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In this paper a novel adaptive regenerative braking control concept for electric vehicles with an electric motor at the front axle is presented. It is well known that the "phased" type regenerative braking systems of category B maximize the amount of regenerative energy during braking. However, there is an increased risk of maneuvering capability loss especially during cornering. An integrated braking controller which determines - in a single step - the desired yaw moment and allocates the braking demand between hydraulic brakes and electric motor during cornering is designed using the State Dependent Riccati Equation (SDRE) method. A unique method for deriving the State Dependent Coefficient (SDC) formulation of the system dynamics is proposed. Soft constraints are included in the state dynamics while an augmented penalty approach is followed to handle hard constraints. The performance of the controller has been evaluated for different combined cornering-braking scenarios using simulations in a Matlab/Simulink environment. For this an eight degrees of freedom (DOF) nonlinear vehicle model has been utilized. The numerical results show that the controller is able to optimize (locally) the amount of regenerative braking energy while respecting system's constraints such as tire force saturation, vehicle yaw rate and slip angle errors.

For the virtual development of steering systems, especially those including electric power steering systems (EPS or EPAS), it is required to have a tyre model that accurately predicts the forces and moments at standstill and manoeuvring at low velocities. This means that the tyre model must be able to deal with combined slip situations of spin, sideslip and longitudinal slip, not only for steady-state, but also for transient behaviour. Recently, TNO updated the turn slip theory originally developed by Pacejka in the latest MF-Swift 6.2 tyre model. Extensive validation with measurements has however been lacking, as suitable tyre test facilities are unavailable. Generally the ‘standard’ centre-point steering experiment is used for parameter identification and model validation. Drawback of this test approach is that only a limited operating range is considered and only a few parameters can be identified. In this study, the applicability of the turn slip model for realistic parking manoeuvres is assessed using vehicle measurements and simulations.

The Integrated Vehicle Safety Department of TNO (Dutch Organization for Applied Scientific Research) investigates the application of modern control methods in the Integrated Vehicle Dynamics Control (IVDC) field, as a strategic research topic of the Beyond Safe framework. The aim of IVDC is to optimize the vehicle performance by maximizing the synergy between vehicle system like braking, suspension and steering systems and thereby enable improvements in the vehicle safety and comfort for all driving conditions. This article presents the first steps undertaken by the authors to develop and experimentally evaluate an optimal IVDC strategy for stability control using only the braking system. More specifically it presents the structure of the controller, the vehicle and tire models used, the State Dependent Riccati Equation (SDRE) control technique and the experimental evaluation.

Future mobility requires sound solutions in the field of fault tolerance in real-time applications amongst which Cooperative Adaptive Cruise Control (CACC). This control system cannot rely on the driver as a backup and is constantly active and therefore more prominent to the occurrences of faults (such as packet loss in the wireless communication). This paper presents an algorithm which uses the availability of sensor-data in each moment in time to calculate in real-time a safe distance for the CACC system. This safe distance consists of a velocity dependent part and a constant part, both important settings in the spacing policy for the CACC. A critical scenario for which CACC should still be functional is chosen, mathematical models of the system response are derived and errors are modeled. The model enables the calculation of differences in braking distances, which leads to a required safe distance. This approach makes the dynamic algorithm useful for sensor faults. The algorithm is implemented in a test vehicle and test results are presented. © 2013 IEEE.

Structural interaction has been one of the critical issues for improved frontal impact protection. An evaluation procedure for structural interaction has been difficult to develop using objective test data procedures. While previous research with the PDB barrier has been promising based on subjective evaluations, an objective assessment criteria has been elusive. Part of the EU project FIMCAR focused on the development of an assessment procedure to assess important frontal impact characteristics like load spreading. Test and simulation data from vehicle impacts with the PDB or MPDB were collected for different vehicle models, spanning a range of vehicle masses and vehicle classes. Available car-to-car crash tests were also collected for reference. The main information analyzed w.r.t. the assessment of load spreading was the deformation pattern of the PDB barrier after a test. These deformation plots were reviewed and subjectively assessed by experts. The subjective assessments were used to develop key characteristics that should be detected by a numerical assessment of the 3D data. These subjective assessments were then compared to different objective (numerical) assessments for the barriers to ensure correlation of the results and then validated with available car-car data. Assessment of the influence of assessment area and scanning resolution were also performed. The deformation profiles could be grouped into three main groups where the horizontal and vertical load spreading distinguished vehicles with vehicles to be assessed and be updated to also assess vertical load spreading.

Vehicle occupant behavior in emergency driving conditions has a large effect on traffic safety. Distraction is estimated to be the cause of 15-20% of all crashes. Additionally, the posture of the occupants prior to the possibly unavoidable crash is known to have a large effect on the injury reducing performance of the restraint system. In this study it is investigated whether braking settings as well as driver distraction influence the kinematic response of an occupant during braking events, in order to improve the design of crash avoidance or crash and injury mitigation systems.

Integrated vehicle safety systems that combine elements from primary and secondary safety have a high potential to improve vehicle safety, due to their ability to influence crash conditions and/or to adapt to these crash conditions. So far no standard evaluation procedures have been developed and implemented. The main goal of the ASSESS project is to develop harmonized and standardized assessment procedures for related collision mitigation and avoidance systems. Procedures are developed for: (1) Driver behavior evaluation (2) Pre-crash system performance evaluation (3) Crash performance evaluation (4) Socio-economic assessment. This paper presents the activities related to the "Pre-Crash evaluation". The objective is to provide a tool box for the specific evaluation of the pre-crash performance of collision mitigation and avoidance systems and their contribution to the overall system performance. cop. Springer-Verlag 2013.

Der Schutz schwacher Verkehrsteilnehmer wie Fußgänger und Fahrradfahrer erfordert weitere Innovationen. Gemeinsam mit Autoliv entwickelte die niederländische TNO dazu den Prototyp eines neuartigen Windschutzscheibenairbags sowie eine Erweiterung der Notbremsfunktion.

Past European collaborative research involving government bodies, vehicle manufacturers and test laboratories has resulted in a prototype barrier face called the Advanced European Mobile Deformable Barrier (AE-MDB) for use in a new side impact test procedure. This procedure offers a better representation of the current accident situation and, in particular, the barrier concept is a better reflection of front-end stiffness seen in today’s passenger car fleet compared to that of the current legislative barrier face. Based on the preliminary performance corridors of the prototype AE-MDB, a refined AE-MDB specification has been developed. A programme of barrier to load cell wall testing was undertaken to complete and standardise the AE-MDB specification. Barrier faces were supplied by the four leading manufacturers to demonstrate that the specification could be met by all. This paper includes background, specification and proof of compliance.

The current paper shows string stability of a platoon of vehicles when the spacing policy within the platoon is dynamic, i.e., it has time-varying parameters. This problem setup is to address the safety issues that arise due to malfunction of some redundant sensing/communicating devices installed on the vehicles. In such a faulty situation, the controller is still functional due to the redundancy of the sensing/communicating devices as well as estimating resources which provide the controller with the required information. However, the accuracy of the controller will be reduced. This loss of accuracy should be compensated by doing a more conservative design of safety important parameters such as the safe inter-vehicle distance, which is selected based on the string stability requirement. The decision of a change in the inter-vehicle distance, or equivalently the spacing policy, is made by a so called 'safety checker' function which can be introduced into the loop of vehicle and controller. Here, it is shown that an adopted cooperative adaptive cruise controller renders the string of vehicles stable even if the spacing policy is time variant. The stability requirement of the closed-loop system is that the switching signal suggested by the safety checker unit being piecewise constant, i.e., the safe inter-vehicle distance policy does not change continuously. © 2013 IEEE.

Cooperative Adaptive Cruise Control (CACC) employs wireless intervehicle communication, in addition to onboard sensors, to obtain string-stable vehicle-following behavior at small intervehicle distances. As a consequence, however, CACC is vulnerable to communication impairments such as packet loss, in which case it would effectively degrade to conventional Adaptive Cruise Control (ACC), thereby increasing the minimal intervehicle distance needed for string-stable behavior. Therefore, a control strategy for graceful degradation of one-vehicle look-ahead CACC is proposed to partially maintain the string stability properties of CACC. This strategy is based on estimating the preceding vehicle's information, here acceleration, using the onboard sensors. Whenever needed, this estimated acceleration can be used as an alternative to the desired acceleration transmitted through wireless communication for this type of CACC. It is shown through simulations and experiments that the proposed strategy results in a noticeable improvement of string stability characteristics, when compared to the situation in which ACC is used as a fallback scenario. © 2013 IEEE.

The severity of occupant injuries sustained during automotive collisions can increase when an occupant is out‐of‐position prior to the crash. Several studies have shown that muscle activation significantly affects human kinematics in low severity impacts or pre‐crash car movements. As such, it is important to quantify the influence of this behaviour to effectively design safety systems. Reactive behaviour can be simulated with a recently developed computer human model that stabilises to a predefined position. The objective of this study was to adapt this model to simulate realistic bracing behaviour during braking. A new neck model was developed as well as a new arm model. In an anterior‐posterior frequency perturbation test the new neck model showed a more comparable response to that of a volunteer than the previous model. In arm pulse perturbation tests the new arm model showed comparable behaviour to a volunteer in relaxed as well as in braced conditions. Finally, a simulation of a braking event with the new active human model showed that bracing has a substantial effect on the head and thorax displacement. It is concluded that the new neck and new arm model improved the active human model for the development of active safety systems.

Software is becoming an important part of the innovation for vehicles. In addition, the systems in vehicles become interconnected and also get external connections, to the internet and Vehicular Ad hoc NETworks (VANETs). These trends form a combined security and safety threat, because recent research has demonstrated a large number of security gaps for in-vehicle systems and their external connections. This overview paper presents attacker incentives and the most important security risks that are identified for the parts that make up a cooperative mobility system. For cooperative systems, the application data integrity must be validated to determine if values can be trusted. Furthermore, secure alternatives will be required for positioning, in order to be usable by safety critical systems. To create a secure in-vehicle system, it should be secure by design. In addition to the technical challenges, overarching cyber security dilemmas are addressed, such as stimulating the economy vs. improving security. We expect that the discussed risks will be a challenge for research, industry and authorities in the coming years.

This paper considers the optimal control problem for a class of infinite-dimensional systems, namely spatially invariant systems. A common assumption in the scope of such optimal control problem is the exponential stabilizability of the infinite-dimensional plant. We propose sufficient conditions for the optimizability of spatially invariant systems that are not exponentially stabilizable. The practical significance of this problem setting is motivated by vehicular platooning, for which it is desired to design controllers that attenuate the effect of disturbances, both in time and space, i.e., over the vehicle index.

Objective: To improve vehicle safety in frontal collisions, the crash compatibility between the colliding vehicles is crucial. Compatibility aims to improve both the self and partner protection properties of vehicles. Although compatibility has received worldwide attention for many years, no final assessment approach has been defined. Methods: Within the Frontal Impact and Compatibility Assessment Research (FIMCAR) project, different frontal impact test procedures (offset deformable barrier [ODB] test as currently used for Economic Commission for Europe [ECE] R94, progressive deformable barrier test as proposed by France for a new ECE regulation, moveable deformable barrier test as discussed worldwide, full-width rigid barrier test as used in Federal Motor Vehicle Safety Standard [FMVSS] 208, and full-width deformable barrier test) were analyzed regarding their potential for future frontal impact legislation. The research activities focused on car-to-car frontal impact accidents based on accident investigations involving newer cars. Test procedures were developed with both a crash test program and numerical simulations. Results: The proposal from FIMCAR is to use a full-width test procedure with a deformable element and compatibility metrics in combination with the current offset test as a frontal impact assessment approach that also addresses compatibility. Conclusions: By adding a full-width test to the current ODB test it is possible to better address the issues of structural misalignment and injuries resulting from high acceleration accidents as observed in the current fleet. The estimated benefit ranges from a 5 to 12 percent reduction of fatalities and serious injuries resulting from frontal impact accidents. By using a deformable element in the full-width test, the test conditions are more representative of real-world situations with respect to acceleration pulse, restraint system triggering time, and deformation pattern of the front structure. The test results are therefore expected to better represent real-world performance of the tested car. Furthermore, the assessment of the structural alignment is more robust than in the rigid wall test. Supplemental materials are available for this article. Go to the publisher's online edition of Traffic Injury Prevention to view the supplemental file. © 2013 Copyright TF.

Active safety systems that start to act moments before the crash might be capable of anticipating the occupant’s position, either by correcting it, or by taking the out-of-position into account. For the development and evaluation of such active safety systems, recently a run-time efficient multidirectional computer human model that can simulate active as well as passive human behaviour has been developed. The objective of this study was to evaluate this so-called active human model for simulations of braking followed by a frontal crash.

The driving range of electric vehicles can be extended using regenerative braking. Regenerative braking uses the elctric drive system, and therefore only the driven wheels, for decelerating the vehicle. Braking on one axle affects the stability of the vehicle, especially for road conditions with reduced friction. This paper discusses three control strategies for preventing loss of stability while applying regenerative braking, two of which are using a state estimation algorithm developed by TNO. Experiments have been conducted with a front wheel driven vehicle on a low friction test track. However the conclusions concerning the control concepts are based on simulation results, due to unexpected system behaviour of the test vehicle. The results also indicate that the effectiveness of regenerative braking can be improved in cornering situations by using the vehicle yaw rate as a control signal. Due to hardware limitations, it has not been possible to rank the performance of the individual regenerative braking controllers in practice. It is recommended to further study the control concepts using an improved hardware setup.

Development and experimentally evaluation of an optimal Vehicle Dynamic Control (VDC) strategy based on the State Dependent Riccati Equation (SDRE) control technique is presented. The proposed nonlinear controller is based on a nonlinear vehicle model with nonlinear tire characteristics. A novel extended linearization scheme of the system's state space equations on the basis of the combined slip Pacejka tire model is developed. On-line control regulation in terms of optimal braking torque allocation is computed at each time increment by solving efficiently an Algebraic Riccati Equation. The proposed method is implemented and tested on a Jaguar XF test vehicle. The results show the effectiveness of the proposed controller in stabilizing the vehicle with less effect on the vehicle longitudinal motion. © 2013 AACC American Automatic Control Council.

Cooperative systems are being developed for large scale deployment in the near future. Validation of the performance of cooperative systems, and evaluation of the impact of cooperative applications is crucial before large scale deployment can proceed. The DITCM test site facilitates testing, evaluation, and validation of cooperative systems in normal traffic. The test site spans the urban roads in two cities and the connecting motorway. This paper presents the architecture of the road side facilities and its compliance to standards. It also shows the flexibility to configure the facilities to a wide range of validation and evaluation setups in a series of international and national projects. © 2013 IEEE.

The application of a single track vehicle model to describe the lateral vehicle dynamics is common for control applications. As a result of simplifications, the basic single track vehicle model uses different front and rear effective tyre characteristics, which are valid for one loading configuration only. A study is conducted for parameter identification of an enhanced single track model that uses a single tyre description for both axles. Accurate results are obtained using experimental data from steady state cornering, pseudo-random steer and lane change manoeuvres for two loading configurations. The identification method has been validated for 15 different vehicles, and the results show that the response is within the confidence interval of measured step steer vehicle responses. It is concluded that the proposed single track model is generally suitable for describing the vehicle response for different loading configurations when load dependencies are included in the tyre description and vehicle inertia properties.

Integrated vehicle safety systems that combine elements from primary and secondary safety have a high potential to improve vehicle safety, due to their ability to influence crash conditions and/or to adapt to these crash conditions. So far no standard evaluation procedures have been developed and implemented. The main goal of the ASSESS project is to develop harmonized and standardized assessment procedures for related collision mitigation and avoidance systems. Procedures are developed for: · Driver behavior evaluation; · Pre-crash system performance evaluation; · Crash performance evaluation; · Socio-economic assessment. This paper presents the activities related to the “Pre-Crash evaluation”. The objective is to provide a tool box for the specific evaluation of the pre-crash performance of collision mitigation and avoidance systems and their contribution to the overall system performance.

Active safety systems that start to act moments before the crash might be capable of anticipating the occupant’s position, either by correcting it, or by taking the out-of-position into account. To develop such active safety systems, computer simulations of the occupant’s pre-crash behaviour are very valuable in determining system performance. The objective of this study was to develop a run-time efficient computer human model that can simulate active as well as passive human behaviour such that it can be used to simulate the pre-crash and in-crash phase in one simulation run. The so-called active human model is a multi-body model, and is based on earlier developed human models in MADYMO and techniques for controlled active behaviour. The model’s responses in a 1 g car braking, 15 g frontal, 7 g lateral and 3.6 g rear impact were compared to that of the volunteers. It was concluded that the active human model with controlled active behaviour with co-contraction of the neck muscles better predicts the behaviour of the volunteers than without co-contraction or completely passive behaviour. With the best fitting co-contraction levels and reaction times the maximum deviation from the average peak responses of the volunteers was at most 20%.

The protection of vulnerable road users (VRU) remains one of the most challenging problems for our society and several governmental and consumer organization has set targets to reduce the VRU fatality and injury rates. The automotive industry is, therefore, developing pedestrian and cyclist detection systems that combine pre-crash sensing, risk estimation and vehicle dynamics control (braking, steering) with the objective to meet the challenging VRU accident reduction targets set by various governments. The complexity of VRU detection makes the development process of these systems a complicated and time-consuming activity. Simulation software can help to overcome these difficulties by providing an efficient and safe environment for designing and evaluating VRU safety systems. This paper outlines the use of a software packages that provide the ability to cover all critical aspects of VRU safety design. It focuses on the sensing and control systems, as well as the evaluation of these systems for a range of different traffic scenarios. The presented system model uses fused information from radar model for collision estimation and vision sensor model for object classification, to deploy autonomous braking and thus mitigate the effect of collision with VRUs. © 2012 IEEE.

Frontal collisions between cars and trucks lead to high fatality rate of the car driver. Therefore the Japanese road administration announced a directive like ECE-R 93 (2000/40/EC), compulsory since September 1st, 2011. As known, this directive describes a ‘rigid’ Front Underrun Proctection (FUP) device installed underneath a truck. However, more lives can be saved when installing an energy absorbing device. In order to evaluate the effect of this device, a new evaluation method is needed. A practical evaluation method is to carry out a car to truck collision test and to evaluate the injury of the dummy inside the car. But this test is rather complicated and quite expensive. The authors made an investigation to remove the dummy from the car and to use the signals obtained from the car for determination of the crash severity and to evaluate the effect of the e. a. FUP device. Furthermore, an outlook to replace the car by a more generic device, e. g. by use of a Moving Progressive Deformable Barrier, has been considered.

The challenge of designing stability control functions for trucks is to guarantee robustness for all variations in truck and trailer combinations. The method proposed in this study can be used to quickly narrow down the number of truck and trailer combinations to a critical set to be evaluated with complex nonlinear simulation software or full-scale tests. To reach this goal, equations of motion are derived for single track linear vehicle models to understand the fundamental differences between the dynamic yaw performance of the truck and trailer combinations. The Hurwitz criterion is used to determine approximate analytical stability boundaries. It is shown that stability does not provide discrimination between combinations as most combinations are stable during normal driving conditions. In contrast, rearward amplification is a discriminatory performance measure. A frequency domain approach is used to study the fundamental differences between vehicle combinations. A comparison with complex nonlinear simulation model results indicates that the proposed method can be used to select critical vehicle combinations and to study the effect of parameter changes. © 2012 Copyright Taylor and Francis Group, LLC.

For the development of effective vehicle-related safety solutions to improve cyclist and pedestrian protection, essential information on impact locations, impact situations and cyclist and pedestrian kinematics in impacts with passenger cars is fundamental. Accidentology research showed that cyclists typically have a higher impact location, with a larger share of injuries from the windscreen area . Majority of accidents happened at crossroads (72% of the Dutch cases). The average car speed was 36 kph, the median bicycle speed 14 kph. A cyclist simulation study captured kinematics and injuries to head, torso, pelvis and legs for several human body sizes, bicycle types and generic car models. Six full-scale crash tests (passenger car versus cyclist or pedestrian (Polar II dummy) had as main parameters: head impact location (top of bonnet, windscreen, A-pillar), vehicle speed (40 kph) and dummy speed (15 kph). Accidentology, simulation and crash test data showed that the windscreen is a frequent head and torso impact location. Accidentology and crash testing showed that cyclist protection should address higher, more rearward locations in the windscreen area than pedestrian countermeasures. Head impact speeds for cyclists in testing were generally higher than for pedestrians.

Recent development in wireless technology enables communication between vehicles. The concept of cooperative adaptive cruise control (CACC)–which uses wireless communication between vehicles–aims at string stable behavior in a platoon of vehicles. “String stability” means any non-zero position, speed, and acceleration errors of an individual vehicle in a string do not amplify when they propagate upstream. In this article, we will discuss the string stability of CACC and evaluate its performance under varying packet loss ratios, beacon sending frequencies, and time headway settings in simulation experiments. The simulation framework is built up with a controller prototype, a traffic simulator, and a network simulator.

A map based controller method to improve a vehicle lateral stability is proposed in this study and compared with the conventional method, a model referenced controller. A model referenced controller to determine compensated yaw moment uses the sliding mode method, but the proposed map based controller uses compensated yaw moment map acquired by vehicle stability analysis. Vehicle stability region is calculated by topological method based on trajectory reversal method. A two degree-of-freedom vehicle model and Pacejkas tire model used to evaluate the proposed map based controller. The control performance of two methods are compared under various road conditions and driving inputs. Model referenced control method needs control input to satisfies linear reference model, and then generates unnecessary tire lateral forces, it may lead to worse performance than uncontrolled vehicle with step steer input in low friction road. As the results of simulation, map based controller seems to be better than model referenced in the viewpoint of stability. © 2012 IEEE.

This paper presents a combined control and estimation framework for energy recuperation in fully electric vehicles. We consider a fully electric powertrain, with a driven front axle operating on low friction road surfaces. Our objective is to find the blending of regenerative and friction braking that maximizes the amount of recovered energy (i.e., the regenerative braking), while (i) delivering the total braking force requested by the driver, (ii) preserving the yaw stability as well as driveability of the vehicle. The proposed framework, which consists of a predictive braking control algorithm and a vehicle state and parameters estimator, is appealing because it requires minimal re-design efforts in order to cope with different powertrain layouts (e.g., individual wheel motors) and/or control objective and design and physical constraints. We present simulation results, obtained in three sets of manoeuvres, showing promising results in terms of energy recuperation, vehicle stability and driveability.

Om het aantal doden en gewonden onder fietsers in het verkeer te laten dalen werkt TNO aan verschillende projecten: Samen met I&M en RWS onderzoekt TNO de oorzaak van enkelvoudige fietsongevallen en fiets/fiets ongevallen. Analyse van videobeelden van gevaarlijke locaties biedt inzicht in welk gedrag tot dit type ongevallen leidt. De helft van het aantal fietsdoden komt door aanrijdingen tussen auto’s en fietsers. Het SaveCAP project, een samenwerking van TNO met partners, onderzoekt de mogelijkheden van veiligheidsmaatregelen, zoals een airbag aan de buitenzijde of automatisch remmen. November 2012 zal een “proof-of-concept” worden gepresenteerd. Het is belangrijk dat maatregelen in voertuigen ter verbetering van de bescherming van voetgangers en fietsers zoveel mogelijk worden toegepast. Daarom werkt TNO in het project AsPeCSS in een Europees consortium aan een beoordelingssysteem van deze maatregelen.

In May 2011, the Grand Cooperative Driving Challenge (GCDC) was held, providing the possibility for teams to develop and compare their cooperative driving solutions in a competitive setting. The challenge was organized to further accelerate developments in the area of cooperative driving. Nine international teams challenged each other to handle both an urban and a highway scenario. These scenarios have been chosen such that the performance of the implementation of cooperative adaptive cruise control of each participant can be judged. Evaluation of the vehicle behavior has been performed by means of video-based roadside units, installed at the test site in The Netherlands, that is capable of tracking the individual vehicles, in addition to the information obtained through wireless communication. Judgement criteria include both macroscale criteria, such as platoon length and traffic light throughput, and individual criterion, like string stability. Most teams performed well, although clear differences in performance and reliability could be observed. The GCDC showed that it is possible to cooperatively drive with heterogeneous systems. It is envisioned to make the GCDC a regular event and to further extend the active role of roadside communication units, as well as include automated lateral vehicle control.

Based on the test scenarios and target specifications as described in the ASSESS deliverable D4.2 “Draft test and assessment protocol” a second series of pre-crash evaluation tests have been carried out by BAST, IDIADA, TNO and DAIMLER. Like in the first series of test conducted by BASt and IDIADA within the second series only rear-end manoeuvres were conducted. This was in line with the specifications of the test vehicles and the available laboratory equipment. The main objective of the second series was to check the reproducibility and repeatability of the specified test program and the capability of the various laboratories with the newly implemented laboratory updates as realized within the ASSESS project.

Im Rahmen des im 7. Forschungsrahmenprogramm der Europäischen Kommission geförderten Projekts „ASSESS“ wurde ein modulares Bewertungssystem für Systeme der aktiven Sicherheit erstellt und anhand von serienmäßigen Notbremssystemen getestet. Im Fahrversuch wurden Warnzeitpunkt, Bremszeitpunkt und Geschwindigkeitsreduktion serienmäßiger Fahrzeuge bestimmt. Dabei kamen zwei verschiedene Zielobjekte und vier verschiedene Ansätze zur Bewegung des Zielobjekts zum Einsatz. Die von den verschiedenen Testinstituten bestimmten Ergebnisse und die Streuungen der einzelnen Messungen sind vergleichbar – für eines der beiden Testfahrzeuge liegen die Streuungen, insbesondere bei Kennwerten für Warn- und Bremszeitpunkt, im Bereich von 2% des jeweiligen Mittelwertes. Die Streuungen der Beschwindigkeitsreduktion liegen höher, sind aber ebenfalls vergleichbar. Geringe Unterschiede zwischen zwei Gruppen von Testinstituten lassen sich durch Eigenschaften des verwendeten Zielobjekts beziehungsweise Eigenschaften des verwendeten Testfahrzeugs (RADAR-Kalibrierung) erklären. Zusätzlich bestimmte Warnzeitpunkte eines der beiden Fahrzeuge bei Auffahrt auf einen realen Pkw liegen gut im Bereich der mit synthetischen Zielobjekten gemessenen Zeiten. Aus diesen Erkenntnissen wird abgeleitet, dass das Testverfahren grundsätzlich geeignet ist, reproduzierbar und wiederholbar die Bremsleistung eines mit Notbremsfunktion ausgerüsteten Fahrzeugs zu messen. Erreichte Wiederholgenauigkeiten von ± 1 km/h für die jeweiligen Geschwindigkeiten und ± 30 cm für den seitlichen Abstand haben sich als ausreichend erwiesen. Die in Feld- und Simulatorversuch ermittelte Fahrerreaktion, die durch einen relativ geringen Bremspedalkraftgradienten gekennzeichnet ist, hat sich als simulierte Fahrerreaktion so nicht bewährt. Wesentlicher Grund dafür ist die Regelgüte und die erforderliche Abstimmungsarbeit herkömmlicher Bremspedalaktorik. Das Konsortium ist sich aber einig darin, dass eine simulierte Fahrerreaktion erforderlich ist, um die Sicherheitswirkung eines Notbremssystems umfassend zu bewerten. Ansätze hierfür könnten die in anderen Konsortien entwickelten Fahrerreaktionen sein. Detailliertere Ergebnisse des ASSESS-Projekts finden sich auf der Website www.assessproject.eu.

The CityMobil project “Towards advanced transport for the urban environment” aims at achieving a more effective organisation of urban transport, resulting in a more rational use of motorised traffic with less congestion and pollution, safer driving, a higher quality of living and an enhanced integration with spatial development. This paper describes a certification procedure for automated transport systems, developed in various European research projects and completed in the CityMobil project. The paper also describes the first experiences with the procedure. Furthermore the paper describes experiences with certification processes of automated systems in various countries where systems have been introduced.

TNO is an independent research organisation whose expertise and research make an important contribution to the competitiveness of companies and organisations, to the economy and to the quality of society as a whole. TNO’s unique position is attributable to its versatility and capacity to integrate this knowledge. Short article regarding the cyclists' airbag, developed by TNO.

The development of advanced driver assistance technology continues to proceed rapidly. Cooperative systems based on wireless communication are a specific form of advanced driver assistance that is currently evolving rapidly. A drawback in the development of such systems is that options for large scale field-testing and -development of these automated systems are limited. Traffic simulation however offers widespread options for testing. In this paper the effects of cooperative driving using cooperative adaptive cruise control (CACC) to influence congestion shockwaves are evaluated on a part of the Amsterdam freeway network. The effects of congestion shockwaves on a network scale can be different to uniform freeway sections due to interaction between varying traffic flows. The application of CACC to mitigate the negative effects of shockwaves on a network level are simulated and analysed in this research for varying levels of CACC penetration. The results are analysed on both a quantitative as well as qualitative level and give a deeper understanding into the possibilities of the mass application of CACC systems. © 2011 IEEE.

Energy recuperation in fully electric vehicles is mainly limited by the requirement to preserve vehicle stability but it is also dependent on the brake system design and the ability of the control system. The boundaries of vehicle stability are difficult to assess, and must be approached with care, e.g. when maximizing the regenerative braking during cornering on slippery surfaces. Model based predictive control (MPC) is used in this paper to account for the main vehicle dynamics behaviour and to optimize the regenerative braking. A state estimator is also used to estimate the states fed back to the controller and other vehicle and road parameters used in the MPC problem formulation. The state estimation is capable of predicting road friction and accurately provides the current driving condition to the controller also under challenging braking conditions such as mu-split braking. The MPC controller shows a clear compromise between vehicle stability and the energy recuperation potential. The developed MPC concept together with the state estimator is a versatile method that can adapt to various brake designs and tuning objectives. The proposed setup is a good starting point for implementation on an actual vehicle.

New driver support systems require knowledge of the vehicle position with great accuracy and reliability. Satellite navigation (GNSS) is generally insufficiently accurate for positioning and as an alternative to using a ground station, combinations with high quality motion sensors are used in so-called Inertial Navigation Systems. However the system specifications and related cost are not suitable for Automotive applications. In this article a Vehicle model based concept is presented in a state estimator setup that will use signals that are available on modern vehicles. An extension of a commonly used Bicycle representation of the vehicle is applied with an automated tuning for signal disturbances. For coping with different update frequencies from GNSS and motion sensors a Bezier extrapolation is used. The resulting Adaptive Kalman Filter approach is compared to recorded signals from driving tests with an instrumented vehicle. The comparison shows that with the new setup a clear improvement is achieved for the vehicle motions compared to more commonly used Kalman filtering. This verifies that sensor disturbances can better be compensated with the presented concept, and also better results for positioning can be expected. © 2011 IEEE.

In this study, human kinematic response resulting from various pre-crash braking scenarios is quantified. The underlying question is what kind of effect do pre-crash braking systems have on the driver or the front seat passenger.

This paper describes the results of vehicle-to-vehicle (V2V) and infrastructure-to-vehicle (I2V) experiments implementing cooperative maneuvering for three different vehicles driving automatically. The cars used were cybercars from the Institut National de Recherche en Informatique et Automatique (INRIA), (France), which are fully automated road vehicles, and two mass-produced carsone a Smart Fortwo car from TNO (Netherlands) equipped with additional actuators and sensors and the other a convertible Citron C3 from IAI (Spain) that uses sensorial information to manage the actuators. The cars communicate by a wireless mesh network over Wi-Fi using the optimized link state routing (OLSR) ad-hoc protocol. The entire communication task is embedded in a small MIPS Linux Box (4G System Cube) that is transparent for the cars. A standard framework was defined with the parameters needed to perform adaptive cruise control (ACC) and intersection maneuvers among the cars, as well as emergency stops via a signal sent by the infrastructure. The experiments were carried out in La Rochelle (France) during the final demonstration of the European Union (EU) Cybercars-2 Project. © 2010 IEEE.

This paper describes the design, implementation and results of a novel probabilistic collision warning system. To obtain reliable results for risk estimation, preprocessing sensor data is essential. The work described herein presents all the necessary preprocessing steps such as filtering, sensor fusion and target tracking. Risk estimation can be much more accurate if the behavior of road users is modeled correctly. Therefore, behavior models for individual road user (pedestrians, cyclists and drivers) are described in terms of probability density functions. These functions are based on statistical properties obtained from literature and experimental results. Preliminary results of road tests are presented in a scenario that includes a pedestrian and two cyclists. The results show that the approach successfully handles the unpredictable behavior of vulnerable road users and vehicles in both forward and sideward direction.

In this paper, a collision warning application is described. The collision warning application is in particular useful when the driver’s view is blocked due to a large vehicle. The risk estimation algorithm, which is originally designed and validated in scenarios with vulnerable road users, is here applied in a non-line-of-sight scenario with vehicles. In this experimental setup wireless communication is used as sensor instead to the traditional sensor systems, e.g. radar, lidar and/or vision. The applicability of the collision warning algorithm is shown in experiments with two Toyota Prius vehicles and a large truck.

On one hand automotive manufacturers are trying to reduce product development times, while on the other hand they are aiming to bring more products to the market. Since safely and reliability must always be guaranteed, they use CAE to achieve this. For calculating road loads accurately, the tire and road model are key components of the CAE model. TNO has developed the MF-Swift tire model, which is a Magic Formula based rigid ring model. In combination with its enveloping model, MF-Swift can be used to simulate the tire dynamic response to arbitrary road unevenness. MF-Swift is aimed to be an all-encompassing tire model that can be used for handling, ride comfort and durability applications. Since it is based on Pacejka's Magic Formula, its application for handling events is well-known. Recently the OpenCRG road format has been released which makes it possible to describe large pieces of digitized 3D road surfaces in a uniform and efficient way. The objective of this paper is to demonstrate that the combination of the MF-Swift tire model and the OpenCRG road format can be used to accurately simulate road loads for typical durability events, showing that the rigid ring model concept is an alternative to much more complex flexible ring models, while maintaining the advantages of using Pacejka's Magic Formula for describing the slip forces. © 2011 SAE International.

Deutscher Erfindergeist sorgte dafür, dass der Airbag im Auto zur Serienausstattung zählt. Allein in den USA soll er bislang mehr als 25.700 Menschen das Leben gerettet haben. Jetzt steht die Entwicklung einer neuen Airbag-Generation in der entscheidenden Phase - ohne deutsche Beteiligung: Niederländische und schwedische lngenieure entwickeln Sensoren und Luftkissen, die Radfahrer und Fußgänger schützen sollen.

This paper presents the results of the Davit-Launched Lifeboat Project (DLLBP). The project was initiated by the Norwegian Oil Industry Association (OLF) in December 2009, and was executed as a joint effort between OLF and the Norwegian Shipowners' Association (NSA). The project is a continuation of NSA LAP (Life-saving Appliances Project) and lessons learned in OLF Free Fall Lifeboat Project. The project was organised in six Work Packages (WPs) and was completed in June 2011. The studies in the project covered the following phases during lifeboat evacuation; (1) lifeboat lowering, (2) water entry, (3) release of wire falls and (4) sail-away. Findings and recommendations related to each of the four phases are presented in this paper. The members of the Norwegian Lifeboat Network, consisting of representatives from authorities, unions, suppliers, OLF and NSA, were informed during the course of the project.

This report documents research started in 2002 that identified the potential need for explicit neck injury criteria and tolerances for certification of side-facing seats in aircraft. Laboratory sled tests with full-body postmortem human subjects proved that there is a substantial risk for serious (potentially lethal) neck injuries under realistic crash load conditions, simulated by the 16-g, 180-ms crash pulse designated by Title 14 Code of Federal Regulations 25.562. Further research of the loading and injury mechanism were conducted using numerical simulations of advanced rigid-body models of the EuroSID-2 (ES-2) anthropomorphic sideimpact crash dummy, which originated from automotive crash safety research. This research led to proposing an ES-2 upperneck tension force injury assessment reference value of 2100 Newton. Injuries to other body structures were documented and recommended for future research as they compromise the escape capabilities of the aircraft occupants, e.g., unconsciousness by head angular acceleration, immobilization by fractures to the upper leg, multiple rib fractures from belt loading, or carotid artery tears, which can lead to a fatal stroke months after the accident. The ES-2 was determined to have sufficient biofidelity for use in aircraft side-facing seat certification requirements. Issues with respect to the ES-2’s neck durability and shoulder-belt interaction are noted.