Brake-Linked Electric Shifting Control for Smoother Bicycle Gear Changes
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing shifting control devices for human-powered vehicles do not provide a comfortable riding experience, particularly during braking, as they fail to smoothly adjust the transmission ratio in response to user operations and travel conditions.
Innovation Solution
A shifting control device that controls the shifting device based on operations performed on an operating device, including braking, to adjust the transmission ratio, taking into account operation and travel information, ensuring a comfortable riding experience.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the shifting device is controlled to change transmission ratio during braking operation, then the riding comfort is improved, but the device complexity increases due to integration of shifting control with braking operation detection
Solution Approach 1:
The patent combines the shifting control function with the braking operation detection system. The operating device for braking is integrated to detect both braking operations and shift operations, and the controller merges the control logic for both functions into a single system, reducing overall system complexity while enabling transmission ratio changes during braking
Solution Approach 2:
The operating device is designed with multi-functionality, serving both as a brake operating device and a shift operating device. The single operating device can detect different types of user inputs (braking vs. shifting) and trigger appropriate responses, eliminating the need for separate control mechanisms and improving riding comfort through coordinated control
2Stability of the object's composition
If the shifting device is actuated during the play operating amount before braking starts, then the transmission ratio is smoothly changed, but the timing precision requirement increases to distinguish between braking and shifting operations
Solution Approach 1:
The controller is configured to actuate the shifting device during the play operating amount period, which occurs before the actual braking operation begins. This preliminary action allows the transmission ratio to be smoothly changed in advance, preparing the drivetrain for the upcoming braking event and ensuring continuous, jerk-free operation
Solution Approach 2:
The control system dynamically adjusts the shifting device actuation timing based on the detected operating state. By monitoring the operating device input in real-time and detecting the transition from neutral to braking operation, the system dynamically determines the optimal moment to actuate the shifting device, achieving smooth transmission ratio changes while adapting to varying user inputs
3Measurement precision
If the controller detects lever rotation angle, rotation speed, and operating force to control shifting, then the user request accuracy is improved, but the measurement and control complexity increases
Solution Approach 1:
The controller implements feedback control by detecting multiple parameters (lever rotation angle, rotation speed, and operating force) and using this information to adjust the shifting device actuation. The system continuously monitors these parameters and modifies the shifting response based on the detected operation state, ensuring accurate interpretation of user intent while maintaining coordinated control during braking
Solution Approach 2:
The control system utilizes changes in multiple physical parameters (angular position, angular velocity, and force) to determine the user's operational intent. By monitoring the combination and changes of these parameters over time, the system can distinguish between braking and shifting operations with high accuracy, enabling precise control decisions based on the detected operation state
Data Source
AI summary
To provide a shifting control device and an electric shifting system allowing a user to comfortably ride a human-powered vehicle, a shifting control device comprising a controller configured to control a shifting device in accordance with a first operation performed on an operating device for braking a rotary body of a human-powered vehicle.