A Study on TSC (Technical Safety Concept) Design and Verification in EMB (Brake by Wire) Systems

Abstract

<div class="section abstract"><div class="htmlview paragraph">The Electro-Mechanical Brake (EMB) system is a dry-type Brake-by-Wire technology that eliminates hydraulic components and directly controls friction braking using electrical actuators at each wheel. The EMB architecture consists of a Main Center Control Unit, a redundant Backup Center Control Unit, and four Wheel Control Units communicating via CAN FD.</div><div class="htmlview paragraph">Due to its direct involvement in vehicle braking, compliance with ISO 26262 functional safety requirements is critical. As system complexity increases, potential risks such as hardware failures and communication faults must be systematically addressed.</div><div class="htmlview paragraph">The proposed TSC was developed according to ISO 26262, covering the concept phase (Part 3), system-level development (Part 4), and software implementation (Part 6).</div><div class="htmlview paragraph">Safety goals and Functional Safety Requirements derived from HARA are used to guide system architecture design and TSC development. Key design principles include modularity, redundancy, fault detection, and fail-safe operation.</div><div class="htmlview paragraph">Verification is conducted at both system and vehicle levels using ECU-in-the-Loop Simulation (EILS), Hardware-in-the-Loop Simulation (HILS), and real-vehicle tests. Fault scenarios, including Main Center Control Unit failures and CAN communication losses, are injected using a custom LabVIEW-based fault injection tool. The study evaluates Fault Tolerant Time Interval (FTTI) settings, error handling mechanisms, and control handover strategies under fault conditions.</div><div class="htmlview paragraph">The results show that redundancy and localized communication enable stable operation and smooth control transfer within the FTTI window without noticeable impact on braking performance or driver awareness. This study demonstrates the robustness of the proposed EMB architecture. Future work will focus on prognostics and maintenance strategies to support safe deployment in autonomous and electric vehicles. ^[<span class="xref">¹</span>, <span class="xref">²</span>, <span class="xref">³</span>, <span class="xref">⁴</span>, <span class="xref">⁵</span>, <span class="xref">⁶</span>, <span class="xref">⁷</span>, <span class="xref">⁸</span>, <span class="xref">⁹</span>, <span class="xref">¹⁰</span>^]</div></div>