Upcoming Trends in Body Control Module: The Industry Insider’s View

What are the major innovations that you have observed in an automobile in the recent times? The ones that come to the mind instantly are key-less entry, climate control air conditioning, infotainment system, automotive lighting systems, seat comfort solutions and a few more. Most of these new features are more or less connected to the body electronics. And Body Control Module (BCM) is at the center of it all.

Body Control Module can be seen as a unit or group of units that control three broad categories of features- interior and exterior lighting, security and comfort. BCM is among the most rapidly innovating automotive modules. Technologies like V2V and V2X connectivity are some of the key drivers of innovation that the automotive industry is witnessing with respect to the body electronics.

Other catalysts of such ongoing evolution in BCM is the consumer’s demand for driving comfort as well as the safety of drivers and passengers. The path of evolution that body control module is taking is being largely guided by such market demands.

We will examine this path of evolution and learn about the upcoming trends on various parameters such as vehicle architecture, in-vehicle networking, security, Functional Safety standards and more. Stay tuned!

Body Control Module Innovations in terms of Architecture

The next generation of the body control module is heavy on loads viz. exterior and interior lighting, seats, access control, HVAC and more. This gives rise to control and networking issues because the loads require faster as well as diverse communication networks.

Several BCM architectures are capable of managing such control. From a 3-tier BCM architecture to a centralized body electronics domain, OEMs have been deploying such variants. However, the trends show that a centralized BCM architecture is preferred over a distributed BCM.

A centralized BCM has all of the body functions and gateway mechanism integrated to one central module. Since different functions might require low, medium or high data transfer rate, a gamut of ECU communication protocols have to be integrated in the system. This implies that LIN, CAN and even Ethernet co-exist in a centralized gateway application.

A Typical Body Control Module Architecture

A few keywords that define the future of centralized BCM are:

· Zonal Gateway: Sensors and actuators are connected to the central BCM through zonal gateway. This gateway function enables different nodes to process data coming over protocols like LIN, CAN etc. As a result, legacy ECUs can co-exist in a system.

· Centralized computing: As mentioned above, centralized computing is all about consolidating all body electronics functions in one single platform. In addition to making the system less cluttered, it makes way for a more compact and secure platform.

Growth of Ethernet as an ECU Communication Protocol

Higher bandwidth requirement and increased frequency of software updates are some use-cases that CAN and LIN are unable to service with utmost efficiency. Ethernet as a proven communication protocol is now being increasingly used in the automotive domain. Although CAN and LIN have predominantly been the backbone of inter-ECU communication, Ethernet has made great strides through its presence in applications such as ADAS, V2X and automated driving technology.

Ethernet promises a data rate of up to 100 Mbps which is only going to increase in the future. Add to that, a host of protocols like TCP/IP and SOME/IP that are perfect for Ethernet, and in all likelihood, Ethernet is going to be the future network protocol of the automotive domain.

Thanks to the gateway functionality of BCM, it coexists with CAN and LIN. However, it has all the potential to be the de-facto ECU communication protocol in the near future. Big names like Broadcom, NXP, Microchip, Vector and Cadence have rapidly moved forward in development of automotive Ethernet and the supporting technology.

Innovations Aimed Towards Security

Cybersecurity becomes a pressing issue when software and communication are involved. Automobiles have been easy targets for hackers as they can cause huge damage once they take control of an automobile’s computer system.

Security and safety modules are being integrated to body control modules. Trends show that both software and hardware-based security modules are being deployed to save the BCM from cybersecurity attacks.

A few automotive features that are being used to ensure cybersecurity are:

· Seed and Key algorithm: This is a security algorithm used to gain access to an ECU that is protected from unauthorized access. The idea behind seed and key algorithm is that an ECU provides a seed, which needs to be transformed into a key with the help of a secret algorithm.

· SHA 256 hash algorithm: SHA 256 is a hashing algorithm that is frequently used in making the ECU communication encrypted.

· Hardware security module: This module lies inside the ECU’s main processor and provides protection from cybersecurity threats at the hardware level. A typical HSM comprises a hardware accelerator, random number generator and a separate RAM. Most modern Body Control Module have built-in HSM to ensure an extra layer of cybersecurity.

· Secure flash bootloader: Flash bootloader is an indispensable software component, especially in an era where updates are quite frequent. As the flash bootloader is capable of re-programming the automotive ECU, it can be utilized to gain unauthorized access to the body control module of a vehicle. Hence, to avoid such scenarios, the new-age BCM is relying on secure bootloaders where SHA-256, seed and key algorithms etc. are used to ensure security.

Functional Safety (ISO 26262)

ISO 26262 mandated Functional Safety is highly relevant for a body control module as many of its components are directly related to the safety of the driver and the passenger. Hence, this has become part of the evolution of BCM.

In a way, ISO 26262 is itself a trend that is transforming into a mandatory part of automotive software development lifecycle, and BCM is no exception. Let’s try to understand it with a simple example.

One of the safety goals of a central locking system is that the door is automatically locked as the vehicle crosses the speed of 10km/h. Failing to do so can make the door vulnerable to opening while the vehicle is in motion. Hundreds of such safety goals are identified while following ISO 26262 standard during the development of a body control module. As the BCM platforms continue to evolve, ISO 26262 standard will continue to guide such innovations.

Final Thoughts

Body Control Module is at the peak of innovation at an ideal time when consumers are more concerned about features and less about the cost of the vehicle.

In addition to the latest trends in automotive BCM discussed in this blog, there are a multitude of other fronts where BCM and other automotive systems are evolving. Some of them are AUTOSAR and Model Based Design & Development.

It will be interesting to witness the evolution of BCM and the plethora of safety and comfort features that are introduced during the course of this evolution.