Karsten Lemmer

Generating high precision maps for advanced guidance support

Modern driver assistance systems increasingly support safer and more fuel-efficient driving. To fulfill these tasks information about the vehicle environment is essential. Besides extracting this information from sensors to perceive the environment, it is also possible to use stored static data. These models allow a reliable and fast access to the environmental data without the typical problems faced with the recognition by sensors, like noise or glitches. Nowadays street maps produced for navigation purposes reach a precision of several meters. To support the driver during manoeuvres however a precision one magnitude better is necessary. Positioning technology has steadily improved over the years and will further improve in the near future. Alongside this development it can be expected, that more precise digital maps will gain more importance. In this paper a method is presented to create these maps mainly automatically. The primary goal for this method is to achieve the best precision possible investing a very small effort. Data is recorded using a test vehicle equipped with a navigation system featuring high precision DGPS and inertial sensors. Lateral deviations are compensated by using a image processing lane-detection sensor. Several measurement iterations are made and merged into a digital map of the street using statistical methods. In order to show the suitability of the generated map for all kinds of ADAS, a test track was surveyed and the digital map was used for automatic guidance of another test vehicle. It could be shown that the map generation algorithm is generally able to produce high precision maps even in challenging environments, however ADAS demanding precise lateral and longitudinal position information can only rely on digital maps and GNSS in environments with little or no obstruction to the sky.

Supporting qualification: Safety standard compliant process planning and monitoring

Functional safety of embedded systems has become an integral part in automotive engineering activities due to the forthcoming safety standard ISO 26262. One main challenge is to perform development activities compliant to the standard and provide the respective documentation. Traceability between requirements from a standard, as well as project-specific process and product artifacts throughout the entire development cycle allows compliance assessment to support qualification. This paper proposes a methodology to plan and monitor the safety development process. Using a formalized requirements library of the ISO 26262 as well as a system description and its safety integrity level, a standard compliant process model is derived describing all necessary steps in the development process. Based on this process model, the methodology allows monitoring process activities and their degree of implementation, based on standard compliant confirmation measures. The main benefit is the reduced effort in preparing qualification or certification of a new safety-critical product. The development of an Adaptive Cruise Control system is sketched as an example application to illustrate the proposed proceeding.

Starting Model-Based Testing Based on Existing Test Cases Used for Model Creation

Model-based testing has a significant impact on test quality and test effort. However, many industrial projects still rely on the traditional testing methods. The biggest concerns against model-based testing are the need of formal knowledge and high initial costs for introducing the formal model. In this paper we show how it is possible to introduce model-based testing to a large scale industrial project by using the existing test cases as a basis for the model creation, thus effectively reducing concerns and efforts introducing the model-based testing approach. Additionally the created model can be used to simulate the reference behavior in an early development stage, resulting in a comprehensive prototype. The used context is a project in the railway industry domain, the European Train Control System, in which a lot of effort has been spent with the generation of high quality test cases.

Windows of Driver Gaze Data: How Early and How Much for Robust Predictions of Driver Intent?

Previous work has demonstrated that distinct gaze patterns precede certain driving manoeuvres [1,2] and that they can be used to build an artificial neural network model which predicts a driver’s intended manoeuvres [3,4]. This study seeks to move closer towards the goal of using gaze data in Advanced Driver Assistance Systems (ADAS) so that they can correctly infer the intentions of the driver from what is implied by the available incoming data. Drivers’ gaze behaviour was measured in a dynamic driving simulator. The amount of gaze data required to make predictions that manoeuvres will occur and the reliablity of these predictions at increasing pre-manoeuvre times were investigated by using various sized windows of gaze data. The relative difficulty of predicting different manoeuvres and the accuracy of the models at different pre-manoeuvre times are discussed.

Inverse Model Based Testing -- Generating Behavior Models from Abstract Test Cases

test cases contain a huge amount of domain specific knowledge of experts. Engineers may not use this knowledge only for validation purposes, e.g., applying test cases to software and hardware units, it can be also a starting point for modeling the product prototypically. This paper addresses the issue of generating a functional behavior model from abstract test cases. The test cases belong to the conformity and interoperability test standard for train-borne control units of the European Train Control System (ETCS). The contribution illustrates the approach and its advantages.

PEGASUS—First Steps for the Safe Introduction of Automated Driving

PEGASUS (Project for the Establishment of Generally Accepted Quality Criteria, Tools and Methods as well as Scenarios and Situations for the Release of Highly Automated Driving Functions) is a joint project funded by the German Federal Ministry for Economic Affairs and Energy (BMWi) which seeks to close the gaps in the testing and release of automated vehicles (see Fig. 1) and supports the rapid transfer of existing functions and prototypes into series production (Fig. 2). PEGASUS intends to answer these central questions. What is the minimum performance level for an automated vehicle? How do human beings perform (as a reference value)? What can and must automation deliver (and what not)? How can it be demonstrated that the automated vehicle performs reliably? Open image in new window Fig. 1 Current state of development of highly automated driving Open image in new window Fig. 2 Advancement through PEGASUS

Modeling driver behavior at roundabouts: Results from a field study

Advanced Driving Assistance Systems could improve driving safety and comfort by supporting drivers in their driving task. To realize intelligent assistance, driver behavior prediction and recognition is an important challenge. Therefore, the aim of this study is to develop a method to predict whether a vehicle, having entered a roundabout, will choose an upcoming exit or stay within the roundabout. A field study has been conducted to collect driving behavior data for analyzing and modeling human driver behavior in interaction with roundabouts. Support vector machines proved to be a robust and efficient classification method for the roundabout leaving/ staying pattern recognition problem. From the experimental results the vehicles position can be estimated, for which the prediction becomes reliable. The steering wheel angle and angle velocity also proved to be able to provide sufficient information to predict the driver behavior at the investigated roundabouts.

Elektrik/Elektronik/Software

Steigende Anforderungen hinsichtlich Sicherheit, Umweltschutz und Komfort fuhrten in den vergangenen Jahren zu einem starken Anstieg der Funktionen im Fahrzeug. Wesentliche Treiber dafur waren die gestiegenen Komfortanspruche, die Vernetzung der Fahrzeuge aber auch ganz wesentlich verscharfte Abgas- und Sicherheitsbestimmungen. So kamen in den letzten Jahren komplexe Infotainment und Assistenzsysteme hinzu, die nur durch ein Zusammenwirken vieler Steuergerate realisiert werden konnten. Deren intuitive Bedienung sowie Personalisierung der Funktionen erforderte eine systemubergreifende Mensch-Maschine-Schnittstelle. Durch die massiv gestiegene Anzahl an elektrischen Verbrauchern nahm auch der Energiebedarf deutlich zu, sodass uber elektronische Energiemanagementsysteme ein optimierter Energiehaushalt sichergestellt werden musste.

Form Follows Vision User-Centred Interface Design for Rail Traffic Controllers´ Workplaces

Abstract In our Rail Human Factors approach, we define the human as the starting point for our interdisciplinary research on the design of human-machine interfaces in railway systems. One key focus of this approach is on the future workplace of the rail traffic controller. In this paper, a collaboration project between human factors scientists and trained rail traffic controllers is presented. Based on the methodological background of usability engineering, an innovative interpretation of the user interface of the German electronic interlocking system (ESTW) was developed. First prototypical propositions for the design of a future interlocking system were generated in an iterative process of design and feedback phases. Here, we made use of the advantages of the domain expertise of the usability experts as well as the rail traffic controllers. The resulting design is characterized by a decluttered central display / control panel on a single monitor.

Das atomare Element als Meta-Modell zur tabellarischen Verhaltensbeschreibung von Echtzeitsystemen

Testen komplexer Funktionen sicherheitsgerichteter Echtzeitsysteme ist sehr aufwandig und kompliziert. In dem Beitrag wird eine tabellarische Verhaltensbeschreibung vorgestellt, die auf Basis des atomaren Elements, das Systemverhalten transparenter und besser verstandlich machen soll. Mit Hilfe des atomaren Elements als Meta-Modell kann das Verhalten nicht nur eindeutig, konsistent und genau beschrieben werden, vielmehr kann das Verhalten hierarchisch strukturiert,verfeinert und bzgl. verschiedener systemtechnischer Aspekte differenziert werden.