升降机外文翻译-高空作业升降机的动态特征和分析【中文3650字】【PDF+中文WORD】,中文3650字,PDF+中文WORD,升降机,外文,翻译,高空作业,动态,特征,分析,中文,3650,PDF,WORD
DYNAMIC CHARACTERJZATION AND ANALYSIS OF AERJAL LIFTS
A Thesis Presented to
The Academic Faculty by
Eileen C. Hernandez
In Partial Ful丑llment
of the Rβquirements for the Degree Master of Science in the
George W. Woodruff School of Mechanical Engineering
Georgia Institute of Technology December 2012
SUMMARY
Aerial lifts 町e used to elevate people and material to high heights. There 町e 皿皿y different types of aerial lifts which have vastly different dyn缸nics characteristics. Thus, a new categorization for aerial lifts w出created and organizes them by their kinematics. Many accidents occur while using aerial lifts. Haz町ds of aerial lifts and current solutions to those hazards were reviewed to understand the causes of the accidents. Some major accidents are due to the compl缸 dynamics and flexibility of a启Z划 lifts, such as oscillations and tip-overs. Oscillations of full-size a町ial lifts were experimenta』ly tested to determine 仕equencies in different configurations. Machine-motion induced oscillations of an articulati卫g aerial lift were simulated and analyzed for both non-overcenter and overcenter configurations. fuput shaping was used to achieve reduction in machine-皿otion induced oscillations. Tip-over stability margin was used to simulate and analyze the stability of both non-overcenter and overcenter configurations. The effect of increased platform m回s on tip-over stability m町gin W出also analyzed. The results in this thesis are a categorization of aerial lifts including their hazards and methods of reducing those hazards, an experimental verification of the dyna皿ic response of full-size aeria』 lifts, a fully dynamic tip-over prediction model of double-boom articulating aerial lift by applying flexibility in the joints and realistic velocity profiles, and a detailed study of the dynamics of a double-boom articulating aerial lift.
Xl
CHAPTER I
INTRODUCTION
There are many ways people reach high heights to work on buildings, trees, airplanes, and other tall structures. In many cases, aerial lifts 缸e used to provide the desired height and work environment. Aerial work lifts, like the one shown in Figure 1, provide many necess町y benefits to users that need an elevated work platform. However, with those benefits come significant hazards.
“According to the U.S. Bureau of Labor Statistics about 26 construction workers die each ye町 from using aerial lifts. Approximately 70% involve boom supported lifts, such as bucket trucks and cherry pickers; 25% of the other
deaths involve scissor lifts” ［ 1].
／／
Figure 1: An Altec truck-mounted articulated aerial lift working on electrical lines.
1
From 也ese statistica.1. facts two ma.in challeng四can be infeITed. The 位就 challenge is deter回国ng how to reduce fatalities that occur when using aerial lifts. Tb创甘：ore, there is a n四d to identi岛r 也e most co皿mon hazards of 树总al lifts and how they occur. The second
challenge is widersta.nding the 祖erent aerial work lifts (i息 bucket trucks, cbeny pick，棚，
SC凶sor lifts, etc.), their respective b相ards, and m创hods to reduce those h拙ards. Before detennilling how to redu,创 制iden馅，it is 国1portant to understand 也e different 槌rial 且她 well enough to develop po协ntial solutions that could be applied to the 嗣ria.l work lifts under consideration.
1.1 Desc时俐 ” and Categoriza锐on of Ae付 t L梆s
Aerie.I work lifts have e. wide range of a.ppearan臼s; however, all of them, a.re 四ed to position people high 凶the air [1]. Different m础.anisms m四创 始 阳form this 凶ing motion.
The kinematic structur程 ie what 部，para也·ee difl趾·ent typ剧 f aerie.I work lifts. The 缸'St
distinguishing factor 础 ng 棉对al lifts is 必rectionality of 白白motion: i) only vertical or, 总） Vi ical and horizontal，掘础 wn in Figure 2. A S部ond catego归ation is 也.e method used to elev在te the work platform. 四ere are thr锦 different m础 ds of elevation within each
位ectional ca.te静思 Ve民ic创凶s use：斗 部i筋 z，总.） ve约iβal mast，础d i均 pulley Sy侃锢s.
’
Lifts performing v的ical and horizontal motion use: i) tel制叩ic, ii) a.rticul就问，and 诅） te1锦oopic articulating. The final major way to dilferentia:悔 aerial 1出s is by their a.b山在y or 国功迫ity to drive on the ground while elevated.
3
Jf
，，
，
，
，
，，
，
····－
4
一
，
‘ ’川 ，
，
1也·u·····a
（碍 nly vertical motion
（均 Vertical and ho归ontal motion
Figure 2: Two Categori郁 f Aerial Li成 Motion.
Mobility while elevat.ed depends on the b副e ofthe aeriAl lift. L也a 份1at are able 协 缸ive while i总 部eration have a cab base to hold the power supply 仰d削略 Figure 3(a） 凶础 example of a cab-base lift. Ifa lift b锦a skeletal struct山珍 for the base or is 也ruck-mounted, then the aeria.I lift is unable to drive while elevat创.A1l 姐ample of 8ll immobile aerial lift with a skeletal b毗凶shown in R脚跟 3{b).
(a) Genie Z-80 mobile cab base (b) Genie TZ-34／到回mobile telescopic tele阂 ，pie 恼ticulating lift articulating lift with an skeletal base
Figure 3: Examples of mobile 1and immobile 辅rill』 lifts a.
Overall, moat aeri剑 work 凶S 锦n be 以aced 恒 ne of 出.e following 胆 d翩翩：
1. Sci”。r L出a
2. Verti恼J Mast L出8
3. Pulley Lifts
a τelesc。p沁 Lifts
、
5. Articula.ting Lifts
6. τ lesco以c Articulating Lifts
Scissor 崎S, V础ica.I m崎t 溢缸，and pulley li岛sperform only v础ica.I motion. τ副阁copic lifu:I 馆也ic叫.a.t坠g lifu:I, and teleacopic articulating lifts perform verti凶J and horizontal mo tion. Each cate伊叩h础varia悦 ns that c础 r c础not drive while elevated. By including 辅ria.I lifts’ mobility or i.mm抽出ty while el剧时时，th.e complete categorizat沁n of a衍凶险加 is giv， in Table 1.
1http://www.gemelilt.com/en/prod.uct呐何:.equipmeutfb即胁／iDdex.h阳
'http：／／ 同肌阴副iii.四m/en/prod.ucts/new咱，quipmeut/traile?-mountec弘·boo皿／md帆htm
τ'he power supply used by aerial lifts do四not depend on the directionality of itsmotion. It depends on the intended work environment. Two different work environments for aerial l出s are: i) indoor 皿d ii) outdoor environments. Indoor environments re的rict the power supplies to those that do not emit 但:ha.ust such as electric, manual, battery, and sometim四 a hybrid that uses E翩 r diesel outdoors and electricity or b也.ttery indoors. Outdoor en- vironments 町e not 田restrictive as indoors; thus, all power suppli田can be used. Other options that apply to all aerial lifts 町e insulation for electrical work and/or reinforced heavy duty for industrial work.
Some companies that 町e well lmown for aerial work lifts include：τer眩 Ni缸yli丘 Alt钮，
JLG, Haulotte, R刷.chm嗣ter, Skyjack, Snorkel, E血的，Versalift, MLE Man Li晶 Manuf胁 tur国g Co., and Hi-Rea.ch. MLE Man Li丘 Manufacturing Co. sp臼ializ由国皿a.king custom aerial lifts such 回clean room lifts and pedestal mount man-lifts. Bridge Across Specialties,
Wes也 Co届t Under Bridge Platforms, and Pal.finger specialize in truck-mounted aerial work l监s capable of accessing beneath bridges for rep膛，皿aintena.nce, and 且spection，剧由佣n in Figure 4.
Figure 4: Palfinger’s vehicle-mounted bridge 皿spection l出performing 皿aintenance under a bridge. 14
14htt回：／／市附w.阴脑血.ger.oom/en-US/usa/products/
9
1.1.1 Verti恤l Lifts
V目世cal 凶s are 11Plit into thr喃wbl蜘ti()Illj: IICis盹r lift8, vertical 国剧t lifts 阻d pulley 蹄，Sci阂 r lift.a a.re 陆ntilied by th席四que structure that r酬mbles mul句，le scis阳m retra.c出sto redu曲M梆础d 8X阴.nd问to m翩翩e heigl拢 幽幽翩 in Figure 5.
Figure 5: Genie GS”1530 刷刷 r lift with 铀b b割e.15
W此icsl. m翩 翩e ha晦 田1且］ti 阳ti 但a a篇 either fit in.side 惆e 础 由er or equal 鹏也io惚也at slide up agAilJBt one a:na也er to 总翩翩lheight. A且但.11111ple of a verti锦l m础 lift Iss』own InFi .ire 6. Both 能lssor lifts and var舶d mast lifts have 也e option of mob心lty while ell!V就ed. If the lift h剧 a cab bl!i酶，lib the 咽ne i且 F地归嗡 5，他刷出e lift c皿 dri喃
W祖ile d回事协d.
Pulley lifts 1幽也e comm仙”ill！’＼ ”脚，m t.oelev&te 他e locatlon 。.fthe响出且g plat阳m.
Cun回街 th晴 哑ly known pulley H岛倒乱ilable has & sb,let侃 而ucture 如‘b剧院 A pulley 溢ft 创地not be mobile W汹le ele喃，ted b帽刷晶e it b嗣a d岱坊ta! struct植re for a b制峙 楠ab.own in Fi .Ire 7.
All var悦阳I lifts 曲n be us创帆1tdoore. Due to t』.e small bodi帽 and fo的prints of vertical
溢疵，they c陆al阳all be uaed indoors 棉long 础 they a.re not 伊a or di回el p阳惚ed.
抽油嚣，fl曹帽嘟由她 ；叫.事 曲础':t.11/'IJ8W·啪”回国国叫陆／m幅幅
Figure 6: Haulotte immobile vertical mast lift.6
Figure 7: JLG’s Liftpod that uses a pulley system.7
1.1.2 Vertical and Horizontal Lifts
Vertical and horizontal lifts are comprised of: articulating lifts, telescopic lifts, and telescopic articulating lifts. All vertical and horizontal motion aerial lifts achieve lifting by pivoting their boom(s), represented 回 a dashed red line in Figure 2(b). The booms of a vertical and horizontal aβrial lift are commonly referred to as the arm of the aerial lift. In addition, vertical and horizontal motion aerial lifts rotate at the base to provide access in all directions.
Figure 8(a) shows a rotation at the base around the vertical axis of an aerial lift commonly referred to as a slew movement. Figure 8(b) shows a rotation around a horizontal 缸is of an aerial lift commonly referred to as a luffing moveme时，which is the result from pivoting their booms.
Base
＋
1
TW
」
TL
(a) Slewing motion (overhead view) (b) Luffing motion (side view) Figure 8: Movements of vertical and horizontal motion aerial lifts.
An articulating aerial lift has two or more hinged boom sections that pivot at the hinges to elevate the working platform [1]. Figure 9 shows a truck-mounted articulating aerial lift with multiple boom sections.
Figure 9: Altec articulating aerial lift.
Aerial lifts with only one hinged boom section may be telescopic lifts or just a one boom aerial lift. Telescopic lifts can slew, luff, and their boom length can increase due to the
Figure 10: Genie S-60’sτ'ra.x cab base t.elesc呻ic aerial lift. 16
multiple s出tions wi也in e. boom. The c配，b-mount.ed telescopic li丘 in Figure 10 b幅a.sm刻ler
”ction extendi.Dg out of the top pa.rt of 出怠 boom to i.Dcrease the boom length.
白lesc ，pie 缸锐cul.at凶恶 aer圳 ］出s are 馆ti，.ua创ng lifts and t.el，邻copie 坦fts comb丽时－ Teleacopic 彼ticulating lifts have multiple hinged boom 锦ctior邸 佣a slew, luff 础d 也heir
booms c阳were回e in length. F泡出e 11sho· 植 树rial 时b with multiple booms and its
upper boom can 部pa.nd iD Ieng协 due to the tel倒copic sectio出．
Fig11. 1re 11: Ge皿e Z-60β4 c也b b嗣e telescopic a.r秘culat凶g lift. 10
V创tical. and horizontal. lifts ca.n. be mobile or immobile w.垣le elevated dependi吨 upon the base of the aerial lift. Vi仪tical a.nd ho巾，ntal aerial lifts have three base optioDS:
1ehttp://www.阴汹汹倒也／en/prod.ucts／阻何呻quipment/boom-凶s／剧创啕ic-b倒四／irJm!x.比m
Flgu阳12: G幽le TZ-50 Ill .e. 伯国letal b创始 创皿白布，le 世tlct且at:!ng Ila. 11
sbletal 铺b-mo “ z肌ck-mo咽ted. 章bletal ba鹏翩翩草草莓铺皿ot 命柄 始le刚刚－
10
HO嗣'
V睡 they 制品b。国“InIndoor 耐 outdoor 西'Vin:坦国皑白、描shov.'ll 忠民gure 12.
岱u必血咱也med 崎r!al 阳剧啤be 血 blle W汹le tal脚d. inad晦过曲 国烛呻翩翩ted
棚刘 w帽k Ii:民局 翩 凰盹 础 pti铺 始 祖d时炫 制闹四皿剧幅 due 抽 r,ia惊切led M抽幅画 and
回hw.st 臼瞄“by in阳回倒四，bn.stlon 剧颂阳帽 ’h岱咽 也”“翩刷 W阳k 凶a are com
m.only 翩 d 伽 毗do,世 appllc,略 归队 A tniclc-mou国 崎rialIi袋也鹉 ii.as 柿 自出且巅峰 阳血a is oommoazy- lalow'll 翩‘也阳军y 斜d酶 础 shO'WD. ill民阴e 13. 臼tlr'lY 斜cbn w脚 flfflt used 伊协aril.y in on:ham!! 如 斜cit frul幅 b翩翩 they 幽幽铀!lily 仿vale and !0-
We ”阴阳栩 如 the 耐峙 t 俗e txw:k, ellowiDg quiclt 辄阳帽如在he prod飞隅.s国丘配阳
”'Odu崎 in 帽cluu:ds， 峙S Nlld tale协 ＂＂pol帽”抽烟g dist幽础 前 “四阳d he!庐锐 岱e曲时，cheny p!cl
收藏