Chainless E-Bike Pedal-Wheel Synchronization for Natural Riding Feel
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Solution Overview
Problem
Chainless electric bicycles lack the pedaling feeling and driving feeling experienced in bicycles with a chain due to unsynchronized rotational positions of the pedal and driving wheel, and inadequate response to road gradients and pedal acceleration.
Innovation Solution
A device and method for controlling a chainless electric bicycle that synchronizes the rotational positions of the pedal and driving wheel using sensors and a controller to adjust generator and motor currents based on measured positions and road gradients, ensuring synchronized rotation and appropriate torque.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Loss of energy
If regenerative braking is implemented to recover energy during deceleration, then energy efficiency is improved, but system complexity increases due to additional control mechanisms
Solution Approach 1:
The patent combines the regenerative braking function with the existing motor controller, integrating energy recovery control into the existing drive system rather than adding a completely separate control unit. The motor controller simultaneously manages motor drive and regenerative braking operations, merging multiple functions into a single control device.
Solution Approach 2:
The motor controller is designed to perform multiple functions including motor drive control, regenerative braking control, and battery management. This multi-functional approach allows the system to recover energy during deceleration while using the same control hardware for normal operation, reducing overall system complexity.
2Reliability
If multiple sensors and control units are added to optimize motor performance and battery management, then riding comfort and safety are improved, but device complexity increases
Solution Approach 1:
The patent integrates multiple control functions including motor control, battery management, and sensor data processing into a single motor controller unit. This consolidation reduces the number of separate control units while maintaining comprehensive system monitoring and control capabilities.
Solution Approach 2:
The motor controller is designed as a multi-functional device that simultaneously handles motor drive signals, regenerative braking control, battery state monitoring, and sensor data acquisition. This universal control unit performs multiple roles that would traditionally require separate dedicated controllers.
3Device complexity
If a hub motor integrating drive and wheel functions is used, then structure is simplified, but manufacturing precision requirements increase
Solution Approach 1:
The patent employs a hub motor that integrates the drive motor, wheel, and brake components into a single unified structure. This integration simplifies the overall vehicle structure by eliminating the need for separate drive train components and reduces the number of mechanical connections required.
Solution Approach 2:
The hub motor performs multiple functions simultaneously - providing propulsion, enabling regenerative braking, and serving as the wheel itself. This multi-functional integration reduces structural complexity while consolidating multiple subsystems into a single component that requires precise manufacturing.
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
The device provides a pedaling feeling similar to bicycles with a chain by synchronizing pedal and wheel rotations, and enhances torque response to road gradients, improving the overall riding experience.
Implementation Method 1
When the user operates the brake unit, the bicycle is decelerated while the generator unit generates electrical energy through electromagnetic induction, and the battery unit accumulates the generated electrical energy
Implementation Method 2
the generator unit generates electrical energy through electromagnetic induction
Data Source
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AI summary
The present invention relates to a system for driving a chainless electric bicycle comprising: a driving wheel; a pedal; a motor mechanically connected to the driving wheel; a generator mechanically connected to the pedal; and a battery, wherein provided is a system comprising: a generator location sensor for measuring the value of a rotation location of the generator; a motor location sensor for measuring the value of a rotation location of the motor; and a controller configured to calculate a difference value of the value of the rotation location of the motor minus the value of the rotation location of the generator multiplied by a gear ratio, and to control at least one of the generator and the motor on the basis of the difference value.