3D Drum Optical Encoder for Low-Stack Autolacing Footwear
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Solution Overview
Problem
Conventional optical encoders used in motorized lacing systems for footwear are fragile and have a high stack-up, which can compromise the performance and robustness of athletic footwear, and their manufacturing precision raises costs and reliability issues.
Innovation Solution
A three-dimensional optical encoder based on a rotary drum design is developed, which is more compact, robust, and easier to manufacture, featuring a cylindrical shape with alternating dark and reflective segments on its exterior surface, allowing for greater variance in manufacturing processes and improved durability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional optical encoders are used in motorized lacing systems, then rotational tracking function is provided, but the encoder is fragile and has high stack-up which compromises performance and robustness
Solution Approach 1:
The patent transitions from a conventional planar (2D) optical encoder to a three-dimensional (3D) optical encoder with a drum-shaped rotating member. This dimensional change allows the encoder to achieve compactness in the stack-up direction while maintaining rotational tracking functionality, directly resolving the contradiction between reliability and device complexity.
Solution Approach 2:
The rotating member is designed with a drum shape (cylindrical geometry) rather than a flat disk. This curved/spheroidal form factor reduces the encoder's stack-up height while maintaining structural integrity and rotational capability, improving both reliability and reducing device complexity.
2Measurement precision
If conventional optical encoders with high manufacturing precision are used, then measurement accuracy is maintained, but manufacturing costs increase and reliability issues arise
Solution Approach 1:
By moving to a 3D drum configuration, the patent allows for more tolerant manufacturing processes compared to precision planar encoders. The three-dimensional structure provides natural alignment features and reduces sensitivity to manufacturing variations, lowering costs while maintaining measurement precision.
Solution Approach 2:
The patent changes the geometric parameters of the encoder from a flat 2D structure to a 3D drum structure with specific dimensional relationships. This parameter change enables the use of less precision-critical manufacturing processes while maintaining the required measurement accuracy through the optical detection mechanism.
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 three-dimensional optical encoder enhances the reliability and robustness of motorized lacing systems, reducing manufacturing costs and improving the performance of athletic footwear by providing accurate rotational tracking with increased tolerance for manufacturing variations and wear.
Implementation Method 1
a first optical sensor and a second optical sensor within an optical range of the three-dimensional optical encoder
Data Source
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AI summary
An article of footwear and related method includes a midsole, an upper secured with respect to the midsole, and a lace extending through the upper. A motorized lacing system positioned within the midsole, configured to engage with the lace to increase and decrease tension on the lace. The motorized lacing system includes a motor, including a motor shaft, a spool, coupled to the motor shaft, configured to spool and unspool the lace based on the turning of the motor shaft, a processor circuit, and an optical encoder. The optical encoder comprises a three-dimensional encoder defining a major axis and having a surface having a first plurality of segments positioned between a second plurality of segments, and an optical sensor, positioned within optical range of the cylindrical encoder, configured to output a signal to the processor circuit indicative of a detected one of a first and second plurality of segments.