Document ID: chunk:federal_register_of_legislation:F2018L01515:body:0:p31
Version: federal_register_of_legislation:F2018L01515
Segment Type: other
Provision Reference: 
Character Range: 88737–91813

compatible with the operating characteristics of the steering system installed on the vehicle. This shall be confirmed by the vehicle manufacturer at the time of type approval.

Annex 6
       Special requirements to be applied to the safety aspects of complex electronic vehicle control systems
1. General
 This annex defines the special requirements for documentation, fault strategy and verification with respect to the safety aspects of Complex Electronic Vehicle Control Systems (paragraph 2.3. below) as far as this Regulation is concerned.
 This annex may also be called, by special paragraphs in this Regulation, for safety related functions which are controlled by electronic system(s).
 This annex does not specify the performance criteria for "The System" but covers the methodology applied to the design process and the information which shall be disclosed to the Technical Service, for type approval purposes.
 This information shall show that "The System" respects, under normal and fault conditions, all the appropriate performance requirements specified elsewhere in this Regulation.
2. Definitions
 For the purposes of this annex,
2.1. "Safety concept" is a description of the measures designed into the system, for example within the electronic units, so as to address system integrity and thereby ensure safe operation even in the event of an electrical failure. The possibility of a fall-back to partial operation or even to a back-up system for vital vehicle functions may be a part of the safety concept.
2.2. "Electronic control system" means a combination of units, designed to co-operate in the production of the stated vehicle control function by electronic data processing. Such systems, often controlled by software, are built from discrete functional components such as sensors, electronic control units and actuators and connected by transmission links. They may include mechanical, electro-pneumatic or electro-hydraulic elements. "The System", referred to herein, is the one for which type approval is being sought.
2.3. "Complex electronic vehicle control systems" are those electronic control systems which are subject to a hierarchy of control in which a controlled function may be over-ridden by a higher level electronic control system/function. A function which is over-ridden becomes part of the complex system.
2.4. "Higher-Level control" systems/functions are those which employ additional processing and/or sensing provisions to modify vehicle behaviour by commanding variations in the normal function(s) of the vehicle control system. This allows complex systems to automatically change their objectives with a priority which depends on the sensed circumstances.
2.5. "Units" are the smallest divisions of system components which will be considered in this annex, since these combinations of components will be treated as single entities for purposes of identification, analysis or replacement.
2.6. "Transmission links" are the means used for inter-connecting distributed units for the purpose of conveying signals, operating data