Strapdown Gravity Sensors on UAVs for Subsurface Surveys
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing gravity survey methods are slow, expensive, and inaccessible for large areas, requiring trained professionals, aircraft, and specialized equipment, and are hindered by international regulations, limiting their effectiveness in identifying underground resources.
Innovation Solution
Integration of a strapdown gravity sensor on a multirotor UAV for conducting gravity prospecting, utilizing a GNSS and RTK-GNSS base station to measure and filter gravitational acceleration, removing kinematic acceleration, and determining gravity anomalies.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If ground gravity surveys are conducted by physically visiting each data point with a gravimeter, then measurement precision is improved, but productivity deteriorates due to slow surveying speed and high cost
Solution Approach 1:
The patent replaces the mechanical ground-based gravimeter system with an airborne UAV platform carrying a gravity sensor. This substitution allows the survey to cover large areas quickly while maintaining measurement precision through sensor integration and data processing algorithms that compensate for platform motion.
Solution Approach 2:
The patent introduces GPS/INS (Global Positioning System/Inertial Navigation System) as an intermediary to track and correct for the motion of the UAV platform. This mediator system measures the platform's acceleration and position, then uses this data to compensate for motion effects in the gravity measurements, enabling high-speed airborne surveying without sacrificing accuracy.
2Productivity
If airborne gravity surveys are conducted by flying a gravimeter in an aircraft, then productivity is improved, but device complexity worsens due to requirements for aircraft, pilots, and airport access
Solution Approach 1:
The patent replaces expensive, complex manned aircraft with relatively simple, unstaffed UAVs (unmanned aerial vehicles). These UAVs can be deployed without requiring airport infrastructure or licensed pilots, dramatically reducing operational complexity and cost while maintaining the ability to conduct airborne gravity surveys over large areas.
Solution Approach 2:
The UAV system is designed to operate autonomously without human intervention during the survey. The vehicle navigates, collects data, and transmits information automatically, eliminating the need for pilots and ground crews. This self-service capability simplifies the overall system complexity while preserving productivity benefits.
3Measurement precision
If low-altitude terrain-following flights are conducted to improve spatial resolution, then measurement precision is improved, but ease of operation deteriorates due to requirement for specially trained pilots
Solution Approach 1:
The patent replaces the need for skilled human pilots with an automated flight control system. This mechanical/electronic substitution allows the UAV to execute complex low-altitude terrain-following flight paths without requiring specially trained operators, making the system easier to operate while maintaining high spatial resolution through consistent low-altitude flight.
Solution Approach 2:
The patent employs dynamic, real-time flight path adjustment capabilities in the UAV control system. The vehicle can automatically adapt its flight altitude and trajectory to follow terrain contours, maintaining optimal survey conditions without human intervention. This dynamic control enables complex maneuvers that would require extensive pilot training to execute manually.
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
Enables high-accuracy, cost-effective, and accessible gravity surveys over large regions, improving subsurface exploration for mineral deposits and other features.
Implementation Method 1
measuring total acceleration of a UAV during a gravity survey mission with a strapdown gravity sensor mounted to the UAV
Implementation Method 2
obtaining kinematic acceleration of the UAV using the GNSS satellite signal and the correction factor signal
Data Source
AI summary
Systems and methods described integrate a strapdown gravity sensor such as a gravimeter on an unstaffed aerial vehicle to conduct gravity prospecting for identifying surface and subsurface features of interest.