Electronic Throttle Control for Vehicle Speed Limiting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Recreational vehicles face challenges in controlling engine power to limit maximum speed and implement cruise control effectively, especially due to variations in load and the lack of brakes on personal watercraft, leading to inefficient performance and rough engine operation.
Innovation Solution
A vehicle control system using an electronic control unit (ECU) that adjusts the throttle valve opening based on both driver input and vehicle speed, ensuring the vehicle does not exceed a predetermined maximum speed, and incorporates a method for cruise control that can be engaged and disengaged without brakes, by sensing throttle operator position and vehicle speed, and adjusting the throttle valve actuator accordingly.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If the ECU controls engine power by limiting ignition and fuel injection when maximum speed is reached, then the maximum speed is limited, but the engine operation becomes rough and undesirable
Solution Approach 1:
The system proactively limits the throttle valve opening before the engine reaches maximum speed by using the ECU to control the throttle valve actuator. This prevents the engine from entering a rough operating state by restricting air intake in advance, rather than attempting to correct rough operation after it occurs through ignition/fuel injection control.
Solution Approach 2:
The patent replaces the traditional mechanical throttle cable connection with an electronic throttle control system. The ECU sends electronic signals to an electric throttle valve actuator, which precisely controls the throttle valve opening. This substitution enables smooth, continuous adjustment of the throttle position without the rough transitions associated with mechanical cable systems.
2Speed
If the predetermined maximum engine speed is selected to ensure the vehicle does not exceed maximum speed under light load, then the maximum speed limit is achieved, but the vehicle performance is reduced when load is increased
Solution Approach 1:
The system dynamically adjusts the maximum speed limit based on real-time vehicle conditions. The ECU continuously monitors vehicle load, speed, and operating parameters, and adjusts the throttle valve opening accordingly. This allows the vehicle to achieve different effective speed limits under different load conditions, optimizing performance while maintaining safety and regulatory compliance.
Solution Approach 2:
The patent changes the control parameter from a fixed engine speed limit to a dynamic throttle valve opening control. By adjusting the throttle position based on load conditions, the system achieves variable effective speed limits that adapt to changing vehicle requirements, rather than being constrained by a single fixed engine speed threshold.
3Speed
If a mechanical transmission is used to reduce speed and change rotation direction for reverse operation, then reverse direction control is achieved, but the transmission becomes complex and weight is added
Solution Approach 1:
The patent replaces complex mechanical transmission systems with electronic control. The ECU controls the throttle valve actuator to adjust engine power output, and works with an electric motor or electronically controlled propulsion system to achieve reverse operation. This substitution eliminates the need for complex mechanical gear trains and direction-changing mechanisms.
Solution Approach 2:
The electronic control system serves multiple functions: it controls forward speed, reverse speed, acceleration, and deceleration through a single integrated ECU and throttle actuator system. This multi-functional approach replaces what would traditionally require separate mechanical systems for each function, simplifying the overall vehicle architecture.
Data Source
AI summary
A vehicle has a straddle seat, a handlebar, an engine, an electronic control unit (ECU), a throttle valve, a throttle valve actuator, and a throttle operator. A throttle operator position sensor senses a throttle operator position. A vehicle speed sensor senses a vehicle speed. The ECU sends a control signal to the throttle valve actuator based on the throttle operator position and the vehicle speed. The throttle valve actuator adjusts the opening of the throttle valve in response to the control signal. If the vehicle speed is lower than a predetermined maximum vehicle speed, the throttle valve actuator adjusts the opening of the throttle valve based on the throttle operator position signal. If the vehicle speed is higher than the predetermined maximum vehicle speed, the throttle valve actuator reduces the degree of opening of the throttle valve. A method of controlling an engine is also disclosed.