The Qt application framework is widely used in automotive infotainment systems with a variety of operating system and hardware configurations. With digital instrument clusters becoming increasingly common in new models, there are significant synergies to be gained from using the same technologies for both the infotainment system and the cluster. To be able to do this, you need to choose technologies, such as Qt and QNX, that can easily address the requirements of both environments.
Qt is the leading cross-platform technology for the creation of applications and user interfaces for desktop, mobile, and embedded systems. Based on C++, the Qt framework provides fast native performance via a versatile and efficient API. It’s easy to create modern, hardware-accelerated user interfaces using Qt Quick user interface technology and its QML language. Qt comes with an integrated development environment (IDE) tailored for developing applications and embedded devices. Leveraging the QNX Neutrino Realtime OS to run Qt provides significant advantages for addressing the requirements of functional safety.
There is a strong trend in the automotive industry to create instrument clusters using digital graphics rather than traditional electromechanical and analog gauges. Unlike the first digital clusters in the 70s, which used 7-segment displays to indicate speed, today’s clusters typically show a digital representation of the analog speedometer along with an array of other information, such as RPM, navigation, vehicle information, and infotainment content. The benefits compared to analog gauges are obvious; for example, it is possible to adapt the displayed items according to the driver’s needs in different situations, or easily create regional variants, or adapt the style of the instrument cluster to the car model and user’s preferences.
A unified experience — for both developers and users
Traditionally, the speedometer and radio have been two very different systems, but today their development paths are converging. Convergence will drive the need for consistency as otherwise the user experience will be fragmented. To meet the needs of tomorrow’s vehicles, it is essential that the two screens are aware of each other and interoperate. It is also likely that, while these are converging, certain items will remain specific to each domain. Furthermore, the convergence will help accelerate time-to-market for car manufacturers by offering simplified system design and faster development cycles.
Qt, which is already widely used in state-of-the-art in-vehicle infotainment systems and many other complex systems, is an excellent technology to unify the creation of these converging systems. By leveraging the same versatile Qt framework and tools for both the cluster and the infotainment system, it is possible to achieve synergies in the engineering work as well as in the resulting application. With the rich graphics capabilities of Qt, creating attractive user interfaces for a unified experience across all screens of the vehicle cockpit becomes a reality.
Cluster demonstrator built with Qt 5.6.
Qt has been used very successfully in QNX-based automotive and general embedded systems for a long time. To show how well Qt 5.6 and our latest Qt based cluster demonstrator run on top of the QNX OS, which is pre-certified to ISO 26262 ASIL D, we brought them together on NXP’s widely used i.MX 6 processor. As the cluster HMI is made with Qt, it runs on any platform supported by Qt, including the QNX OS, without having to be rewritten.
The cluster demonstrator leverages Qt Quick for most of the cluster and Qt 3D for the car model. The application logic is written in C++ for maximal efficiency. By using the Qt Quick Compiler, the QML parts run as efficiently as if they too were written in C++, speeding up the startup time by removing the run-time compilation step.
The following video presents the cluster demonstrator running on the QNX OS and the QNX Screen windowing system:
The QNX OS for Safety has been certified to both IEC 61508 SIL 3 and ISO 26262 ASIL D, so it provides a smooth and straightforward path for addressing the functional safety certification of an automotive instrument cluster.
Qt 5.6 has been built for the QNX OS using the GCC toolchain provided by QNX Software Systems. The display of the cluster is a 12.3" HSXGA (1280×480) screen and the CPU is NXP’s i.MX 6 processor, which is well-suited to automotive instrument clusters.
Our research and development efforts continue with a goal to make it straightforward to build sophisticated digital instrument clusters with Qt. We believe that Qt is the best choice for building infotainment systems and clusters, but that it is particularly beneficial when used in both of these. Please contact us to discuss how Qt can be used in automotive, as well as in other industries, or to evaluate the latest Qt version on the QNX platform.
Visit qt.io for more information on Qt.
Tuukka Turunen leads R&D at The Qt Company. He holds a Master’s of Science in Engineering and a Licentiate of Technology from the University of Oulu, Finland. He has over 20 years of experience working in a variety of positions in the software industry, especially around connected embedded systems.