Rancang Bangun Konverter Biogas untuk Motor Bensin Silinder Tunggal

The need for energy continues to increase along with the increase of population in Indonesia. This is in contrast with the fact that the main oil energy source is reducing day by. To overcome this problem renewableenergy sources such as biogas becomes very important. Methane content in the biogas ranged between 60-65 %, where the value is large enough to be used as an energy source replacement of gasoline. The purpose of this study is to design a converter that is capable to perform biogas and air mixing for optimum use of biogas in gasoline engine. The main parts of biogas converter are the venturi, choke valves , throttle valves, as well as the coupler to the engine. Testing was done by applying converter on a gasoline engine with biogas fuel. Engine performance was tested using a dynamometer and the results are compared with the performance of the motor using gasoline fuel. Test results show that the optimal power is achieved at 0979 kW at 3146 rpm and a torque of 4.3 Nm, while the motor power with gasoline kW and a torque of 1.86 Nm at 6:21

Pengembangan Metoda Deteksi Rintangan untuk Traktor tanpa Awak Menggunakan Kamera CCD

For unmanned tractor guided by global positioning system, ability for eluding obstacles such as trees, big stone, cavity, bund, people, and other objects in the work area is very important in order not to stop the operation.Surrounding detection system using CCD camera makes it possible for unmanned tractor to detect obstacles in front of it realtime. However, with so many different objects that may captured by the camera, it will need a lot of image processing steps that takes a lot of time so it is no longer suitable for realtime detection in application. The proposed research is aimed to develop a simpler obstacle detection method by adding a red laser pointer to the CCD camera used to capture scene in front of the tractor. The red laser light that reflected by an obstacle gives an important information in the image, and the distance of the obstacle could be calculated based on phytagoras theory. The results showed that all obstacles with 1 m distance, 80% obstacles with 2 m distance, and 40% obstacles with 3 m distance could be detected. Obstacles with more than 3 m distances could not be detected due to weak laser light for the distances. The accuracy of distance prediction for all situation is 67.5%, which is still need improvements

Desain dan Pengujian Mesin Sortasi Telur Ayam

Based on Indonesian National Standard (SNI) No 3926:2008, egg weight is classified into three classifications: small (<50 g), medium (50-60 g), and large (>60 g). Nowadays egg grading process in Indonesia was still done manually. The objective of this research was for designing, constructing, and performance testing of egg sorting machine. The machine testing includes performance accuracy, machine capacity, and egg crack of the sorting result. The egg sorting machine consisted of five main parts: conveyor system, steering conveyor system, sorting conveyor system, and exit conveyor system. Test result showed that the machine could sort the egg with accuracy of 83 % without any cracking in eggshell. The machine capacity was most affected by the speed of sorting conveyor system. The variables which influence the speed of sorting conveyor system were initial speed rotation (Na), work speed rotation (Nb), and length of the track on initial speed rotation path (L). The maximum machine capacity was 61 eggs per minute and obtained by configuration of Na, Nb, and L of 15.5 rpm, 24.5 rpm, and 6 cm respectively

Karakteristik Fisik dan Mekanik Kemiri (Aleurites Moluccana Wild.)

It is very important to know the characteristics of candle nut before designing nut-deshelling machine. This study was conducted to investigate physical and mechanical characteristics of candle nut before analyzing the impact force on the de-shelling process. The result showed that average diameter of candle nut at intercept A (length), B (width) and C (thickness) were 32.55 mm, 29.05 mm and 23.23 mm respectively. The average value of sphericity and roundness of candle nut were 0.86 and 0.65 respectively. At high moisturecontent candle nut had a greater value of compressive strength and resulted a sticky kernel in the shell. Candle nut had 4.96% db moisture content after dried at sun drying for 20 hours. The value of compressive strength from the maximum load during a compression test (rupture force) of candle nut at this moisture content were 1,208 N, 1,198 N and 1,950 N for intercept A, B and C respectively

Analisis Gaya Spesifik Pemotongan Sabut Kelapa Muda (Cocos Nucifera)

To design a young coconut trimming machine, it's important to analyze the cutting mechanism of young coconut husk. The aim of this study were to analyze the cutting mechanism of young coconut husk and generate mathematical model of specific cutting force. Sharpening angle, cutting angle and sharpened knife were optimized to get the lowest cutting force. Mathematical model has been generated to estimate the maximum cutting force for one side sharpened knife and two side sharpened knife with cutting angle (θ) at 0Oand above 0O. Based on the analysis of this study, the type of knife that require the lowest cutting force is two side sharpened knife with sharpening angle (β) = 10O and cutting angle (θ)= 30O

Desain Konseptual Penangkap Tandan Buah Sawit dan Pemanfaatan Energi Potensialnya

In oil palm harvesting, falling fruit bunches have a considerable potential energy, which can be captured and used to power the wheelbarrow in evacuating the fruit bunches. This study was conducted to measurethe engineering characteristics of fruit bunches harvesting, determine the best fruit bunches catchment platform material, analyze the potential energy of falling fresh fruit bunch, and design a conceptual designof the catchment platform and evacuation machine. Measurements of the characteristics of the harvesting were done in an oil palm plantation. Four types of fruit catchment platform materials were tested, namely:steel plate, wood board, expanded steel plate and rubber sheet. The results showed that, bunches fell at a distance between 0.6 m to 1.4 m from the tree. Fruit bunches weight was in the range of 16 kg to 32 kg.The rubber catchment platform was superior to the other materials in reducing the scattered loose fruits and bruised fruits. Potential energy of falling fruit bunches were in the range of 0.44-4.44 kJ. Theoreticaltraveling distance of the wheel barrow powered by the captured potential energy was in the range of 2.27 m - 22.98 m. Based on the data obtained, a conceptual design of catchment platform and evacuation machinewas designed

Desain Roda Besi Bersirip Traktor Dua-roda dengan Bantuan (Cad).

Traction performance of a cage wheel for two-wheel tractor depends on its shape dimension, lugs materials and soil condition. In order to get the optimum design of the cage wheel, the relation betwen tractor, implement and soil condition should be considered carefully. The objective of this research was to determine optimum design parameter of cage wheel based on working condition of tractor and to make a computer program for design analysis and for producing engineering drawing of the cage wheels. Soil condition and two-wheel tractor construction were measured and the data was used for getting the optimum design parameters by using optimization method. A computer program was developed and employed for the optimization process and for drawing the design result. As a trial of the program, the optimum design parameters of cage wheel for Yanmar YST-EX tractor working at Sawah Baru rice field were found to be: 80 cm of wheel diameter: 10 lugs: 19.63 cm x 9.68 c, of lug size; and 20o of lug angle. The result revealed that the program could determine the optimum design parameters and could produce the engineering drawing of the cage wheel property

Metode Pembuatan Guludan secara Mekanis DenganTenaga Penggerak Traktor Dua Roda untuk Budidaya Tanaman Sayuran

The objective of this study was to determine the best tillage method for making planting beds forvegetables cultivation using a two-wheel type tractor. Five tillage methods using a two-wheel type tractorwith its equipments were tested and evaluated in this study. The methods which were tested were: 1)plowing using a reversible type plow, followed by ridging using a ridger and finished by harrowing using arotary tiller (B-F-G 1 method) ; 2) plowing, followed by harrowing and finished by ridging (B-G-F method);3) plowing, followed by harrowing followed by ridging and finished by 2nd harrowing (B-G-F-G method); 4)plowing, followed by 40 cm width of harrowing and finished by ridging (B-G-F 2 method); and 5) plowing,followed by 40 cm width of harrowing and finished by ridging with 40 cm tractor wheel-base (B-G-F 3method). The experiments were conducted on several plots of dry land. The results of the experimentsshowed that the B-G-F 3 method produced the best planting bed form, an appropriate bed size and abetter soil condition for vegetables cultivation. The field capacity of this method was 74 m2/hour and wasthe highest capacity among the five methods