Road Surface Monitoring via Free-Rolling Tire Slip Estimation

The patent uses standard vehicle sensors (wheel speed sensor, vehicle speed sensor) as intermediaries to indirectly measure tire slip. Instead of directly measuring slip with a specialized accelerometer in the tire, the system uses readily available sensors that measure wheel and vehicle speeds, then calculates slip as the difference between these speeds. This intermediary approach resolves the contradiction by achieving measurement precision through calculation rather than direct measurement, avoiding the need for complex sensor installation.

The patent replaces the mechanical measurement system (physical accelerometer in the tire) with a computational system. The slip estimation is performed through signal processing and calculation using data from standard sensors, rather than through direct mechanical measurement. This substitution resolves the contradiction by eliminating the need for specialized hardware while maintaining the ability to quantify tire slip.

The patent makes the slip detection system universal by using standard vehicle sensors that are already present in most vehicles. These sensors serve multiple functions: monitoring wheel speed for ABS/ESC systems, providing data for tire slip calculation, and enabling road condition detection. This multi-functionality resolves the contradiction by ensuring reliability through proven sensor technology while dramatically improving ease of manufacture, as no additional specialized components need to be installed.

The system leverages the existing sensor infrastructure in vehicles to provide slip detection functionality. The standard wheel speed and vehicle speed sensors, already installed for other safety systems, are utilized to generate slip information without requiring separate dedicated sensors. This self-service approach resolves the contradiction by achieving reliable detection through existing systems while eliminating the need for additional manufacturing complexity.

The patent applies preliminary signal processing and filtering to the data from standard sensors before calculating slip. The system prepares the input signals by filtering noise and validating data quality, which enhances the precision of the subsequent slip calculation. This preliminary action resolves the contradiction by ensuring that even though standard sensors are used (improving ease of manufacture), the measurement precision is maintained through careful signal preparation and processing.

The system continuously monitors the estimated slip values and uses this information to refine road condition classification. The feedback loop allows the system to adapt to varying driving conditions and improve estimation accuracy over time. This feedback mechanism resolves the contradiction by compensating for the limitations of standard sensors through continuous validation and adaptation, maintaining measurement precision while benefiting from the ease of using existing sensor infrastructure.