Tether Orientation Sensor for UAV Position Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current systems for controlling the position of tethered unmanned aerial vehicles (UAVs) are prone to failure due to atmospheric conditions, radio frequency noise, and satellite integrity issues, leading to unreliable long-term operation.
Innovation Solution
A system that senses the two-dimensional angular strain on the UAV's tether at the attachment point using multiple strain sensors, combined with a gyroscope and accelerometer, to generate control signals that adjust the vehicle's orientation and position relative to the ground, ensuring stability and accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional visual or satellite navigation systems are used to maintain UAV position, then the system is simple to implement, but the reliability is low due to atmospheric conditions, radio frequency noise, and satellite integrity issues
Solution Approach 1:
The navigation system is segmented into multiple independent sensing components: strain sensors for tether angle measurement, gyroscope for angular rate detection, and accelerometer for linear acceleration measurement. Each sensor type independently contributes to position control, eliminating single-point failure modes and improving overall system reliability
Solution Approach 2:
The sensor suite serves multiple functions simultaneously: strain sensors detect tether orientation, gyroscope provides attitude information, and accelerometer contributes to both attitude and position data. This multi-functionality allows the system to maintain position through redundant measurement pathways, enhancing reliability without proportionally increasing complexity
2Measurement precision
If strain sensors are positioned at the tether connection point to sense angular strain, then the position measurement precision is improved, but the device complexity increases due to precise sensor placement requirements
Solution Approach 1:
Multiple strain sensors are merged into a single measurement system at the tether connection point. By arranging strain sensors in a specific geometric configuration (e.g., orthogonal pairs), the system simultaneously measures multiple components of tether angle and orientation, achieving high measurement precision while consolidating the sensing function at one location
Solution Approach 2:
The mechanical orientation sensing approach is replaced with electrical strain sensing. Instead of using complex mechanical angle encoders or visual orientation systems, the patent uses strain sensors that electrically measure tether tension components, providing precise angular information through electrical signals rather than mechanical linkages
3Measurement precision
If three or more strain sensors are disposed at the connection point to sense two-dimensional angular strain, then the measurement precision is improved, but the ease of manufacture decreases due to precise positioning requirements
Solution Approach 1:
The strain sensors are arranged in a symmetric geometric configuration (such as orthogonal pairs or equilateral triangle arrangement) around the tether connection point. This equipotential-like symmetry ensures that each sensor experiences equivalent mechanical conditions, simplifying the calibration and manufacturing process while maintaining high measurement precision across all sensing axes
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 system effectively maintains the UAV's position by sensing strain and orientation changes, providing reliable long-term operation by adjusting the vehicle's roll and pitch to counteract external forces like wind, thereby enhancing the reliability of tethered UAVs.
Implementation Method 1
Three or more strain sensors are disposed at, or near, the connection point between the tether and the UAV. The strain sensors sense a change in strain as the aircraft moves away from a normal above the desired position relative to ground
Implementation Method 2
A gyroscope and accelerometer may be positioned on the UAV. The gyroscope and accelerometer measure orientation of the tether relative to the direction of gravity
Implementation Method 3
A gyroscope and accelerometer may be positioned on the UAV. The gyroscope and accelerometer measure orientation of the tether relative to the direction of gravity
Data Source
AI summary
An unmanned aerial vehicle has a substrate. A tether sensor is mounted on the substrate. The tether sensor determines an orientation of the tether relative to the substrate. A micro controller, receiving the measured orientation from the tether sensor, determines an orientation of the tether relative to the substrate, and as a function of the orientation, determines a corrective value and outputs the corrective value to the unmanned aerial vehicle as at least one of a roll output and a pitch output control signal.