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Towards the effort of reducing pollutant emissions, especially soot and nitrogen oxides, from direct injection Diesel engines, engineers have proposed various solutions, one of which is the use of a gaseous fuel as a partial supplement for liquid Diesel fuel. These engines are known as dual fuel combustion engines. A dual fuel (Diesel-CNG) engine is a base diesel engine fitted with a dual fuel conversion kit to enable use of clean burning alternative fuel like compressed natural gas. In this engine diesel and natural gas are burned simultaneously. Natural gas is fed into the cylinder along with intake air; the amount of diesel injection is reduced accordingly. Dual fuel engines have number of potential advantages like fuel flexibility, higher compression ratio, and better efficiency and less modifications on existing diesel engines. It is an ecological friendly technology due to lower PM and smoke emissions and retains the efficiency of diesel combustion.

Vehicle localization and position determination is a major factor for the operation of Autonomous Vehicle. Errors or unavailability of resources to determine this, poses a serious threat not only to the vehicle but also the environment around it. Global Positioning System (GPS) is one of the most common resources to determine position about the reference geographic coordinate system. But this resource has several drawbacks of its own viz. clock errors, multi-path errors and also uncertainty of good signal strength due to weather conditions or physical barriers. Also an additional drawback of a low-update rate makes it unreliable for the Autonomous Localization algorithm to operate on this. Thus a system is required which has no external environment dependencies to determine the position of the vehicle. Inertial Measurement Unit is a coupled system comprising of a 3-axis accelerometer and 3-axis gyroscope which records body force accelerations and the yaw rate.

On-board diagnostics (OBD) is a term referring to a vehicle's self-diagnostic and reporting capability. It is a system originally designed to reduce emissions by monitoring the performance of major emission related components. There are two kinds of on-board diagnostic systems: OBD-I and OBD-II. In India OBD I was implemented from April 2010 for BS IV vehicles. OBD II was implemented from April 2013 for BS IV vehicles. Apart from the comprehensive component monitors, OBD II system also has noncontinuous monitors like Catalyst monitoring, Lambda monitoring, and other after treatment system monitors. For OBD II verification and Validation, it is required to test all the sensors and actuators that are present in the engine, for all possible failures. From an emissions point of view there are lists of critical failures that are caused due to malfunction of sensors and actuators. Carrying out the full matrix failure testing on the running engine could be tedious, unsafe and time consuming.