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Carburettors are widely used for control of Air/fuel mixture in 2/3 wheeler vehicles in India as well as other countries. Carburettor technology has improved over the years to meet stringent emission requirements as well as fuel economy demands of customer. With the introduction of Euro-III regulations in 2006 and proposed BS IV requirements in India, emphasis is laid on the transient control capability of carburettor. A project was undertaken at Ucal Fuel Systems to understand the transient characteristics of carburettor and develop electronic control to achieve programmable control of Air/Fuel ratio on the driving cycle. Several tests were conducted on carburettor flow test bench and on chassis dynamometer to understand the transient control response and develop control strategy. It is observed that the Air/fuel ratio measured at steady speed trials, have a marked influence on the transient Air/Fuel ratio behavior as measured on drive cycles.

Automotive emission regulations in India are becoming stringent day-by-day. With the deterioration of air quality, the new techniques suitable under Indian condition to reduce the emissions from automotive vehicles are becoming extremely important. In India large percentage of the vehicle population is 2-wheeler vehicles using a mechanical control for the air/fuel ratio. A project was undertaken to develop the simple Electronic Control System (ECS) for 4-stroke 2-wheeler vehicles. With the unleaded petrol available in the India, catalytic converters are becoming popular and are used on almost all passenger car vehicles as well as 2-stroke 2-wheeler vehicles. Efficiency of the 3-way catalytic converters is optimum for all the three pollutants provided the Air Fuel (A/F) ratio is maintained at the stoichiometry. It is very difficult to maintain A/F ratio at stoichiometry with the mechanical controls presently used.

This paper describes the engine mapping work carried out on a 2.1 litre carburetted petrol engine.The purpose of this work was to improve upon the emission levels of the engine to meet 1996 emission norms with sufficient margin and to achieve best fuel economy possible. This paper deals with the strategy for the selection of speed load points required for mapping depending on engine operating zones, engine base data collection, methodology followed in engine mapping, variation of engine performance and emissions with respect to air/fuel ratio and spark timing etc. Further the mass emission predictions for different strategies like leaning the air/fuel mixture, retarding the ignition timing etc. are also discussed. Recalibration of the carburettor based on the above findings, its effect on vehicle performance are dealt with.

Chassis dynamometers are required for different types of regulatory tests like emissions, fuel consumption, etc. as well as for different development tests and running-in of vehicles. With the stringent emission regulations, the chassis dynamometers are required to simulate road resistance accurately and consistently to get repeatable results. This paper describes the new concept of chassis dynamometer using two power devices, an eddy current dynamometer for absorption and a DC machine for generation. Both the machines are controlled through a personal computer (PC) with necessary interfaces. It has been possible to simulate the road resistance accurately on different driving cycles. The software developed has all the required modes for operation. The detailed results are presented in the paper.

Autonomous driving is looked upon as solution for future of automotive vehicles. The technology has tremendous possibilities to improve safety, fuel economy, comfort, cost of ownership etc. The project to develop an autonomous controller from scratch was undertaken, with objective to drive under selected test scenarios. The car, modified to drive using this autonomous controller, is able to handle these scenarios. The key scenarios include ability to successfully drive on tracks with well-marked lanes, Follow the route as per selected trip plan file, recognize and follow all traffic road signs, traffic signals en-route, identify other vehicles on the road or pedestrians in the lane and take the appropriate action. The development was carried out using frugal engineering approach. As the Autonomous Vehicle technology is still under development, the standard proven published approaches are not available.