Multimedia Unit for Electric Vehicles

Our Approach

Softeq helped the client create a multimedia unit based on two different generations of processors.

The customer planned to bring their products to the market in a short time frame, so they wanted to start testing the multimedia unit as soon as possible. We proposed a modular solution architecture, which would allow us to quickly adapt the multimedia unit should the customer decide to change their requirements based on the test results.

Choosing the Right Processor

We examined 10+ solutions available on the market and opted for the Snapdragon processor (Qualcomm) as a basis for the first generation units.

Through this process, we designed the current version of the device, which uses one of the latest NXP processors.

Display Interfaces

The multimedia unit supports multiple connectivity options to interface with a range of displays:

• Cluster display (dashboard information)
• Media display (music, climate control, navigation, radio, browser)
• Service display (vehicle documents)
• Head-up display (projecting critical driving information onto the windshield)
• Optional displays (in-car media streaming)

Connectivity

The solution supports multiple connectivity methods.

Automotive gateway:

• Automotive Ethernet
• LIN
• CAN

External connectivity:

• Wi-Fi
• LTE
• Bluetooth

Wired interface:

• Ethernet
• MOST

Cameras and Display Subsystems

The multimedia unit has four camera FPD-Link III and GMSL inputs and four FPD-Link III display inputs. For the display subsystem, we developed a custom universal adapter to support various types of LCD panels. The adapter receives the signal via FPD-Link lll from the multimedia unit, decodes it, and delivers it to the display. The adapter is also responsible for managing backlight, vibration feedback on the touch-screens, and additional buttons.

Safety

The multimedia unit is running on Android. In addition to the dashboard, it also displays media and service data. In the event of an error, it is possible that the Android operating system will crash.

To ensure that safety-critical data will be displayed at all times, we integrated SAFERTOS. It uses a watchdog to monitor Android performance and reliability. If Android fails or becomes unresponsive to a driver’s commands, SAFERTOS will reboot the Android OS and display safety-critical information like the speedometer, tachometer, gearbox, braking system status, etc.

Audio Noise Cancellation, Radio, Sound

The vehicle features a sound processing system that incorporates six microphones. Two microphones capture the driver's voice, while the other four capture extraneous noise like engine sounds and noise from the street.

Together with the client's team, Softeq developed algorithms that subtract the extraneous noise captured by the other four microphones from the driver's voice, allowing them to give clear verbal commands to the system.

The unit also supports connection to AM, FM, DAB, and DAB+ radio sources, features a high-end 4-chs audio amplifier, audio digital interface MOST, and analog aux outs. The advanced audio system is capable of delivering 5.1 sound.