COMPARING THE ACCELERATION CAPABILITY AND POWER TRANSMISSION OF A 4-SPEED AUTOMATIC TRANSMISSION AND A CVT TRANSMISSION IN A TOYOTA VIOS USING DYNAMIC SIMULATION

Abstract

 This study presents a comparative analysis of the acceleration capability and power transmission characteristics of two transmission configurations—a 4-speed automatic transmission (4AT) and a continuously variable transmission (CVT)—equipped on the 2015 and 2016 Toyota Vios. With the same engine platform and specifications, longitudinal dynamic simulation was performed using CarSim software to evaluate the impact of each transmission type on speed, longitudinal acceleration, wheel torque, and longitudinal traction force. The results show that the CVT maintains continuous power transmission and provides better acceleration in the low to medium speed range thanks to its smooth variable transmission ratio and ability to keep the engine operating near its optimal torque range. Conversely, the 4AT generates greater initial wheel torque but experiences torque and acceleration drops during gear shifts, reducing acceleration performance. At high speeds, the difference between the two configurations diminishes due to the predominant influence of aerodynamic drag. The research results confirm the CVT's advantage in terms of continuous power transmission and acceleration efficiency, while also demonstrating the effectiveness of CarSim in simulating and evaluating the drivetrain characteristics of small passenger cars.