Embedded System Using Field Programmable Gate Array (FPGA) myRIO and LabVIEW Programming to Obtain Data Patern Emission of Car Engine Combustion Categories

Engine scanner unit is a tool used by mechanical power to know the condition of car engine combustion at the time of tune up process done. The level of elements and compounds that dominant in determining categories of combustion of gasoline fuel car engines through the levels of elements and compounds contained in exhaust emissions are Hydrocarbons (HC), Carbon Monoxide (CO), Carbon Dioxide (CO2) and Oxygen (O2). Complete combustion category produces maximum power, fuel efficiency and emission levels according to the threshold. This occurs when there is a balance of the amount of fuel, airflow and ignition in the engine combustion chamber. Elements and compounds contained in car exhaust emissions can be detected with sensors that are sensitive to elemental levels and these compounds are HC, CO, CO2, and O2 sensors. This study aims to display the data pattern category of combustion engine through exhaust emissions based on multi sensor detection processed with signal processing system in the form of Fast Fourier Transform (FFT) process. Furthermore, data pattern is performed in accordance with the category of combustion engine detected. The system is designed with embedded system using Field Programable Gate Array (FPGA) myRIO and LabVIEW programming. The results in the test displays the data pattern and the comparison test of the reference data pattern with the data pattern of the detection result. The comparison test result of data pattern similar to 87% complete engine combustion category and similar to incomplete combustion category 90%. Keywords— embedded system, exhaust gas emission, multi sensor, data pattern.


I. INTRODUCTION
One of the routine activities undertaken by vehicle owners is to perform service periodically, so that the vehicle engine performance is always in optimum condition with efficient fuel consumption. Service activities that are often done is tune up the engine combustion. The objective is to obtain maximum fuel efficiency and maximum engine power with exhaust emission conditions which is in accordance with permissible threshold standards often referred to as the category of complete combustion. While the incomplete combustion category is the opposite, it is an undesirable condition such as wasteful fuel, less power and exhaust emissions are not up to standard. To detect and process the setting of the engine combustion engine components of the injection system during a tune-up of engine combustion by a technician carried out by means of an engine scanner unit. This tool comes with an engine burning category indicator that is generated to make it easier for technicians to read the results. Unlike the carburetor car system, where the ignition setting, air flow and fuel flow is done mechanically. And for the process of setting it when tune up engine burning by technicians done manually without any definite indicator whether complete or incomplete combustion category has achieved. As a result the technicians have difficulty in obtaining the complete burning category and there are often differences in tune-up results between a technician and other technicians.
Some elements and compounds on emissions gasolinefueled discharges value. The level of elements and gas compounds contained in the exhaust emissions will determine the category of engine combustion. Elements and compounds. that is contained in exhaust emissions play an important role to determine the category of combustion engines are carbon monoxide (CO), carbon dioxide (CO2), hydrocarbon (HC) and oxygen (O2) gases, as shown in compound will be different for the category of complete combustion and incomplete combustion category [2,3]. Complete combustion results can be detected by the level of exhaust emissions based on the reference standard as shown in Table 1. The condition of complete engine combustion is characterized by the occurrence of a balance between fuel, air and ignition in the combustion chamber characterized by the development of elemental and exhaust emission levels. While said to be incomplete combustion in case of imbalance between air, fuel and ignition of fuel room. Due to incomplete combustion is not maximal engine performance, wasteful fuel, high exhaust emissions and noncompliant exhaust emissions standards [2,4].
Engine combustion tune-up are carried out periodically to obtain an efficient fuel consumption with maximum power produced.
Car Injection system tune up performed by a mechanic with the help of detector which is often called the engine scanner unit. This system is able to detect and simultaneously petrify the process of tune up the combustion engine setting fuel, air and ignition of the vehicle to obtain perfect combustion conditions. The engine scanner unit works based on the detection of the sensor data installed on the vehicle exhaust emission channel integrated with the Engine Control Unit (ECU) [5,6].
Unlike carburetor system car, which is not equipped with sensor system and ECU so that the combustion system setting is done mechanically. Table 2 shows the complete combustion category with low HC, low CO, high CO2 and low O2 levels.
The complete engine combustion will also produce exhaust emission levels that conform to the allowed exhaust gas emission limits. For Indonesia, based on the Decree of the Minister of Environment No. 5 of 2005 for motorcycles, gasoline fuel is maximum CO 5.5% and maximum HC 2400 ppm [7].
This study aims to obtain the element content and exhaust emission compounds data patterns form that characterized the category of engine combustion. This process is carried out by detecting levels of elements and exhaust emission compounds that can be detected by using electronic components of gas sensors that are sensitive to elements and compounds of HC, CO, CO2 and O2 gases [8,9,10].  [1,7].

Gas Level
Indicator

II. THE MATERIAL AND METHOD
Excessive exhaust emissions indicate a waste of fuel, resulting in incomplete engine combustion [4]. Electronic fuel injection machine (Electronic Fuel Injection) uses electronic systems to regulate the system of airflow, fuel and ignition automatically resulting in perfect combustion conditions. This is evidenced by lower levels of emissions and environmentally friendly exhaust [12,13].
As for engine fuel system carburettor settings, airflow system and fuel ignition system is set electro mechanically.
To detect the elements and compounds contained in exhaust emissions on engine exhaust emissions of the carburettor system, O2 gas sensor used KE-50, CO2 used MG 811, CO used MQ 7 and HC used TGS 2201 [8,9].
This system is an electronic nose (e-nose) consisting of compound sensors and integrated signal processing in an embedded system and a PC or laptop computer as a display system.
The design of the system made in this study consists of a series of sensors and signal conditioners, as well as the process of Fast Fourier Transform (FFT) as well as data normalization.
The design of this system uses hardware Field Programmable Gate Array Logic (FPGA) myRIO, National Instrument [14,15]. The software used for FPGA myRIO programming is data flow programming using LabVIEW, which is supported by the available libraries [14,15].
The signal and signal conditioning components consist of the electronic components shown in FIG. 1. The signal processor consists of reading the analog input data from the sensor by a certain sampling, using the myrio FPGA module from National Instrument as the target. this process is shown in figure 2. The next stage is FFT, this is done to change the analog data detection sensors in time domain into analog data in the frequency domain with a certain magnitude value. This process is shown in Figure 3.  The final stage is the creation of data patterns that will characterize the category of engine combustion. Data pattern obtained from the FFT is done by selecting a unique frequency that can characterize the category of engine combustion. Figure 4 shows the overall form of the program until the desired data pattern is obtained.

III. RESULT AND DISCUSSION
This is an embedded system consist of modules, while the sensor components used are KE 50 for O2, MG 811 for CO2, MQ 7 for CO and TGS 2201 for HC. The test material is carburetor system car fueled gasoline and pertalite.
The testing process begins with a compound sensor response test against two groups of engine combustion conditions. The first group is a car that has not been tuned up and is known in the category of incomplete combustion. The testing process is done by placing a multi-sensor at the end of the exhaust emission channel. Furthermore, change in the value of each sensor is observed. Figure 6 shows the virtual instrument system for multi sensor responses. The next test is a multi-sensor response test of elements and compounds level contained in car exhaust emissions that have been in the tune-up of engine combustion and is known as complete combustion category. Multi-sensor response results are shown in Fig. 8. From the data of multi-sensor response test to 2 conditions that is before and after engine combustion tune up, seen that magnitude value of each sensor relative before tune up is higher and fluctuate. Mean while, after tune up the value of magnitude is lower and stable. Figures 9 and 10 illustrate a multi-sensor response for a Pertalite-fueled and carburetor car with an incomplete and complete combustion category system.  Furthermore, a multi-sensor response test for gasolinefueled cars with an incomplete combustion category system and complete combustion system are performed. Based on the sensor response result in Fig. 12, we get the average value for HC = 3,54, CO= 1,79, CO2=12,92 and O2 = 1,72. Figures 13 and 14 illustrate multi-sensor response for a Pertalite-fueled car with an incomplete combustion category system and complete combustion.  Furthermore, the test is done in displaying emission gas emission data pattern. The testing process carried out on two conditions before the tune-up process of incomplete combustion and after the tune-up process of perfect combustion. Figure 15 shows the detected data pattern Virtual instrument display. The amount of data selected is 8 frequencies of 32 frequencies displayed by FFT process. These frequencies indicate a unique data pattern shape that characterizes the emission and exhaust gas by category of combustion. The test before the tune up is displayed in the form of a graph of the data pattern in figure 16.  Figure 16 is a data pattern of pertalite-fueled car. From the data pattern obtained, it can be seen that there is a decrease in the magnitude of each pattern.
The next test is displaying the data pattern after tune up process of complete combustion engine. Test results are shown in figure 17. To compare the pattern detection results obtained by the system that is made, the comparison of the test results with the emission level test results is done. The emission level test is performed on the same car before and after engine combustion tune-up. The emission level test results are shown in table 3.  table 3 and table 2 as reference data, the emission levels seen before the engine tune-up is an incomplete combustion engine condition. Meanwhile, after the tune up process is done, obtained complete combustion conditions.
Further tests were conducted on several cars with various manufacturing and product years. The number of vehicles tested was 5 units between 1987 and 1995.
Test results aimed to determine the condition of the burning of the vehicle based on the pattern of data used as a reference or reference. Testing is done by comparing the similarity of reference data pattern with data pattern of detection result. The tested vehicles are the one that has not been tuned up or in unknown conditions of combustion engine. Table 4 shows the identification results of vehicle engine combustion categories tested by reference to the data pattern of complete combustion conditions.

Patern To
The next test is the similarity test pattern data detected by system with reference data pattern of certain combustion categories. The tested car is a car that has been known its burning conditions. The test is being done 30 times. Results data are shown in table 5 for complete burning category  similarity tests. From 30 times test, there is similarity of data pattern of complete combustion as much as 25 times or with percentage of success 83,33%.
Similarity test is done to a car which has complete combustion engine as shown in table 6. The system ability showing the similarity of incomplete combustion is 90%  1  Incomplete  2  Incomplete  3  Incomplete  4  Incomplete  5  Incomplete  6  Complete  7  Incomplete  8  Incomplete  9  Complete  10  Incomplete  11  Incomplete  12  Incomplete  13  Incomplete  14  Incomplete  15  Incomplete   16  Incomplete  17  Incomplete  18  Incomplete  19  Incomplete  20  Incomplete  21  Incomplete  22  Incomplete  23  Incomplete  24  Complete  25  Incomplete  26  Incomplete  27  Incomplete  28  Incomplete  29  Incomplete  30 Complete

IV. CONCLUSION
Based on the results of research and data analysis conducted in this study can be summarized as follows: Sensor magnitude value is relatively highly fluctuated before combustion tune-up. Data pattern magnitude of fueledpertalite car is lower that fueled-gasoline car.
There is a difference between both magnitude values of combustion data pattern, which where the complete combustion data pattern is lower than the incomplete ones. The system ability showing similar data pattern of complete combustion is 83,3 % while incomplete combustion is 90%