Utveckling av fordonsprototyp för analys av låghastighetskörning

Abstract

This thesis presents the design and development of a vehicle prototype with an integrated measurement system for analyzing speed, acceleration and jerk at low velocities. The purpose of the project was to create a low-cost platform that can be used to study vehicle dynamics at low speeds, with focus on measuring jerk during acceleration from standstill and braking. The prototype was powered by a 12 V DC motor, with power transmitted to the rear wheels through a belt drive. Braking was achieved using a bicycle brake system controlled by a servo motor. The measurement system was based on an Arduino UNO Q, which was used as the control unit. Hall sensors were used to measure speed, while an MPU-6050 accelerometer was used to measure acceleration. To improve the reliability of the acceleration values, sensor fusion was used by combining data from the hall sensor and the accelerometer. The acceleration value was weighted with 70% from the hall sensor and 30% from the accelerometer. Wireless control and data collection were done using an HM-10 Bluetooth Low Energy module and a web application developed in HTML5 and JavaScript. Two test runs were conducted, and the results showed that jerk was highest during braking and acceleration from standstill, with a maximum value of 4.83 m/s³ measured during braking. Overall, the system shows that cost-effective hardware can be used to study vehicle dynamics at low velocities and provides a foundation for further development with different loads, speeds and road surfaces.