Ultrasonic Sensor Drive Timing for Accurate Reflection Discrimination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ultrasonic sensors face challenges in accurately discriminating reflection waves due to long driving durations of the ultrasonic oscillation element, leading to inefficiencies and reduced accuracy, especially when transformers are not used.
Innovation Solution
A driving device with a transmission wave signal generation circuit that generates signals with specific frequency transitions and a driving circuit that allocates different times for these transitions, along with a boost circuit to maintain voltage, ensuring efficient and accurate discrimination of reflection waves without a transformer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the ultrasonic oscillation element is driven for a long duration, then the power supply voltage can be maintained without a boost circuit, but the accuracy of reflection wave discrimination deteriorates
Solution Approach 1:
The patent applies dynamics by making the driving duration variable rather than fixed. The driving circuit dynamically adjusts the driving duration based on the oscillation frequency: longer duration for frequencies far from resonance, shorter duration for frequencies close to resonance. This dynamic adjustment resolves the contradiction by optimizing both power stability and measurement accuracy for different operating conditions.
Solution Approach 2:
The patent changes the parameter of driving duration based on the oscillation frequency parameter. By detecting the oscillation frequency and adjusting the driving duration accordingly, the system adapts to different resonance conditions. This parameter change strategy allows the system to maintain power stability when needed while preventing measurement accuracy degradation when oscillation frequency is close to resonance.
2Measurement precision
If the driving duration is shortened to improve reflection wave discrimination accuracy, then power efficiency improves, but the power supply voltage drops without a boost circuit
Solution Approach 1:
The system dynamically adjusts driving duration to balance measurement accuracy and power consumption. Rather than using a fixed short duration that would cause voltage drops, or a fixed long duration that reduces accuracy, the system adapts the duration based on real-time oscillation frequency detection, optimizing both accuracy and power efficiency for each operating condition.
Solution Approach 2:
The driving duration parameter is changed based on the oscillation frequency parameter. When oscillation frequency is close to resonance, the duration is shortened to improve accuracy. When frequency is far from resonance, the duration is extended to maintain power supply voltage. This conditional parameter adjustment resolves the contradiction between accuracy and power maintenance.
3Use of energy by moving object
If the oscillation frequency is set close to the resonance frequency to improve power efficiency, then the response to frequency changes deteriorates
Solution Approach 1:
The system dynamically adjusts the driving duration based on how close the oscillation frequency is to the resonance frequency. When the frequency is close to resonance, the driving duration is shortened to maintain power efficiency while accepting reduced response speed. When the frequency is far from resonance, the driving duration is extended to improve response speed. This dynamic adaptation resolves the contradiction between power efficiency and response speed.
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
This approach enhances the response of the ultrasonic oscillation element to frequency changes, improving the accuracy of reflection wave discrimination and maintaining power efficiency during short driving durations.
Implementation Method 1
An ultrasonic sensor generates an ultrasonic wave and measures the time that the so generated ultrasonic wave takes to strike an object and returns to the ultrasonic sensor
Implementation Method 2
a boost circuit to maintain voltage, ensuring efficient and accurate discrimination of reflection waves without a transformer
Data Source
AI summary
A driving device includes a transmission wave signal generation circuit configured to generate a transmission wave signal, and a driving circuit configured to drive an ultrasonic oscillation element based on the transmission wave signal. The driving circuit has an initial driving sequence in which the driving circuit generates the transmission wave signal at an initial frequency, a first transition sequence in which the driving circuit generates the transmission wave signal during its transition from the initial frequency to a first frequency, and a second transition sequence in which the driving circuit generates the transmission wave signal during its transition from the first frequency to a second frequency. The initial frequency and the second frequency are closer than the first frequency, to the resonance frequency of the ultrasonic oscillation element. The first transition sequence is allotted a longer time than the time allotted to the second transition sequence.