Infant Seat Motion Profile Design With Constant-Speed Motors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing infant care devices, such as bouncy seats and baby swings, lack the ability to provide simultaneous or independent movement in two dimensions, limiting their ability to mimic the natural motion profiles of a caregiver, which can be soothing and entertaining for infants.
Innovation Solution
A motorized infant chair with a vertical reciprocating assembly and a horizontal reciprocating assembly, each driven by a motor, allowing for simultaneous or independent movement in two dimensions and capable of reproducing a variety of motion profiles, including sinusoidal movements with smooth acceleration and deceleration, using encoders and limit switches for precise control.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a single motorized degree of freedom is used, then the device can be simpler, but it is limited in the motion profiles that can be generated
Solution Approach 1:
The device is divided into two separate motorized assemblies: a vertical reciprocating assembly and a horizontal reciprocating assembly. Each assembly independently controls one dimension of motion, allowing the system to generate complex motion profiles by combining simpler individual motions. This segmentation enables versatile motion control without requiring an overly complex single mechanism.
Solution Approach 2:
The patent transitions from single-dimensional motion control to two-dimensional motion control by adding both vertical and horizontal reciprocating assemblies. This dimensional expansion allows the seat to reproduce complex caregiver motion patterns that cannot be achieved with a single degree of freedom, significantly improving adaptability while maintaining manageable complexity through modular design.
2Adaptability or versatility
If motors are run at variable speeds to achieve different motion profiles, then motion control is more flexible, but speed control complexity increases
Solution Approach 1:
The patent achieves different motion profiles by changing the parameters of reciprocating motion (amplitude, frequency, phase) rather than requiring continuous variable speed control. The motors run at substantially constant speeds, and the desired motion variety is obtained by adjusting the mechanical parameters of the reciprocating assemblies, such as crank lengths and stroke distances, which simplifies the control system while maintaining flexibility.
Solution Approach 2:
The system uses periodic reciprocating motion generated by mechanical assemblies (such as crank mechanisms) to produce different motion profiles. By varying the phase and frequency of the periodic motions between the vertical and horizontal assemblies, the system can create complex motion patterns without requiring variable speed motors, thereby reducing control complexity.
Data Source
AI summary
A variable motion infant seat includes: a vertical reciprocating assembly comprising a first motor for providing vertical motion; a horizontal reciprocating assembly coupled to the vertical reciprocating assembly and comprising a second motor for providing horizontal motion; and a support device coupled to at least one of the vertical reciprocating assembly and the horizontal reciprocating assembly. The first motor and second motor are run at a substantially constant speed, thereby causing the vertical reciprocating assembly and horizontal reciprocating assembly to move the support device in at least one motion profile.