This report is a documentation of my work as a part of my internship at Nissan Ashok Leyland Technologies Ltd. The work initially involved the study and analysis of Real World Driving Cycles to decide on the parameters to be considered for the development of a half an hour drive duty cycle. This duty cycle is used for testing various vehicle parameters on the Chassis Dynamometer. The duty cycle duration is typically limited to reduce per-vehicle test costs. The various parameters that affect the resulting condensed cycle are considered based on various studies in the preparation of a condensed cycle. The original full cycle and the condensed cycle are then run in “Cruise” software and the results are compared. It was observed that the similarity in the results between the on road cycle and the condensed cycle was proportional to the similarity in the individual parameters for both the cycles.
The on road velocity profile is taken as the input for the MATLAB code. Parameters like acceleration and rate of acceleration were found out. Reference values were set for velocity and acceleration to distinguish accelerating, decelerating, idling and cruising intervals. The interval (profile) between two consecutive idling periods was identified as a micro-trip. The condensed cycle was created by combining selected micro trips. Originally in the excel sheet which was developed for the same purpose of creating a condensed cycle similar procedure was followed. But the main disadvantage of doing in Excel is that the selection of micro trips had to be done manually and the percentage error between the original and condensed cycles used to be high. These problems were given consideration. Also additional parameters were included for the selection criteria. By using the code it was ensured that all the combinations of micro trips were considered and the percentage error in the parameters for each of them was calculated, so that the best combination is derived with the desired specifications. This is the summary of the project.
The on road velocity profile is taken as the input for the MATLAB code. Parameters like acceleration and rate of acceleration were found out. Reference values were set for velocity and acceleration to distinguish accelerating, decelerating, idling and cruising intervals. The points where the shift takes place between these were determined. The percentage of occurrence of each type of shift was calculated and noted for the full cycle and also for the micro trips. Also the percentage time and distance of these 4 intervals was calculated for the full cycle and the micro trips. The maximum and minimum values of speed, positive and negative accelerations in the complete duty cycle were noted. The same was done for all the individual micro trips.
A code was written such that certain number of micro trips will be combined to form a condensed duty cycle. The logic was written such that all the combinations of micro trips will be considered and...