Rallylens App Uses AI Video Analysis to Give Tennis Players Coach-Like Feedback

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A student tennis player has developed Rallylens, a web app that uses AI-powered video analysis to help players improve their technique without a coach present. The tool breaks uploaded tennis videos into frames, classifies stroke types such as forehands, backhands, and serves, and compares them against biomechanical benchmarks with an 85% accuracy rate. When flaws are detected, the system generates specific, actionable feedback — for example, recommending precise adjustments to shoulder tilt or wrist rotation. The app has notable limitations, including sensitivity to poor video quality, difficulty with unconventional playing styles, and an inability to account for psychological factors affecting performance. Its creators position Rallylens not as a coach replacement but as a supplementary tool to make quality technique feedback more accessible, especially for players in remote areas or with limited coaching budgets.

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