Redundant Power Rail Isolation for Autonomous Vehicle Emergency Stop

Solution Overview

Problem

Autonomously driven vehicles face catastrophic consequences due to critical electrical system failures, as they lack a driver to manage steering and braking systems, and existing redundant power distribution systems increase complexity and cost.

Innovation Solution

A power distribution system with adjustable vehicle switches, safety critical power rails, and diagnostic circuits that ensure safe autonomous operation by disconnecting faulty power rails and engaging redundant systems, utilizing a single charging system to maintain battery charge levels.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If fully redundant power distribution systems are provided, then safety and reliability are improved, but device complexity and cost increase significantly

Engineering Contradiction:

ImprovesafetyVSAvoidcomplexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The power distribution system is segmented into a general purpose power rail and a safety critical power rail, allowing independent monitoring and control of each rail. This segmentation enables the system to provide redundancy for safety-critical functions without fully duplicating the entire power distribution system, thereby improving safety while limiting the increase in complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A safety switch is introduced as an intermediary component between the general purpose power rail and the safety critical power rail. This safety switch can disconnect the safety critical rail from the general purpose rail when faults are detected, providing a simple yet effective mechanism to ensure safety without requiring complex redundant systems.

Inventive Principle:

Principle #24Intermediary (Mediator)

2Reliability

If fully redundant power distribution systems are provided, then safety and reliability are improved, but cost increases significantly

Engineering Contradiction:

ImprovesafetyVSAvoidcost

Core Design Contradiction:

ReliabilityVSEase of manufacture

Solution Approach 1:

The power distribution system is segmented into a general purpose power rail and a safety critical power rail, allowing independent monitoring and control of each rail. This segmentation enables the system to provide redundancy for safety-critical functions without fully duplicating the entire power distribution system, thereby improving safety while limiting the increase in complexity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

A safety switch is introduced as an intermediary component between the general purpose power rail and the safety critical power rail. This safety switch can disconnect the safety critical rail from the general purpose rail when faults are detected, providing a simple yet effective mechanism to ensure safety without requiring complex redundant systems.

Inventive Principle:

Principle #24Intermediary (Mediator)

3Difficulty of detecting and measuring

If diagnostic tests are performed continuously, then fault detection capability is improved, but energy consumption increases

Engineering Contradiction:

Improvefault detection capabilityVSAvoidenergy consumption

Core Design Contradiction:

Difficulty of detecting and measuringVSUse of energy by moving object

Solution Approach 1:

The diagnostic circuit performs voltage level checks periodically or event-triggered rather than continuously monitoring all parameters. The safety switch monitors voltage levels at different points in the power distribution system and only triggers disconnection when fault conditions are detected, reducing energy consumption while maintaining effective fault detection capability.

Inventive Principle:

Principle #19Periodic action

Data Source

PatentUS12157377B2Redundant vehicle power distribution system

Publication Date: 2024.12.03 ATIEVA INC(US)

AI summary

A power distribution system is provided that ensures that a car is able to operate safely in an autonomous mode. The system includes multiple power rails, including a pair of safety critical power rails. Associated with each safety critical power rail is a safety switch, vehicle sensors (e.g., vehicle location and obstacle sensors), vehicle actuators (e.g., braking and steering actuators) and an autonomous control unit. If a fault is detected during vehicle initialization or general operation, the safety switch which detected the fault opens and that particular power rail is decoupled from the general purpose power rail as well as the remaining safety critical power rail. The remaining safety critical power rail is then able to provide power to a sufficient number of sensors, actuators and controllers to allow the car to safely and autonomously complete an emergency stop on the side of the road.