and wheelchair tiedown .
Note—This is also known as a parallel restraint system .
5.19 Integrated Occupant Restraint—An occupant restraint for which the anchor points for the pelvic-restraint, or both pelvic and shoulder- restraints, are located on the wheelchair, or on tiedown components not fastened to the vehicle .
5.20 Occupant Restraint Anchorage—An assembly of hardware and fittings by which loads are transferred directly from the occupant restraint to the vehicle, wheelchair, wheelchair tiedown, or vehicle seat dase .
5.21 Occupant Restraint—A system or device for restraining the occupant in a vehicle to prevent or minimize contact with the vehicle interior components, and to prevent ejection during a crash (from SAE J2094) .
5.22 OEM—Abbreviation for Original Equipment Manufacturer .
5.23 Pelvic Restraint—That portion of a seat-belt assembly intended to limit movement of the pelvis .
Note—Other terms with similar meaning are lap belt, lap restraint, and lower torso restraint .
5.24 Point P—A reference point that lies at the cross-sectional center of a 100 mm diameter disc positioned with the longitudinal axis perpendicular to the wheelchair reference plane, such that the curved surface of the disc contacts with the backrest and the upper surface of the seat .
5.25 Postural Support—A component used to support a person in a desired position, but that is not usually intended to provide occupant restraint in a vehicle impact .
5.26 Securement Hardware—End fittings of a wheelchair tiedown system that connect to the wheelchair .
5.27 Securement Point—Location on the wheelchair frame to which a wheelchair tiedown end fitting connects .
5.28 Strap—A length of webbing material used as a part of a wheelchair tiedown .
5.29 Surrogate Wheelchair—A rigid, reusable device used to simulate a wheelchair for the purpose of testing a WTORS .
5.30 SWC—Abbreviation for surrogate wheelchair .
5.31 Test Wheelchair—A production, prototype, or surrogate wheelchair used to conduct tests specified in this document .
5.32 Wheelchair Tiedown Anchorage—An assembly of hardware and fittings by which loads are transferred directly from the wheelchair tiedown to the vehicle .
5.33 WTORS—Abbreviation for wheelchair tiedown and occupant restraint system .