Extension of the Application Potential of Wheeled Mobile Driving Simulators to Uneven Grounds

Driving simulators are an important element of vehicle development, since the design of driver assistance systems in particular requires the investigation of the driver-vehicle interaction. In the future, an even greater application potential is to be expected with regard to automated driving, since, for example, handover strategies can be investigated in a secure environment. However, today's driving simulator concepts have reached a limit with regard to the achievable quality of motion simulation. Especially urban driving scenarios require a range of motion that is not economically viable with the sled systems applied in current high-end systems. One way out of this limitation is provided by wheeled mobile driving simulators, which generate the demanded accelerations through tire forces. This enables an application on different driving surfaces, which allows flexible adaptation of the movement area to the requirements of the scenario. However, due to the contact between tire and driving surface, unevenness induces vibrations into the system which disturb the immersion of the subject. The known previous research on wheeled mobile driving simulators gathered in literature neglected this aspect and postulated a sufficient driving surface quality. However, it is unclear what sufficient means in this context. In addition, the flexibility advantage of the concept may be significantly limited by the requirement of a high quality surface. Thus, this work aims at quantifying the required driving surface quality and the development and evaluation of approaches for the reduction of disturbances induced by unevenness. First, an analysis of the current development state of the driving simulator at FZD, which includes a purely tire-sprung system with solid rubber tires, is conducted. This analysis shows that driving surface qualities with a maximum height deviation of 0.01 mm over a length of 4 m (so-called depth gauge) are required to use a driving simulator of this configuration without deteriorating the immersion of the subject. This quality is not achievable with asphalt surfaces, which offer the highest application potential for WMDS. The minimum achievable depth gauge amounts to 2 mm. Thereupon, an active compensation of the driving surface-induced vibrations with the Hexapod, which is already available in simulators, is investigated. The active approach increases the tolerable depth gauge by a factor of 4 compared to the passive tire-sprung system. Nevertheless, it is still only 3 % of the target value. Especially the high dead time of the hexapod as well as the low damping and the parameter fluctuations of the tire limit the potential of the concept. Therefore, the potential of implementing an additional suspension in combination with the active approach is investigated. In order to achieve a low natural frequency, which is advantageous in terms of vibration isolation, a kinematics is developed that reduces the suspension movements of the omnidirectional motion platform by support forces. In addition, the motion control of the driving simulator is adapted in order to adjust the wheel force distribution to the demands of the suspension. These measures reduce the disturbances caused by suspension movements to values below the perception threshold up to a horizontal acceleration of 4.5 m/s². The simulation of an urban driving scenario with a multibody model shows that this covers the majority of the occurring accelerations and that within more than 99% of the simulation time the disturbance motions remain below the perception threshold. With pneumatic tires, the acceleration range with ideal support can be increased to 5.4 m/s². With regard to the required driving surface quality, this allows an increase of the acceptable depth gauge to 0.8 mm, which corresponds to an improvement of almost two orders of magnitude compared to the initial situation. Nevertheless, the value is slightly below the minimum of 2 mm achievable with asphalt surfaces. However, the determined value is only required to remain below the perception threshold with the disturbance vibrations. As vibration in vehicles is not uncommon, the negative effects on the immersion could possibly be lower, allowing a slight exceeding of the threshold. Future subject studies must examine this aspect in more detail

Vehicle and Traffic Safety

The book is devoted to contemporary issues regarding the safety of motor vehicles and road traffic. It presents the achievements of scientists, specialists, and industry representatives in the following selected areas of road transport safety and automotive engineering: active and passive vehicle safety, vehicle dynamics and stability, testing of vehicles (and their assemblies), including electric cars as well as autonomous vehicles. Selected issues from the area of accident analysis and reconstruction are discussed. The impact on road safety of aspects such as traffic control systems, road infrastructure, and human factors is also considered

The Crewman's Associate for Path Control (CAPC): an automated driving function

Army Tank Automotive Command, Warren, Mich.http://deepblue.lib.umich.edu/bitstream/2027.42/1134/2/88210.0001.001.pd

Haptic Steering Interfaces for Semi-Autonomous Vehicles

Autonomous vehicles are predicted to significantly improve transportation quality by reducing traffic congestion, fuel expenditure and road accidents. However, until autonomous vehicles are reliable in all scenarios, human drivers will be asked to supervise automation behavior and intervene in automated driving when deemed necessary. Retaining the human driver in a strictly supervisory role, however, may make the driver complacent and reduce driver's situation awareness and driving skills which ironically, can further compromise the driver’s ability to intervene in safety-critical scenarios. Such issues can be alleviated by designing a human-automation interface that keeps the driver in-the-loop through constant interaction with automation and continuous feedback of automation's actions. This dissertation evaluates the utility of haptic feedback at the steering interface for enhancing driver awareness and enabling continuous human-automation interaction and performance improvement in semi-autonomous vehicles. In the first part of this dissertation, I investigate a driving scheme called Haptic Shared Control (HSC) in which the human driver and automation system share the steering control by simultaneously acting at the steering interface with finite mechanical impedances. I hypothesize that HSC can mitigate the human factors issues associated with semi-autonomous driving by allowing the human driver to continuously interact with automation and receive feedback about automation action. To test this hypothesis, I present two driving simulator experiments that are focused on the evaluation of HSC with respect to existing driving schemes during induced human and automation faults. In the first experiment, I compare obstacle avoidance performance of HSC with two existing control sharing schemes that support instantaneous transfers of control authority between human and automation. The results indicate that HSC outperforms both schemes in terms of obstacle avoidance, maneuvering efficiency, and driver engagement. In the second experiment, I consider emergency scenarios where I compare two HSC designs that provide high and low control authority to automation and an existing paradigm that decouples the driver input from the tires during collision avoidance. Results show that decoupling the driver invokes out-of-the-loop issues and misleads drivers to believe that they are in control. I also discover a `fault protection tradeoff': as the control authority provided to one agent increases, the protection against that agent's faults provided by the other agent reduces. In the second part of this dissertation, I focus on the problem of estimating haptic feedback from the road, or the road feedback. Road feedback is critical to making the driver aware of the state of the vehicle and road conditions, and its estimates are used in a variety of driver assist systems. However, conventional estimators only estimate road feedback on flat roads. To overcome this issue, I develop three estimators that enable road feedback estimation on uneven roads. I test and compare the performance of the three estimators by performing driving experiments on uneven roads such as road slopes and cleats. In the final part of this dissertation, I shift focus from physical human-automation interaction to human-human interaction. I present the evidence from the literature demonstrating that haptic feedback improves the performance of two humans physically collaborating on a shared task. I develop a control-theoretic model for haptic communication that can describe the mechanism by which haptic interaction facilitates performance improvement. The model creates a promising means to transfer the obtained insights to design robots or automation systems that can collaborate more efficiently with humans.PHDMechanical EngineeringUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/169975/1/akshaybh_1.pd

Becoming Human with Humanoid

Nowadays, our expectations of robots have been significantly increases. The robot, which was initially only doing simple jobs, is now expected to be smarter and more dynamic. People want a robot that resembles a human (humanoid) has and has emotional intelligence that can perform action-reaction interactions. This book consists of two sections. The first section focuses on emotional intelligence, while the second section discusses the control of robotics. The contents of the book reveal the outcomes of research conducted by scholars in robotics fields to accommodate needs of society and industry

Proceedings of the ECCOMAS Thematic Conference on Multibody Dynamics 2015

This volume contains the full papers accepted for presentation at the ECCOMAS Thematic Conference on Multibody Dynamics 2015 held in the Barcelona School of Industrial Engineering, Universitat Politècnica de Catalunya, on June 29 - July 2, 2015. The ECCOMAS Thematic Conference on Multibody Dynamics is an international meeting held once every two years in a European country. Continuing the very successful series of past conferences that have been organized in Lisbon (2003), Madrid (2005), Milan (2007), Warsaw (2009), Brussels (2011) and Zagreb (2013); this edition will once again serve as a meeting point for the international researchers, scientists and experts from academia, research laboratories and industry working in the area of multibody dynamics. Applications are related to many fields of contemporary engineering, such as vehicle and railway systems, aeronautical and space vehicles, robotic manipulators, mechatronic and autonomous systems, smart structures, biomechanical systems and nanotechnologies. The topics of the conference include, but are not restricted to: ● Formulations and Numerical Methods ● Efficient Methods and Real-Time Applications ● Flexible Multibody Dynamics ● Contact Dynamics and Constraints ● Multiphysics and Coupled Problems ● Control and Optimization ● Software Development and Computer Technology ● Aerospace and Maritime Applications ● Biomechanics ● Railroad Vehicle Dynamics ● Road Vehicle Dynamics ● Robotics ● Benchmark ProblemsPostprint (published version