2018 5th International Conference on Electric Vehicular Technology (ICEVT) October 30-31, 2018, Surakarta, Indonesia 978-1-5386-9164-9/18/$31.00 ©2018 IEEE 167 Development of Low-Cost Autonomous Emergency Braking System (AEBS) for an Electric Car Mochammad Ariyanto Department of Mechanical Engineering Diponegoro University Semarang, Indonesia ari_janto5@yahoo.co.id Gunawan D. Haryadi Department of Mechanical Engineering Diponegoro University Semarang, Indonesia gunawan_dh@yahoo.com M. Munadi Department of Mechanical Engineering Diponegoro University Semarang, Indonesia muna_096@yahoo.com Rifky Ismail Department of Mechanical Engineering Diponegoro University Semarang, Indonesia ismail.rifky@gmail.com Zulfa Hendra Department of Mechanical Engineering Diponegoro University Semarang, Indonesia hendra.zulfa@gmail.com Abstract—This paper presents the development of a low-cost Autonomous Emergency Braking System (AEBS) that can assist the driver or take over the electric car prototype for slowing down and breaking the car at the low-speed condition. An Actuator of AEBS is selected from DC motor that widely found on the market. The proposed AEBS is placed under the hood of the car. The AEBS will pull the brake pedal by using a Bowden cable. Ultrasonic sensor will be used for measuring the distance between the electric car and obstacle. On-off control will be developed for controlling the AEBS in breaking the electric car when the obstacle is approaching. After the AEBS prototype has been built, it will be employed in the electric car and tested for the automatic braking system. Based on the test results, the proposed AEBS can slow down and brake the car before colliding with the obstacle. The AEBS system will be activated when the distance between the car and the obstacle is less than 3.6 m. Based on the test result, AEBS can slow down and brake the electric car before colliding with the obstacle. Keywords—low-cost, electric car, AEBS, braking system I. INTRODUCTION One of the most common causes of accidents in the road is when a vehicle driver does not focus in driving the car like using a cell phone, tired body condition, having many thoughts and others while the vehicle in front of the car braking suddenly. The driver does not have time to brake or slow down the vehicle so that the vehicle will collide the car in front of him/her. To reduce the number of vehicle accidents due to these factors, it is important to develop the automatic control system that can make braking or slowdown of the car/vehicle when the driver is not in the ready state [1], [2]. The Autonomous Emergency Braking System (AEBS) is an automatic braking technology that combines sensors and brake controls to prevent collisions. Some automatic braking systems can prevent collisions at all, but most are designed to reduce vehicle speed before crashing into the front of the car. Because high-speed accidents are more likely to be fatal than low-speed collisions, automatic braking systems can save lives and reduce the amount of property damage that occurs during a crash. Some of these systems provide braking assistance to the driver, and the others can activate the emergency braking without input from the driver. Some researchers use various sensors to measure the obstacle in front of the car. Laser scanner sensor has been used to measure the distance by research study [3]. The research shows that the laser scanner sensor can measure the distance needed for braking and slowing down the vehicle. Junkwang Kim [4] developed the Autonomous Emergency Braking (AEB) System based on commercial radar. The AEB can successfully work with the long braking distance from 3.3 m to 31.7 m. Radar has been widely used in AEB research study [5]–[7]. Another widely used AEB sensor in the commercial car is LIDAR [8]. The AEBS based LIDAR has successfully reacted to emerging objects in time. In this study, we proposed a low-cost braking system called Autonomous Emergency Braking System (AEBS). The AEBS will take over the car when the human driver is not ready to brake the car. This active braking safety system is usually installed on luxury cars. In this study, the developed AEBS uses the ultrasonic sensor for measuring the distance between the electric car and the obstacle, as well as DC motor as an actuator which will pull the brake pedal. Before the automatic braking work, the system will give a warning stage of alarm sounds and displays on the LCD. For controlling of AEBS, modified on-off control will be employed in this research. The proposed AEBS will be implemented on the prototype of an electric car for autonomous braking at the low- speed test. II. DESIGN OF AUTONOMOUS EMERGENCY BRAKING SYSTEM (AEBS) In the development of Autonomous Emergency Braking System (AEBS), the first thing to do is to model a brake pedal pulling mechanism that can move the brake pedal when the driver does not respond. This mechanism is attached to the brake pedal lever which will be connected via Bowden cable and pulled by with a high torque DC motor. Power window DC motors are usually used to drive the car window with a large torque of ± 30 30kgf.cm and a gearbox inside it. Power window motors are also very easy to get, and the price is not too expensive. Based on these considerations, it was decided to become the actuator in the proposed AEBS. TABLE I summarize the specification of the selected power window motor. Gear is chosen to transmit power from the motor to the shaft which will rotate the roller to pull the brake pedal. The manufacturing is also not too difficult. In addition to continuing power, the gear can also increase torque by increasing the number of teeth. In the power window, the