Shared state, independent rendering approach to deliver a seamless user experience across IVI and Instrument Cluster displays

The global automotive Human Machine Interface (HMI) market is projected to reach nearly $303 billion by 2023, with a CAGR of 13.8% during 2018-2023, according to P&S Market Research. The increased demand for Automotive HMI is mainly being driven by rising in-vehicle connectivity, increasing sales of premium cars, and growing demand for enhanced safety features.
In the already saturated automobile market, it very important to exceed customer expectations with in-vehicle devices or applications in order to stand out. User satisfaction is not only influenced by usability factors but also by user experience (UX). The Automotive Industry requires in-car HMI to appear and act as a single user-experience. This requirement must hold true for numerous combinations of the underlying architectures and technologies: single or distributed SoC-based platforms, real-time Operating System (OS)-based Instrument Clusters, GENIVI Linux-based or Android-based Infotainment Systems, and more.
A holistic digital cockpit HMI with seamless user experience across IVI and Instrument Cluster displays can be implemented using different approaches such as:
•  Display Sharing
•  GPU Sharing (Virtualization) 
•  Surface Sharing
•  API Remoting
•  Shared State, Independent Rendering
In this blog post, I will discuss how using the shared state, independent rendering approach, a multi-domain system performs cross-domain HMI/services data sharing and local HMI rendering within each domain. Shared state independent rendering approach suggests self-contained graphics content rendering for each domain and a cross-domain data sharing service for HMI state and services data synchronization between domains.

Why Shared State, Independent Rendering approach?
The holistic perception of the HMI is achieved by ensuring that graphics data and rules for HMI design and functionality are aligned beforehand, on the independent rendering devices.  Synchronized software updates should be applied to ensure this relationship is intact if graphics are updated. This approach allows development of deeply-integrated functionally-rich UIs with complex screen animations and high degree of user interactivity.

Advantages to the Shared State, Independent Rendering approach are:
  Low inter-domain data channel bandwidth usage
  Applicability to mid/low performant SoC
  Operating System - agnostic approach

Shared State, Independent Rendering – A sample use case

A clear example of Share State, Independent Rendering is in navigation application data sharing between the IVI and Instrument Cluster. To prove the shared state independent rendering approach, the prototype of the data sharing service was implemented. The setup was built with GENIVI Linux for IC and Android for IVI. The HMI was implemented using Android native HMI on IVI system, and with Qt/HCAT-based HMI on Linux Cluster. This service provides functionality for sharing variable data types/structures between domains by using mechanisms of data registration, subscription and notifications. It included server part and client libraries for Linux and Android platforms.

The results proved that with this approach, we were able to develop distributed HMIs and to provide synchronized UX for the following scenarios:
-  IVI navigation content propagation to the Cluster Display
-  IVI and Cluster Animation synchronization
-  IVI content switching in accordance with Cluster Application State
To understand more about the Shared state approach, attend the upcoming Genivi Technical Summit in Bangalore, India that takes place on October 10-11, 2018. At this event, HARMAN will be showcasing its leading UI advancements through the HARMAN Automated UI Development Suite. Sergey Klevitskiy, HARMAN Principal Software Engineer will be presenting several HMI Use Cases at the event including:
•  Graphics Project & Distributed HMI Readout - Shared State Approach, Oct. 10th, 11:00 - 11:45 
•  Graphics Sharing & Distributed HMI Case Studies - Harman Android/QNX system PoC, Oct.10th, 14:00 - 15:30
•  Graphics Sharing & Distributed HMI Working Session, Oct. 11th, 9:30 - 12:30
Please take this opportunity to connect with our team and gain exposure to cutting-edge automotive advancements. Register on behalf of HARMAN today and use our FREE REGISTRATION CODE for the event! The HARMAN Registration Code is GVIP. Register Now
We look forward to seeing you there!