Dual CPU Brake Control for Manned Unmanned Utility Vehicles
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Dual-mode vehicles require a brake system that can safely operate in both manned and unmanned modes, ensuring safe braking in autonomous mode while preventing unintended brake engagement during manned operation to maintain operator control.
Innovation Solution
A brake control system incorporating a hydraulically operated brake, a manually operated brake circuit, and an electro-hydraulic (E-H) brake circuit with redundant central processing units (CPUs) and solenoid-operated valves, where the E-H system is isolated during manned operation to prevent accidental brake engagement, but can engage the brakes in case of a single point failure during unmanned operation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a single CPU controls the E-H braking system in autonomous mode, then the vehicle can be brought to a halt safely in case of failure, but in manned mode the same single CPU could accidentally engage brakes causing loss of control
Solution Approach 1:
The control system is segmented into two independent CPU units (CPU1 and CPU2), each capable of independently controlling the braking system. This segmentation allows the system to provide single-point-failure protection in autonomous mode while preventing accidental brake engagement in manned mode through dual-confirmation requirements.
Solution Approach 2:
The system dynamically changes its control logic based on the operational mode (manned vs. autonomous). In autonomous mode, either CPU1 or CPU2 can independently activate brakes for single-point-failure protection. In manned mode, both CPUs must simultaneously confirm brake activation to prevent accidental engagement, creating adaptive safety behavior.
2Ease of operation
If the E-H brake circuit is isolated during manned operation, then operator control is maintained, but the system complexity increases with multiple valves and CPUs
Solution Approach 1:
The E-H brake circuit with multiple solenoid valves (inlet valve, first brake valve, second brake valve) and dual CPUs serves multiple functions: it provides single-point-failure protection in autonomous mode, prevents accidental brake engagement in manned mode, and maintains operator control. This multi-functional design justifies the increased complexity by delivering multiple safety benefits simultaneously.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
Ensures safe vehicle halting in autonomous mode while preventing sudden brake engagement that could lose operator control during manned operation, thereby ensuring safety and control in both operational modes.
Implementation Method 1
a solenoid operated inlet valve having an outlet and having an inlet connected to the pump
Implementation Method 2
a first solenoid operated brake valve having an outlet connected to the brake and having an inlet connected to the outlet of the inlet valve, and a second solenoid operated brake valve having an outlet connected to the brake
Implementation Method 3
an accumulator connected to the outlet of the inlet valve
Implementation Method 4
a pump; a solenoid operated inlet valve having an outlet and having an inlet connected to the pump
Data Source
AI summary
A brake control system is provided for a utility vehicle having manned and unmanned operational modes. The brake control system includes a hydraulically operated brake. A manually operated brake circuit and an electro-hydraulic (E-H) brake circuit are connected to the brake. The E-H brake circuit includes a pump, a solenoid operated inlet valve, an accumulator, and first and second solenoid operated brake valve connected between the brake and the inlet valve. A first CPU is operatively connected to the inlet valve and to the first brake valve. A second CPU is operatively connected to the inlet valve and to the second brake valve. An accumulator pressure sensor senses the accumulator pressure. A brake pressure sensor senses brake pressure. The first and second CPUs control the inlet valve and the brake valves as a function of the sensed accumulator pressure and brake pressure.