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A new road feel feedback control design of steer-by-wire (SBW) is proposed, which is produce the steering feel of conventional vehicle with equipped electronic power steering (EPS) system, due to SBW system removes mechanical linkages between steering system and front wheels. A dynamic model is established to study the road feel generation and deal with the need of computed rack force of steer system. Based on the analysis of the assisting characteristic and the active damping control strategy of the EPS system, an integrated road feel algorithm is proposed. For rack force is difficult to measure, an estimator is presented to estimate rack force by Kalman filter (KF). The hardware-in-the-loop simulation (HILS) test bench results show that the proposed road feel control design make drivers get road feel information and SBW system can improve the vehicle maneuverability and comfortably.

Conventional power steering systems can be “tailored” to provide light steering efforts for parking and low speed, or high steering efforts for stability and “road feel” at high speed. In either case, the customer's preferred steering efforts are not provided at all times. Compromises are required. The need for a speed-sensitive steering effort system has prompted the introduction of several innovative variable-assist steering systems in the past few years, which are currently used in some European and Japanese vehicles. This paper describes a Ford-patented variable-assist system used on the 1988 Lincoln Continental, the first application of vehicle speed-sensitive steering to an American-designed and manufactured vehicle. The Ford Variable-Assist Power Steering System is a “rotary steering valve” system. It uses a modification of the current rotary valve to provide low steering efforts (low torsion bar twist) at low speed and higher efforts (more twist) as vehicle speed increases.

The electric power steering (EPS) is increasing its number since there are many advantages compared to hydraulic power steering. The EPS saves fuel and eliminates hydraulic fluid. Also, it is more suitable to the cooperation control with the other vehicle components. The EPS is now expanding to the heavier vehicle with the advance in the power electronics. In order to meet customer's needs, such as down-sizing, lower failure rate and lower price, we have developed the new motor control unit (MCU) for the EPS. The motor and the electric control unit (ECU) were integrated for the better installation. We adopted new technologies of redundant 2-drive design for more safe EPS. “2-drive Motor Control technology” which consists of dual winding, two torque sensors and two inverter drive units. In our developed MCU, even if there is a failure in one of the drive unit, the assistance of the EPS can be maintained with the other drive unit.

The objective of this study was to investigate if 3D auditory displays could be used to enhance parking assistance systems (PAS). Objective measurements and estimations of workload were used to assess the benefits of different 3D auditory displays. In today’s cars, PAS normally use a visual display together with simple sound signals to inform drivers of obstacles in close proximity. These systems rely heavily on the visual display, as the sound does not provide information about obstacles' location. This may cause the driver to lose focus on the surroundings and reduce situational awareness. Two user studies (during summer and winter) were conducted to compare three different systems. The baseline system corresponded to a system normally found in today’s cars. The other systems were designed with a 3D auditory display, conveying information of where obstacles were located through sound. A visual display was also available. Both normal parking and parallel parking was conducted.

The radar-based advanced driver assistance systems (ADAS) like autonomous emergency braking (AEB) and forward collision warning (FCW) can reduce accidents, so as to make vehicles, drivers and pedestrians safer. For active safety, automotive millimeter-wave radar is an indispensable role in the automotive environmental sensing system since it can work effectively regardless of the bad weather while the camera fails. One crucial task of the automotive radar is to detect and distinguish some objects close to each other precisely with the increasingly complex of the road condition. Nowadays almost all the automotive radar products work in bidimensional area where just the range and azimuth can be measured. However, sometimes in their field of view it is not easy for them to differentiate some objects, like the car, the manhole covers and the guide board, when they align with each other in vertical direction.

The growing electrical power demands on bus electrical systems, such as the electric door operator, power steering, braking, air conditioning, windshield wipers, seat heating, and the need to improve emissions and fuel economy, are making current 12/24-volt electrical systems inadequate. For buses to continue to meet growing customer needs, electrical power must be increased. The industry is currently pursuing a 42-volt system as standard. In the U.S., that number (42 volts) was selected by an industry-wide research consortium led by the Massachusetts Institute of Technology. The switch to a 42-volt system would revolutionize the automotive industry. This would enable more electronic components and new technologies to be added to the vehicle. At the present time, the discussion and implementation of the 42-volt system is largely on luxury vehicles. The potential benefit of the system on heavy duty vehicles has not been fully explored.

Multi-Target tracking is a central aspect of modeling the surrounding environment of autonomous vehicles. Automotive millimeter-wave radar is a necessary component in the autonomous driving system. One of the biggest advantages of radar is it measures the velocity directly. Another big advantage is that the radar is less influenced by environmental conditions. It can work day and night, in rainy or snowy conditions. In the expressway scenario, the forward-looking radar can generate multiple objects, to properly track the leading vehicle or neighbor-lane vehicle, a multi-target tracking algorithm is required. How to associate the track and the measurement or data association is an important question in a multi-target tracking system. This paper applies the nearest-neighbor method to solve the data association problem and uses an extended Kalman filter to update the state of the track.

Car Periphery Supervision (CPS) systems comprise a family of automotive systems that are based on sensors installed around the vehicle to monitor its environment. The measurement and evaluation of sensor data enables the realization of several kinds of higher level applications such as parking assistance or blind spot detection. Although a lot of similarity can be identified among CPS applications, these systems are traditionally built separately. Usually, each single system is built with its own electronic control unit, and it is likely that the application software is bound to the controller's hardware. Current systems engineering therefore often leads to a large number of inflexible, dedicated systems in the automobile that together consume a large amount of power, weight, and installation space and produce high manufacturing and maintenance costs.

This paper proposed a collision avoidance strategy that take over the control of ego vehicle when faced with urgent collision risk. To improve the applicability of collision avoidance strategy in complex scenarios, the theory of ICS (Inevitable Collision State) is introduced to evaluate the collision risk and compute the trigger flag of the system, and vehicle dynamic is taken into account when modeling ego vehicle to predict ego vehicle’s following moving. Vehicle specific characteristics including reaction time of the braking system and the braking force increasing process are taken into account. In order to reduce injury caused by collision accidents and minimize disruption to drivers, slight steering is added on top of emergency braking. The direction of the steering angle is determined according to IM (Imitating Maneuvers) The flow chart of the strategy is presented in the paper.

An autonomous vehicle is able to perceive and interpret exactly its surroundings and its interior (“Sensing”). then, it processes the information received and plan its driving strategy (“processing”). And finally, it uses its powertrain, steering and braking power to move its wheels in such a way that the planned driving strategy is put into practice (“Acting”). Testing an autonomous vehicle’s reaction to the erratic traffic scenarios using prototypes would be impractical. Physically testing these scenarios can also be risky to human life and equipment. Additionally, the repetition involved in the comprehensive testing of all these scenarios could lead to human errors. Various Self Driving car manufacturers have reported injuries and causalities while doing Functional testing [1].

Autonomous vehicle is a vehicle capable of sensing its environment and taking decisions automatically with no human interventions. To achieve this goal, ADAS (Advance Driving Assistance System) technologies play an important role and the technologies are improving and emerging. The sensing of environment can be achieved with the help of sensors like Radar and Camera. Radar sensors are used in detecting the range, speed and directions of multiple targets using complex signal processing algorithms. Radar with long range and short range are widely used in the autonomous vehicles. Radar sensors with long range can be used to realize features like Adaptive Cruise Control, Advance Emergency Brake Assist. The short-range radar sensors are used for Blind Spot Monitoring, Lane Change Assist, Rear/Front Cross Traffic Alert and Occupant Safe Exit. To realize the Autonomous vehicle functionalities four short range radar sensors are required, two on front and two on rear (left and right).

Research in the development of assistive devices (power brakes, power steering, automatic transmission, etc.) is geared to close the gap between the handicapped and the normal operator. This objective is accomplished by providing additional assistive devices that will not interfere with the normal operation of the vehicle, but will enable the disabled individual safely to operate the same vehicle. This is achieved by considering the anthropometric and biomechanical constraints of the impaired driver. The pistol-grip controller is discussed in detail. It is intended to control manipulation of the steering wheel, brakes, lights, horn, windshield wiper, windows, etc.

Multi-sensor fusion strategies have gradually become a consensus in autonomous driving research. Among them, radar-camera fusion has attracted wide attention for its improvement on the dimension and accuracy of perception at a lower cost, however, the processing and association of radar and camera data has become an obstacle to related research. Our approach is to build a concise framework for camera and radar detection and data association: for visual object detection, the state-of-the-art YOLOv5 algorithm is further improved and works as the image detector, and before the fusion process, the raw radar reflection data is projected onto image plane and hierarchically clustered, then the projected radar echoes and image detection results are matched based on the Hungarian algorithm. Thus, the category of objects and their corresponding distance and speed information can be obtained, providing reliable input for subsequent object tracking task.

This paper describes a contactless differential torque sensor for use in a steering column of a vehicle having an all-electric power steering assist system. The basic concept of an eddy current surface-effect phase shift sensor is described along with its equivalent electrical circuit. A configuration giving low drift and good linearity is proposed. One low-cost method of exciting the sensor and demodulating the signal is shown. Characteristics, a block diagram of an overall electric assist steering system using the sensor and potential advantages of electric power steering are provided.

Advanced Driver Assistance Systems (ADAS) have become an inevitable part of most of the modern cars. Their use is mandated by regulations in some cases; and in other cases where vehicle owners have become more safety conscious. Vision / camera based ADAS systems are widely in use today. However, it is to be noted that the performance of these systems is depends on the quality of the image/video captured by the camera. Low illumination is one of the most important factors which degrades image quality. In order to improve the system performance under low illumination, it is required to first enhance the input images/frames. In this paper, we propose an image enhancement algorithm that would automatically enhance images to a near ideal condition. This is accomplished by mapping features taken from images acquired under ideal illumination conditions on to the target low illumination images/frames.

Today's automobiles contain a lot of electrical and electronic (E/E) systems with safety-related functionality. In a design-process compliant to the industrial standard ISO 26262 unknown dependencies between events and elements are risks that potentially violate safety requirements or safety goals. Therefore, the identification and analysis of dependent failures is important. Physical environment influences like temperature are one class of factors which can lead to coupling effects and cause dependent failures. In this paper we show a novel contract-based approach to deal with geometric installations of elements in an automobile. It avoids violations of safety requirements by identification and prevention of dependent failures resulting from coupling effects between elements. The influences of an element on environment factors and the failure effects of such environment factors on elements are explicitly specified as physical conditions.

Impact torque will be generated on the steering wheel when one tire suddenly blows out on high way, which may cause driver's psychological stress and result in driver's certain misoperations on the car. In this paper, the model of tire blowout vehicle was established; the tire blowout was detected based on the change rate of tire pressure, meanwhile, the rack force caused by tire blowout was estimated through a reduce observer; finally the compensation current was figured out to reduce the impact torque on the steering wheel. Results of simulation tests showed that the control strategy proposed in this paper can effectively reduce the impact torque on the steering wheel and reduce the driver's discomfort caused by tire blowout.

Electric power steering (EPS) systems utilize an electric motor to assist the driver’s steering efforts. Recently, EPS is drawing attention as a mechanism for improving vehicle stability and maneuverability. This paper proposes a control method using EPS to improve steering maneuverability when driving on rutted roads. The disturbance torque generated by the grooves in rutted roads affects maneuverability. Conventional EPS cannot discriminate between torque originating from driver input and aligning torque generated by the road surface. Thus, it is difficult for conventional EPS to reduce the unstable effect caused by ruts without affecting the driver’s steering feel. The method proposed here detects the amount of disturbance torque caused by the ruts in the road, and only when disturbance torque is detected, the EPS system compensates accordingly. As a result, steering pull is reduced without interfering with the driver’s steering feel.

Good road feel means that the driver can interpret road conditions through the steering wheel. This is one of the most important requirements demanded by car makers. However, over-sensitivity in steering transmission could cause inconvenience to the driver especially maneuvering on rough roads and hence must be isolated by the steering system or by other means. To overcome this, firstly we have to distinguish diverse road conditions and apply appropriate control strategy. In this paper we've proposed two control strategies to enhance steering performance on rough roads. The first method analyzes motor position signal of Electric Power Steering (or EPS) where the road roughness is separated from the motor position signal through signal processing. The roughness then is compensated for by using EPS to obtain a better steering feel. The second method utilizes CAN transferred vehicle information from Continuous Damping Control system (or CDC).

Recently steering technology focuses on not only driver's convenience, fuel efficiency, environment friendliness but also improved vehicle stability. Therefore Active Front Steering (AFS) has been widely studied as latest technical trend in steering system. This system can enhance vehicle stability by making additional road wheel angle (called ‘superimposed angle’) based on the vehicle state information such as vehicle speed, steering angle, yaw rate and lateral acceleration. While occurring superimposed steering angle, driver may feel the reaction torque which is caused from abnormal changes of steering effort with AFS mechanism installed. To solve this problem it is required to reduce steering output load in case of superimposed steering by increasing steering assist of rack assist type electric power steering. This paper describes the control method that is compensated reaction torque. And its effect of compensation is validated from test results