Electric Motor Fallback Braking for Brake-By-Wire Safety
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Brake-by-wire systems in electrically drivable motor vehicles require additional fallback levels to ensure safety in case of electronic failure, which increase weight, installation space, and cost, and existing solutions are not sufficiently reliable.
Innovation Solution
A safety system comprising a primary, secondary, and tertiary braking system with a monitoring device, detection and evaluation units to recognize and assess deceleration potential, and a control unit to manage vehicle operation based on safety criteria, ensuring reliable braking even in the event of system failures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If additional fallback levels are added to brake-by-wire systems to ensure safety, then reliability is improved, but weight increases
Solution Approach 1:
The patent combines the fallback braking function with the existing electric motor that provides propulsion. The electric motor is controlled to provide deceleration forces during normal operation and can serve as the fallback braking mechanism when the primary braking system fails, eliminating the need for separate fallback braking components.
Solution Approach 2:
The electric motor performs multiple functions: it provides propulsion during acceleration, enables regenerative braking during deceleration, and serves as the fallback braking mechanism when the primary braking system fails. This multi-functionality reduces the need for dedicated fallback braking components.
2Reliability
If additional fallback levels are added to brake-by-wire systems to ensure safety, then reliability is improved, but installation space increases
Solution Approach 1:
The patent combines the fallback braking function with the existing electric motor that provides propulsion. The electric motor is controlled to provide deceleration forces during normal operation and can serve as the fallback braking mechanism when the primary braking system fails, eliminating the need for separate fallback braking components.
3Reliability
If additional fallback levels are added to brake-by-wire systems to ensure safety, then reliability is improved, but cost increases
Solution Approach 1:
The electric motor performs multiple functions: it provides propulsion during acceleration, enables regenerative braking during deceleration, and serves as the fallback braking mechanism when the primary braking system fails. This multi-functionality reduces the need for dedicated fallback braking components.
4Device complexity
If the tertiary braking system's deceleration potential is insufficient, then device complexity is reduced, but reliability deteriorates
Solution Approach 1:
The control unit continuously monitors the operational status of the primary and secondary braking systems and the actual deceleration performance of the tertiary braking system. Based on this feedback, the control unit adjusts the control parameters of the tertiary braking system to ensure that the required deceleration potential is always achieved, even when the system is operating in fallback mode.
Data Source
AI summary
A safety system for an electrically drivable motor vehicle includes a primary braking system, a secondary braking system, and a tertiary braking system. The system includes a monitoring device configured to detect an operating error in the primary and/or secondary braking systems, a detection unit configured to acquire motor vehicle data, and an evaluation unit configured to assess an achievable deceleration potential of the tertiary braking system using the motor vehicle data. A comparison unit compares the evaluated deceleration potential to at least one defined safety criterion, and a control unit controls the motor vehicle based on the detection of an operating error and/or the comparison result. Also described are methods for operating the safety system, including recognizing an operating error, acquiring motor vehicle data, evaluating the deceleration potential, comparing the deceleration potential to a safety criterion, and controlling the motor vehicle based on these steps.