Remote-controlled edge-node considerations

Original equipment manufacturers (OEMs) and designers investigating remote-controlled edge technology must consider latency, functional safety, cybersecurity and cost.

Latency is a significant design challenge. Data from the edge must travel upstream, where decisions are made from the edge for processing, then back downstream to the edge for implementation, which adds latency delays to the real-time control loops. Figure 6 shows this process for sensing and controlling a load. Traditional edge nodes only require Step No. 2 and Step No. 5, while remote-controlled edge solutions implement features such as intelligent actions or autonomous polling to reduce delays. Intelligent actions allow the bridge device to automatically transmit sensor data without initial prompting by the commander ECU, eliminating Step No. 1. Autonomous polling enables the bridge device to automatically sample from a sensor and store the reading to a buffer. This allows Step No. 2 to occur during other steps, which can help further reduce latency.

Functional safety concerns may arise because there is no longer local real-time control. Edge applications with strict requirements such as tight latency requirements from Fault Tolerant Time Interval specifications may struggle with upstream communications delays. As a newer technology, first-generation remote-controlled edge devices may not meet Automotive Safety Integrity Level requirements, or may need additional measures to achieve functional safety at a system level.

Cybersecurity risks increase as vehicles become more software-dependent. Without proper security measures, hackers can access the vehicle network and control features throughout the vehicle, which can result in theft and safety risks. Cybersecurity is more difficult to implement on remote-controlled edge nodes since there is no MCU to manage security locally, so it is important for OEMs to select solutions that meet their cybersecurity needs.

Cost considerations must balance hardware and software expenses. Replacing the low-level MCUs currently used in traditional edge nodes with remote-controlled edge-node devices is potentially more expensive. It is important to remember, however, that even if hardware costs increase, there are still significant savings in software development and management costs.

Remote-controlled edge enables automakers to manage more software internally, requiring OEMs to evaluate the trade-offs.