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Teleoperation can be regarded as an effectivebackup system for self-driving vehicles, which could take overvehicle control in some special scenarios that the automatedvehicles could not handle. However, there are still many challengesin teleoperation, such as low situation awareness. Thiscould potentially be dangerous in some extreme situations.However, it could be effectively improved by providing suitabledriving feedbacks. Hence, this article provides a timely andcomprehensive review of existing and possible driving feedbacktechniques in teleoperation. They are presented from the pointof view of video feedback, steering force feedback, motioncueingfeedback, audio and vibration feedback, and other nonconventionalfeedback modes. Then, the current challenges,future trends and opportunities in teleoperation are presentedand discussed. QC 20230613

Advanced active safety systems play a crucial role in ensuring the safe driving of vehicles in critical conditions such as an obstacle avoidance manoeuvre. However, conventional techniques relying mainly on braking interventions may not result in the desired vehicle response in such situations. Over-actuation through the control of individual motion actuators could potentially improve the safety performance of vehicles. This study evaluates various configurations of motion actuators for path following and yaw stability control of vehicles in critical driving scenarios. The configurations include active front steering (S), active front steering + torque vectoring (ST), active front steering + active camber (SC) and active front steering + torque vectoring + active camber (STC). The evaluation is achieved based on a nonlinear model predictive control formulation, which considers yaw stability and the physical limits of motion actuators. This problem formulation uses a double-track vehicle model, combined with the Dugoff tyre model and its variant with the camber effect, to model the vehicle dynamics. The actuator configurations are evaluated regarding the passing velocity, tracking accuracy, safety distance and robustness to reference trajectory variation. The results indicate that the integrated control of STC performs the best among all the four configurations while S performs the worst. Furthermore, SC is generally superior to ST. QC 20220523

This paper presents a test procedure developed to gather good quality data from objective and subjective testing on winter conditions. As the final goal of this test is to analyse the correlation between objective metrics and subjective assessments on winter for steering and handling, this procedure has to ensure a minimum change of the surface properties, which has a major influence on vehicle performance, during the whole test campaign. Therefore, the method presented keeps the total test time very low and allows similar vehicle configurations to be test- ed, objectively and subjectively, very close in time. Moreover, continuous maintenance work on the ice is performed. Reference vehicles are also used to monitor the changes on vehicle per- formance caused by weather conditions, which are inevitable. The method showed to be very effective. Initial results on objective metrics and subjective assessments are also presented. QC 20160404 iCOMSA

This study introduces a method for estimating the vehicle’s maximum entry speed for an ISO3888 part-2 double-lane change (DLC) test in simulation. Pseudospectral collocation in TOMLAB/ PROPT calculates the optimal steering angle that maximizes the entry speed. The rationale is to estimate the vehicle’s performance in the design phase and adapt the tuning to improve DLC ratings. A two-track vehicle dynamics model (VDM) employing non-linear tires, suspension properties and a simplified Dynamic Stability and Traction Control (DSTC) system was parameterized as a 2011 T5 FWD Volvo S60 using in-field tests and its corresponding kinematics and compliance (K&C) measurements. A sensitivity analysis on the parameters revealed certain trends that influence the entry speed, which can be varied from 69.4 up to 73.3 km/h when adapting certain vehicle features. To evaluate the method, the generated optimal steering control inputs for the simulated S60 were applied on the actual car motivating the further development of the method. QC 20150408

During development of new vehicles finding correlation links between subjective assessments and objective metrics is an important part in the vehicle evaluation process. Studying different correlation links is of importance in order to make use of the gained knowledge in the front end of development, during testing and for new systems. Both subjective assessments using the rating scale of 1-10 from expert drivers and objective metrics from different tests measured by a steering robot were collected by standard testing protocols at an automotive manufacturer. This paper evaluates driver ratings and analyse correlations by using Regression Analysis and Neural Networks through a case study approach. Links have been identified and are compared to related research. QC 20131007 iCOMSA

Platooning is a way to increase the traffic flow and capacity on roads to handle the upcoming problems of traffic congestion and exhaust emissions. The aim with this work is to evaluate if the safety distance of platooning vehicles can be further reduced when both lateral and longitudinal control is implemented. The idea is that when the vehicle in front suddenly brakes the vehicle behind, if needed, is steered aside while braking and stops beside the preceding vehicle. The analysis is performed using a game theoretical approach and different detailed vehicle models. Results show that the safety distance can be reduced. QC 20130611

The performance of cars has during recent years become increasingly dependent on complex electronic systems used especially for safety but also comfort, performance and informatics. Automotive winter testing activities in northern Sweden is vital to test and try out those systems. A contradiction to increased performance is that faulty software also causes 30 % of severe malfunctions in the functionality of the car. To deal with these problems, as early in the design process as possible, innovative methods to cope with digital abstraction and the physical world in a unified way seems promising. One useful approach, in automotive winter testing, might be to support the possibilities for real-time vehicle simulations of the car in motion. The closer collaboration in the automotive industry might be an incitement for investing in technologies for knowledge sharing. Besides enhancing the product development process, additional knowledge might support innovations. Today, instead of providing parts similar to their competitors and relying on one or two automakers, successful suppliers focus heavily on innovation and on collaboration with a number of manufacturers on a global market. Due to the possibilities to visualize whole processes, the use of simulations seems to support a' seeing first' approach to innovations. Thus, the purpose of this paper is to describe an as-is scenario and a to-be scenario for automotive winter testing to highlight how the use of real-time simulations facilitates innovative methods Validerad; 2007; 20070416 (tobias) Fastelaboratoriet – VINNEXC, CASTT - Centre for Automotive Systems Technologies and Testing

Increasing complexity of embedded systems in automotive industry calls for more efficient testing and verification processes. This paper presents a visualization application for distributed real-time vehicle validation. Real-time data from vehicles are transmitted via wireless network from the test track to a simulation framework. The processed data from the simulation are distributed to multiple web based visualization clients. The Java™ based client presents data in a rich 3D environment thus enabling non-expert to understand behaviors of complex vehicle systems. The application will contribute to enhanced validation data presentation and the ability to collaborate in a distributed real-time virtual environment. Godkänd; 2006; 20061127 (tobias);ISBN för värdpublikationen: 978-2-287-28772-5 CASTT - Centre for Automotive Systems Technologies and Testing

This paper presents a fault handling strategy for electric vehicles with four individual-wheel drives, which are based on wheel hub motors. The control strategy to handle the faults is based on the principle of control allocation and is implemented in an experimental vehicle. Experimental tests has been performed with the experimental vehicle and with simulation. The results show that the directional stability of such a vehicle can be improved for the analysed manoeuvre and failure mode, and the tendencies of the experimental results correspond with the simulation results. It has been found that the lateral and yaw motion could be strongly improved. QC 20161118