Knock Sensor Ultrasonic Signal Extraction for Motorcycle Engine Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for determining knocking in saddle-riding type vehicles, such as those based on audible range signal extraction from knock sensors, fail to accurately detect small knocking events that cause a harsh rider experience due to the interference from mechanical noise.
Innovation Solution
A power unit for saddle-riding type vehicles that includes a knock sensor detecting vibrations in both audible and ultrasonic ranges, with a control apparatus extracting ultrasonic components with a higher gain than audible components to determine knocking occurrences, allowing for precise control of engine combustion and reduction of harsh knocking sounds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If signal extraction in audible range is applied to detect knocking, then human-hearing compatible knocking can be determined, but small knocking that causes harsh feeling cannot be accurately detected due to mechanical noise interference
Solution Approach 1:
The patent segments the vibration signal into different frequency ranges (audible range and ultrasonic range) and processes each range separately. By extracting ultrasonic components with larger gain, the system can detect small knocking events that are masked by mechanical noise in the audible range, thereby improving measurement precision while filtering out harmful noise interference.
Solution Approach 2:
The patent applies different gain values to different frequency components of the vibration signal. Specifically, ultrasonic range components are extracted with larger gain than audible range components. This local quality approach allows the system to enhance sensitivity to small knocking events in the ultrasonic range while maintaining noise rejection in the audible range.
2Measurement precision
If ultrasonic range components are extracted with larger gain, then small knocking can be accurately detected, but device complexity increases due to frequency separation processing
Solution Approach 1:
The patent divides the vibration signal processing into frequency-based segments, extracting ultrasonic range components with larger gain. This segmentation enables accurate detection of small knocking while maintaining a relatively simple processing architecture by focusing on specific frequency bands rather than attempting to process the entire spectrum with equal complexity.
3Object-affected harmful factors
If knocking detection sensitivity is increased to detect small knocking, then rider comfort improves, but false detection from mechanical noise increases
Solution Approach 1:
By segmenting the signal into audible and ultrasonic frequency ranges and applying different gain values, the patent enhances detection of small knocking that causes rider discomfort while maintaining reliable operation. The ultrasonic range extraction with larger gain provides the sensitivity needed to detect subtle knocking events without being overwhelmed by mechanical noise in the audible range.
Solution Approach 2:
The patent applies local quality by assigning different gain characteristics to different frequency components. This allows the system to optimize sensitivity specifically for the ultrasonic range where small knocking manifests, while maintaining lower gain for audible range components where mechanical noise dominates, thereby improving both rider comfort and detection reliability.
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 enables accurate detection and control of small knocking events, improving the rider experience by reducing audible range vibrations that were previously masked by mechanical noise, ensuring efficient engine combustion without frequent knocking.
Implementation Method 1
a knock sensor that detects vibration of the engine
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a saddle-riding type vehicle and a power unit of the saddle-riding type vehicle that can efficiently control combustion of an engine while controlling and reducing the occurrence of knocking that is harsh for the rider. The saddle-riding type vehicle and the power unit include: an engine; and a control apparatus that controls combustion of the engine, in which the engine is configured so that vibration in an audible range and vibration in an ultrasonic range are generated by knocking, and the control apparatus includes a knock sensor that detects vibration of the engine, in which: the control apparatus extracts components in the ultrasonic range with a larger gain than that of components in the audible range from a detection signal of the knock sensor; the control apparatus determines that knocking occurs based on the detection signal in which the components in the ultrasonic range are extracted with a larger gain than that of the components in the audible range; and the control apparatus controls the combustion of the engine based on a determination result of the occurrence of knocking.