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畢業(yè)設計(論文)外文資料翻譯
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AGRICULTURAL MECHANIZATION ASIA，AFRICA AND LATIN AMERICA 2004 VOL.35 NO.1
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附錄C：外文翻譯
用于芒果收獲的變位機的發(fā)展和測試
R.A.Gupta R.M.Satasiya Pramod Mohnot N.K.Gontia
摘要為了減少在收獲芒果時的損失，并保證水果質(zhì)量，一種機掛式變位機在Gujiarant農(nóng)業(yè)大學被研制出來，并進行了測試。在操作過程中發(fā)現(xiàn)，由變位機采下的芒果都是成熟的，而且有10~20mm長的葉柄，沒有樹葉粘在水果表面，且沒有任何損傷。在果園中用變位機，收獲時每棵樹可以節(jié)省RS1000。
引言
芒果是水果之王，在水果商業(yè)中有著重要的地位。印度是最大的芒果生產(chǎn)國和出口國。在Gujiarat，每年有57000公頃的芒果種植面積，生產(chǎn)大約382000噸的芒果。近來出口和種植的優(yōu)良品種遍布全國，主要集中在Gujiarat的南部和Saurashtra地區(qū)。水果的質(zhì)量主要取決于它的成熟期。
在印度，收割芒果大多由手工完成。主要的工具就是鐮刀、剪刀、刀片和吊籃。就采芒果來說，利用一些輕巧機械比用手采摘或搖樹的方法可降低勞動強度。這樣還可以避免果實的損傷、樹枝折斷等后果。果實碰傷和損壞是非常嚴重的問題。果實不允許直接從樹上摔到地上，因為在包裝水果時，受傷的水果會損害其他好的水果。芒果釆摘時留有8~10mm的葉柄，是為了在采的時候避免樹汁留在芒果表面而形成污點，這樣水果就不容易腐蝕，也就避免產(chǎn)生其它保存問題。
Assam研究采摘水果的設備，人工操作的裝置都是用鐮刀或刀片將水果一個一個釆摘后再包裝，這樣的裝置適合大小和高度差不多的水果。另一種機械是搖樹裝置，這種裝置適合比較硬的水果。Brown和Schertz也在研究這種機械采摘裝置，并且曾宣布說用該裝置采摘的水果比人工采摘的水果有更多的損傷，如裂開、表面和內(nèi)部碰傷、表面創(chuàng)傷等。
Gujarat農(nóng)業(yè)大學發(fā)明出一種先進的釆摘裝置。跟其它采摘裝置相比，它有一個較好的工作情況。采下的水果大約有90%帶有10~20mm長的葉柄，特別符合出口要求。人工釆摘水果的時候利用一種輔助的機械變位機，可以讓人站在上面用剪刀采摘。因為才釆摘時離水果較近，可以采那些成熟的水果而不讓其受傷害。因此機掛式液壓變位機的發(fā)展和測試是必要的。
取材和方法
機器初步信息的設計主要與樹的特征有關(guān)，要確保及其在果園里有足夠的活動空間和能力。樹上的水果是分散的，可以采到的水果百分率見表1到3。機器的高度和底盤的尺寸也要仔細考慮。利用以上的信息，設計和發(fā)明的液壓變位機可以用來采芒果和其他水果。同樣也要考慮安全因素。要想減少機器的花費，可以通過減少移動部分的數(shù)量來實現(xiàn)。
機器主要由一個底盤、三點懸掛裝置、液壓千斤頂和護圈組成。底座由50*50*6的角鋼制成，機座的組成及尺寸見圖1。可承受2噸重的液壓千斤頂有兩個氣缸，通過40mm長的銷安裝在機座的中心，并通過兩塊金屬板焊接在機座和液壓千斤頂下端。液壓千斤頂上面的一端由三根支撐桿支撐著。類似的，活塞的上端通過螺母和螺栓固定在法蘭盤上。為了使變位機的高度可調(diào)，就要將1mm長的、可伸長的100mm的軟管用法蘭盤、螺母、螺栓連接在活塞的上端。管子上端通過相同尺寸（20*20cm)的法蘭盤焊接在防護罩上。防護罩由角鋼、可鑄鋼板和木板構(gòu)成。機座的護圈由角鋼制成，尺寸為92*76*70cm。防護圈的底座由木板支撐。底部的一邊由一個55*47cm的開口，可以使采摘者站到變位機上。變位機上四邊是可以折疊的，當機器移動時，其高度可以調(diào)節(jié)到最低。
要操作該機械裝置，要通過液壓千斤頂?shù)娜c聯(lián)動裝置和軟管連接到液壓系統(tǒng)的牽引機上。防護罩升至伸長部分的頂部，四邊折疊。機械裝置被運送到指定果園，在釆摘的時候，裝置要放在地上，釆摘者帶剪刀和紙箱站在防護罩下的地板上。為了安全起見，防護罩的四邊都應該有護欄，由鉤銷鉸接在機座上。牽引機的液壓系統(tǒng)舉起防護罩，一旦閥打開，油在壓力作用下由軟管進入千斤頂，推動千斤頂?shù)幕钊?，從而使防護罩上升。當達到所需要的高度，關(guān)閉閥，使其停止上升。采摘者可以在很近的距離內(nèi)采水果。只采那些成熟的水果放入紙箱內(nèi)。當紙箱裝滿時，可以將其送到地上。一些水果長在樹頂上，采摘者可以用手工采摘工具。
圖2.變位機的動力來源 圖3.使用者用變位機采摘芒果
測試
果樹以12*12m的距離種植。用35馬力的HMT牽引機來做實驗。有經(jīng)驗的工作人員可以站在上面釆水果。在機械裝置的測試期間，一些重要的觀察，比如每小時采摘水果的數(shù)量、質(zhì)量、葉柄平均長度、明顯損害率、水果的保存期限等。
采摘的費用主要由勞動力等。該裝置需要兩個工作人員，一個采一個接。老練的工人得到的報酬比經(jīng)驗少的工人多。
為了估計水果質(zhì)量的損失，將兩個塑料袋放在室溫條件下，將采下的水果按葉柄排放整齊，每隔三天紀錄一下。第七天，用傳統(tǒng)方法采下的水果有變質(zhì)的征兆，將它們從袋中取出。
結(jié)果與討論
1、收割量
機器試用所記錄的結(jié)果見表4。用變位機平均每小時可采水果 360個，而當?shù)氐尼娬呙啃r可采377個。因為變位機的上升和下降都需要時間，在1967年，Schertz也報道過相似的結(jié)果。在研究過程中，他發(fā)現(xiàn)站在地上采水果的效率要比站在變位機上的效率高。
2、葉柄長度
葉柄地起限定作用的一個因素。用變位機采下的水果，其葉柄一般長20cm,而用傳統(tǒng)方法采下的水果，其葉柄長度一般不一樣，有的甚至超過50cm，但有的卻又沒有葉柄。這些水果的賣相不好，果農(nóng)必須以低價才能出售。此外，研究表明沒有葉柄的水果會使柄末端發(fā)生腐爛，而有柄的水果會延長它的成熟期。所以使水果有10~20cm 的葉柄是必要的。
3、表面損傷
水果表面損傷是由樹枝造成的，這種損傷在用變位機采下的水果上是沒有的，因為所有的水果都有葉柄。而用傳統(tǒng)方法采下的水果11.11%有表面損傷。
4、水果的存放期
這個涉及到采下的水果在沒有任何持續(xù)損害的情況下可以被存放的期限。保存的期限與采摘的方法有關(guān)。用變位機采下的水果可以完好無損的保存9天，水果仍然有完好的表面和誘人的顏色。而用傳統(tǒng)方法采下的水果在第七天會出現(xiàn)黑的斑點。如果水果受到傷害或呼吸作用受到限制，微生物很容易侵入水果內(nèi)部，所以應該細心的避免各種傷害，延長水果的保存期限。
表4.比較用不同方法采摘的水果的測試
5、釆摘的成本
表4表明，用變位機的采摘成本為每噸RS2783，而用傳統(tǒng)方法采摘的成本大約每噸RS368。前者的成本雖然高，但水果質(zhì)量好，沒有一個會因為損害或腐爛而造成損失，而后者雖然成本低，但一般都有10~15%的損失率。由于10%的損失相當于1000kg最終只有900kg可以賣，如果每千克以RS17.50出售，可以得到RS15750。而用變位機采下的水果可以高價出售，每千克可賣到RS20，共可以得到RS20000，扣除所需要的操作費用RS2415，所得到的利潤為RS1835/噸。換句話說，釆用變位機采水果，每棵樹可以節(jié)省RS900。
6、質(zhì)量的減少
關(guān)于對plw的觀察，在實驗室每隔三天的記錄見表5。采用傳統(tǒng)方法采摘的水果在第3天、第6天、第9天其質(zhì)量逐漸減輕，其損失率為15.88%，而采用變位機的損失率為13.27%。
表5.水果質(zhì)量的損失
結(jié)論
從以上的研究中我們可以得出以下結(jié)論：
1、利用變位機采下的水果沒有機械損傷，而且都是熟的。
2、采下的水果100%的都有l(wèi)~2cm的葉柄，沒有樹葉，并且保持白色的亮度。
3、存放和運輸?shù)膿p失可以減到最低程度。
4、由于釆下的水果質(zhì)量較好，每棵樹的凈利潤為RS1000。
參考文獻
1. Annul report,2000.Research, Testing and Training Centre, Gujarat Agricultural university, Junagadh Campus, Gujarat
2. Brown and Schertz, 1967. Principles and practices for harvesting and handling of fruits and nuts, vol.
3. Data book(1992-99). Director of Horticulture, Gujarat state,Ahmedabad. Bulletin No. 20/2000p. 8.
4. Devnani,R.S.1980. Harvesting equipments developed in India. Technical bulletin No. CLAE/78/8, CLAE, Bhopal.
5. Sapovadia B. D., Patel H.N.,Gupta R. A.and Pund S.K.,2001. Design and development of mango harvesting device.AMA 30(1):31-34.
Development and Testing of a Tractor-mounted Positioner for Mango Harvesting
R.A. Gupta，R.M. Satasiya
Pramod Mohnot ，N.K. Gontia
Abstract
In order to reduce losses sustained during harvesting of mango and to maintain fruit quality, a tractor- mounted positioner was developed and tested for mango harvesting at the Sagadividi farm of the Gujarat Agricultural University, Junagadh Campus. During operation, it was observed that using the positioner for harvesting, only the mature fruits with stalk of 10-20 mm length with out sap bums and any other damage to the fruits, could be harvested. White layer (bloom), which is desir able from quality point of view, was also maintained. Though the work output was slightly reduced over all economics was in favour of the use of the positioner for harvesting as compared to the traditional picker. Using a positioner in orchards can save about Rs. 1,000 per tree in a good season.
Introduction
Mango (Manaifera indica),、the “king” of fruits, has prime impor tance among the commercial fruits grown in India-the largest producer and exporter of mango in the world. In Gujarat about 382 thousand tonnes of mango is produced annu ally over an area of 57 thousand hectare (Data book 2000). Gujarat produces export quality of mango mainly the Alphonso and Kesar va rieties. The latter has excellent quality for export and grown almost throughout the state, concentrating in South Gujarat and Saurashtra. The quality of the fruits mainly de pends on their maturity stages , har vest and post harvest techniques adopted by the mango growers.
Harvesting of fruits in India is mostly done manually by means of a curved knife, pair of scissors or blades attached to a hanging basket to the distal end of bamboo sticks (Devnani, 1980). For harvesting mango, hand picking manually op erated low capacity gadgets and tree shaking methods prevaile which re sults in high labour and energy re quirements, drudgery, damaged fruits, damage to tree branches etc. The damage and bruising are very serious problem. The fruits should not be allowed to fall on the ground as the injured fruits cause spoilage to other healthy fruits during pack aging and storage. Fruits harvested with 8-10 mm long stalks appear better on ripening as undesired spots on the skin caused by sap bum are prevented. Such fruits are less prone to stem — end and rot and other stor age diseases (Sapovadia et. al. 2001).
RTTC, Jurhat, Assam (1988) worked on fruit harvesting devic es. The manually operated unit worked on the principle of individ ual fruit cutting by sickle / blade and collecting the fruit in a bag. The unit was found suitable for av erage size and big fruits, which would be damaged if allowed to fall freely on the ground. The other unit worked on the principle of me chanical shaking of tree. This unit was suitable for hard fruits. Brown and Schertz (1967) also worked on mechanically operated harvesters and reported that fruits harvested by mechanical shaking have more in juries in the form of splits, internal and external bruising and superfi cial peel scars than manually har vested fruits.
RTTC, Gujarat Agricultural Uni versity, developed an improved picker and it showed better perfor mance as compared to other pickers collected from various centres of the country. About 90% of the fruits could be harvested with stalk of 10-20 mm in length, which is most desirable specifically for ex port quality of fruit. Fruits should be harvested manually using me chanical aids like a positioner on which a person can stand and pick the fruit using a pair of scissors / secateure. As the fruits are picked form very close distance hence, only mature fruits are harvested without any damage. Hence, keep ing the foregoings in view, a study for developing and testing of a trac- tor-driven and hydraulically operat ed positioner was undertaken at the centre.
Material and Methods
Prior to the design of the ma chine some preliminary informa tion regarding the tree characteristics were studied to en sure that the movability of the ma chine in the field, distribution of fruits within the tree and the per centage of fruits that can be har vested are estimated (Tables 1 to 3). The height of the machine and size of the cage were likewise studied. Using the above information a hy- draulically-operated positioner for harvesting mango and other fruits, was designed and developed. The safety factors were also taken into consideration. The cost of the ma chine was kept minimum by reduc ing the number of moving components in the design of the machine.
The machine consists of a frame, three-point linkage, hydraulic jack, supporting links,, extension pipe and cage. The frame of the ma chine is fabricated from angle iron of (50 × 50 × 6) mm size. The di mensions and structural members of the frame are shown in the Fig. 1. A hydraulic jack of 2 tonnes ca pacity with two cylinders is mount ed at the centre of the frame with the help of a pin of 40 mm passing through two plates welded to the frame and lower end of the hydrau lic jack. The upper end of the jack is supported by fastening three sup ports to the frame and upper end of the jack. Similarly, the upper end of the piston is fastened to a flange through nuts and bolts. To extend the height of the positioner an ex tension pipe of 100 mm and 1 m length is attached to the upper end of the piston through flange, nuts and bolts. On the upper end of the extension pipe another flange of the same size (20 × 20) cm is welded on which cage is fixed through nuts and bolts. The cage of machine is fabricated from angle iron, mild steel flat and wood. The frame of the cage is made out of angle iron. The size of the cage is (92 × 76 × 70) cm. At the bottom of the cage, wooden plank is provided. On one side of the bottom an opening of (55 × 47) cm size is provided through which an operator can get on the positioner to pick up the ma ture fruits. All the four sides of the positioner are kept folding so that when the machine is on transport from one place to another the sides can be lowered to keep the height minimum.
To operate the machine, it is hitched to a tractor through three point linkages and hosepipe of the hydraulic jack is connected to the hydraulic system of the tractor. The cage is mounted on top of the ex- tens4?n piece and its sides are fold ed. The machine is transported to the orchard where mango picking is to be done. During operation, the machine is placed on ground and operator gets on the cage along with a pair of scissor and carton through the opening provided at the bottom of the cage. All the sides of the cage are kept in upright position and hinged to the frame through hooks pins for safety point of view. The hydraulic system of the tractor is operated to lift the cage. As soon as the valve is opened, the oil under pressure goes to jack through hosepipe, which lifts the piston of the jack, thus, the cage is lifted. When required height is reached, valve is closed to stop further upward movement of the cage. Then, the operator pick the fruits from a very close distance using a pair of scissors / secateure. Only matured fruits are picked and kept in the carton.When the carton is full of fruits it is packed and taken on the ground. The machine is taken around the tree to pickup matured fruits. Some of the fruitswhich are located on the top of the tree, are beyond the reach of the operator, are picked using manually operated mango picker.
Fig. 1 Tractor-mounted positioner for harvesting mango.
Fig. 2 Positioner attached with power
Fig. 3 Operator picking mango using positioner.
Testing
A field testing of the machine was conducted at the Sagdividi farm of Gujarat Agricultural University, Junagadh campus for the Kesar variety of mango which is very popular among in the Saurashtra region of Gujarat state. The
trees were planted at (12 X 12)m distance. HMT zetor tractor of 35 hp was used to operate the machine. An experienced worker was engaged to pick the fruits in standing posture on the positioner. During testing of the machine some important observations like number of fruits harvested / h, weight of fruit harvested / h, average stem length (mm), visible damage (%), physiological loss of weight (%),
shelf life of fruits (days) etc. were recorded.
The cost of harvesting was determined out considering the prevailing rates of the tractor and labour during the season. Two workers,one for picking the fruits and another to receive the harvested fruits,were required for the operation.The experienced worker is engaged in picking the fruits and was paid better than the less experienced worker. The same workers were used to harvest the fruits using the developed machine.
In order to estimate physiological loss in weight (PLW) of the har vested fruits two plastic trays lined with newspapers, were kept on the table at room temperature (20°) and the harvested fruits were arranged in these trays in line keeping the stem end upward. The weight of the fruits was recorded every three days. On the 7th day, few fruits har vested using traditional picker showed symptoms of deterioration， are removed from the tray.
Fig. 4 Fruit packet being taken from the positioner.
Fig. 5 Operator picking coconut using positione
Fig. 6 Fruits harvested using traditional mango picker.
Fig. 7 Fruits harvested using developed positioner.
Results and Discussion
(i) Harvesting capacity
The results recorded during the trial of the machine are shown in Table 4. The average number of fruits harvested using the positioner were 360 per hour compared with local mango picker which can pick an average of 377 fruits per hour. Thus, using the positioner the har vesting capacity of the operator was slightly reduced. Considering that in raising / lowering and shifting the positioner took more time. Similar results were reported by Schertz (1967). During his study he observed that an operator stand ing on the ground was more effi cient than harvesting the fruits from a ladder / positioner.
(ii) Stem length
The stem length is one of the most desirable parameter’，The stem length of the stem fruits har vested using the positioner was within 20 mm. and uniform while in fruits harvested with traditional picker, had stems more than 50 mm and non-uniform. A number of fruits were harvested without stem, which is not desirable from the quality point of view. Such fruits do not have good appearance and a mango grower has to sell them at lower prices in the market. More over, it has been reported that fruits harvested without stem are subject to the occurrence of stem end rot disease. Fruits with stems recorded delayed ripening. It is necessary that the fruits should have stems ranging from 10 to 20 mm.
(iii)Visible damage
Visible damage on the fruit was observed in the form of sap burns. The fruits harvested without stem had sap bums. Such type of dam age was almost nil in fruits harvest ed using the positioner because all the fruits had stem while the fruits picked using the traditional picker shows 11.11% visible damage.
(iv)Shelf life of fruits
This refers to the life of fruits in days for which they can be stored after harvesting without sustaining spoilage. The shelf life is affected by the harvesting methods. Fruits harvested using the positioner could be stored for 9 days without show ing symptoms of spoilage. The ap pearance of the fruits was good and had attractive color. In comparison, those harvested using the traditional picker should dark spots on the body on the 7th day from the date of harvesting. If the fruit is physically damaged or injured the respiration rate of the fruit is increased and it is prone to microbial attack hence, during handling of the mango fruit, care taken to avoid any kind of inju ry and increase the shelf life of the fruits.
(v)Cost of harvesting
As indicated in the Table 4 the cost of harvesting for using the po sitioner was Rs. 2783 / tonne of mango fruit as compared to Rs. 368 / tonne using the traditional picker. Thus, the cost of operation for the former was high but the quality of harvested fruit was very good and not a single fruit was lost by way of spoilage or decay while 10 -15%
fruit loss was observed in case of traditional picker. Hence, consider ing 10% loss out of every 1000 kg. only 900 kg. of fruits were avail able for sale. That too at lower rate (Rs. 17.50 / kg') amounting Rs. 15,750. The fruit harvested using the positioner could be sold at high er price (Rs. 20 / kg.) amounting Rs. 20,000, thus gaining Rs. 4,250 more as compared to using the local picker. Subtracting the extra oper ating cost required in the case of the positioner i.e., Rs. 2,415 a net profit of Rs. 1835 / tonne could be har vested by a mango grower. In other words, about Rs. 900 / tree can be saved by adopting the developed positioner for harvesting of mango.
(vi) Physiological loss in weight
Observations regarding the phys iological loss in weight (PLW) were also recorded every three days in the laboratory for each method of fruit harvesting in percentage and presented in Table 5. The PLW was higher on 3rd, 6th and 9th day for the fruits picked using the traditional mango picker. The total PLW was 13.27% and 15.88% for fruit har vested with the positioner and tradi tional picker, respectively.
Fig. 8 Tractor mounted positioner.
Conclusions
From the study following conclu sions can be drawn:
Using the positioner, mangoes without any mechanical injury are picked and only matured fruits are harvested as operation is conducted at a close distance.
As 100 percent fruits are harvest ed with stems (1-2 cm), no sap bums were found and white layer (bloom) on the fruit is also main tained.
Loss of fruit during storage and transportation is minimized.
Due to high quality of fruit main tained during harvesting an fruit grower can harvest a net sum of Rs. 1000 per tree in a good season.
REFERENCES
Annual report, 2000. Research, Testing and Training Centre, Gujarat Agricultural university, Junagadh Campus, Gujarat.
Brown and Schertz, 1967. Princi ples and practices for harvesting and handling of fruits and nuts, vol.
Data book (1992-99). Director of Horticulture, Gujarat State, Ahmedabad. Bulletin No. 20 / 2000 p. 8.
Devnani, R.S. 1980. Harvesting equipments developed in India. Technical bulletin No. CIAE / 78 / 8，CIAE, Bhopal
SapovadiaB.D., Patel H.N., Gupta R.A. and Pund S.K., 2001. Design and development of mango harvesting device. AMA30(l): 31-34.