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Range of an electric vehicle is one of the most prominent decisive factors for a person willing to buy an electric vehicle. In this paper an algorithm is developed to estimate the load carried by the truck or passengers in case of a bus and accordingly switch between ECO, ECO+, Normal, Power, and Power+ modes. This is similar to the ECO/Power switches available in the vehicles, but here auto switching is done to reduce driver dependability and allow vehicle to operate in 5 different modes without driver intervention. Optimum utilization of available torque is done for efficient operation of the vehicle in all load and road conditions. The model-based software development using MATLAB Simulink is used to develop an algorithm which will switch to Power or Power+ torque mode if the vehicle is fully laden or if the vehicle is going on a steep hill, whereas the algorithm will switch to ECO+ or ECO mode if the vehicle is empty or carrying less load.

In today’s automobile industry refined NVH performance is a key feature and of high importance governing occupant comfort and overall quality impression of vehicle. In this paper interior noise and vibration measurement is done on one of the light truck and few dominant low frequency noise booms were observed in operation range. Modal analysis was done for the cabin at virtual as well as experimental level and few modes were found close to these noise booms. Vibrations were measured across the cabin mounts and it was found that the isolation of front mounts is not effective at lower frequencies. Taking this as an input, the mount design was modified to shift the natural frequency and hence improve the isolation behavior at the lowest dominant frequency. This was followed by static and dynamic measurement of the mounts at test rig level to characterize the dynamic performance and stiffness conclusion.

Wheel end bearing is one of the critical components of the vehicle as it shares the loads & support wheel rotation simultaneously. In wheel end, taper roller bearings are used. It helps to withstand both vertical & lateral loads imparted during cornering. Taper roller bearings are used in pair of two so that overall impact of lateral forces during straight running would be nullified. In wheel end bearing systems bearings are kept at distance w.r.t to each other based on position of load line, sharing the total portion of load accordingly. Life of bearings is dependent on whether the bearings are operating in play or preload. This paper focuses on various aspects of bearings life & how it varies with respect to Play & Preload. Also a methodology is developed to measure the overall preload of bearing system. In second stage a methodology is developed which gives an indirect method to measure the bearing preload in terms of wheel end torque to rotate.

Ride Comfort forms a core design aspect for suspension and is to be considered as primary requirement for vehicle performance in terms of drivability and uptime of passenger. Maintaining a balance between ride comfort and handling poses a major challenge to finalize the suspension specifications. The objective of this project it to perform ride- comfort analysis for a commercial truck using MATLAB Simulink. First, benchmarking was carried out on a 4x2 commercial truck and the physical parameters were obtained. Further, a mathematical model is developed using MATLAB Simulink R2015a and acceleration- time data is collected. An experimentation was carried out on the truck at speeds of 20 kmph, 30 kmph, 40 kmph and 50 kmph over a single hump to obtain actual acceleration time domain data. The model is then correlated with actual test over a single hump. This is followed by running the vehicle on Class A, B & C road profiles to account for random vibrations.

In the modern era of commercial vehicle industry, passenger and driver comfort is one of the major parameters that improves vehicle running time which leads to fleet owner’s profitability. Air conditioning system is one such system whose primary function is to provide the required cooling inside the cabin in hot weather conditions. An Air-conditioned truck cabin creates a comfortable environment for the driver which increases his efficiency and reduces fatigue. An AC compressor consumes power directly from the engine affecting fuel economy and vehicle performance. With ever increasing demand for energy efficient systems and thermal comfort in automobiles, AC systems should be able to deliver the required cooling performance with minimum power consumption. Therefore, reducing AC power consumption in vehicles is one of the key challenges faced by climate control engineers.

The cabin or cab is an enclosed space where the driver and co-driver are seated. Structural parameters such as modal and stiffness characteristics are of key importance for its durability study and driver’s comfort. The desired strength and stiffness value of the cabin have to be met at the development phase itself. In developing new cabin models numerical simulations are used for estimating vehicle performance to reduce the development cycle. But, the conventional method of modeling the cabin using 2-d elements and performing subsequent iteration steps to arrive at the desired stiffness and strength value will be cumbersome and time consuming. Thus, a methodology of FE modeling of the truck cabin using 1-D elements has been proposed in this paper which will reduce the analysis time of successive iterations. For this purpose an existing proven driver’s cabin is modeled using 1-D elements.

The main emphasis for a commercial vehicle design which was focused on fuel-economy and durability does not fulfill the increasing customer expectations anymore. Commercial vehicle designers need to focus on other vehicle aspects such as steering, ride comfort, NVH, braking, ergonomics and aesthetics in order to provide car like perception to truck, bus drivers and passengers during long distance drives. Powertrain mounting system must perform many functions. First and foremost, the mounting system must maintain & control the overall motion of the powertrain, to restrict its envelope reasonably, thereby avoiding damage to any vehicle component from the potential impact. This requires the mount to be stiff. Second the mount must provide good vibration isolation to have a comfortable ride to the vehicle occupant. This requires the mount to be soft.