Tetrahedral Antenna Module for Mobile Robot Ranging
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Mobile lawn-mowing robots face challenges in accurately determining ranging and angle of arrival information from beacons due to limited real estate on the robot and signal distortions caused by structural components and the environment.
Innovation Solution
A tetrahedral geometry antenna module with a ranging antenna and three axisymmetrically arranged angle antennas is mounted on the robot, along with calibration techniques to improve accuracy by computing phase difference of arrival (PDOA) values and adjusting for distortions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple antennas are deployed to improve ranging and angle of arrival determination accuracy, then measurement precision is improved, but device complexity and space requirements increase
Solution Approach 1:
The antenna system is segmented into four distinct antenna elements (one ranging antenna and three angle antennas) arranged in a tetrahedral geometry. Each antenna serves a specific function in determining spatial parameters, allowing the system to achieve high measurement precision through distributed sensing while managing complexity through functional segmentation.
Solution Approach 2:
The patent transitions from a planar antenna arrangement to a three-dimensional tetrahedral configuration. By positioning antennas in 3D space with specific spatial relationships, the system achieves superior angle of arrival determination capability. The tetrahedral geometry provides baseline separation in multiple dimensions, enabling accurate spherical triangulation for ranging and direction finding.
2Measurement precision
If antenna separation distance is increased to improve signal reception and angle determination, then measurement precision improves, but the area occupied on the robot increases
Solution Approach 1:
The patent utilizes three-dimensional spatial arrangement instead of increasing planar separation. The tetrahedral configuration achieves the required baseline distances for accurate angle determination by extending into the vertical dimension, thereby maintaining a compact footprint on the robot surface while providing sufficient antenna separation for precise signal processing.
Solution Approach 2:
The patent optimizes the antenna separation distance to be less than one-half wavelength of the operating frequency. This parameter optimization ensures that the antennas are close enough to minimize spatial requirements on the robot, while still maintaining sufficient baseline for accurate phase difference measurement and angle of arrival determination through sophisticated signal processing algorithms.
3Measurement precision
If calibration techniques are implemented to account for antenna positions and signal distortions, then measurement precision improves, but device complexity and processing requirements increase
Solution Approach 1:
The patent implements preliminary calibration procedures to determine and store correction parameters for antenna position offsets and environmental signal distortions before actual operation. By pre-characterizing the antenna array response and storing calibration data, the system eliminates the need for complex real-time calibration computations during navigation, thereby improving measurement precision without significantly increasing operational processing complexity.
Solution Approach 2:
The system employs feedback mechanisms where measured phase differences and signal characteristics are continuously compared against calibrated reference values. Correction parameters are applied based on the deviation between expected and actual measurements, enabling the system to compensate for positional offsets and environmental distortions dynamically, thereby maintaining high measurement precision through adaptive correction.
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 solution allows for precise determination of ranging and angle of arrival information without occupying substantial robot space, enhancing navigation and localization accuracy by accounting for antenna positions and signal distortions.
Implementation Method 1
an antenna assembly mounted to the base assembly by a spring
Implementation Method 2
The antenna assembly includes a ranging antenna, and at least three angle antennas arranged axisymmetrically about the ranging antenna, such that the ranging antenna and the three angle antennas define a tetrahedral geometry for determining an angle of arrival for one or more incident signals
Data Source
AI summary
A mobile robot includes a chassis, a shell moveably mounted on the chassis, and a cutting assembly mounted to the chassis. The mobile robot also includes a communication system that includes an antenna module disposed on a rear portion of the mobile robot. The antenna module includes a base assembly, and an antenna assembly mounted to the base assembly by a spring. The antenna assembly includes a ranging antenna, and at least three angle antennas arranged axisymmetrically about the ranging antenna, such that the ranging antenna and the three angle antennas define a tetrahedral geometry for determining an angle of arrival for one or more incident signals.