Compared with conventional percussion sensing systems that rely on external power sources, self-powered triboelectric nanogenerators (TENGs) especially employing aluminum coordination hydrogel (Al-HG) composites as electrode material offer broader application prospects. However, the weak infiltration and combination between Al 3+ and functional ligands results in poor mechanical performance. Herein, a “subject–object” multi-scale regulation strategy is proposed to construct tough and stable Al-HG 3 composites, based on which a flexible self-powered TENG sensing system is developed to enable visualized percussion performance. In detail, through acidic pretreatment, alkaline modulation, and low-temperature enhancement, an Al-HG 3 with remarkable improvements in tensile performance, compressive property, fatigue resistance, and anti-swelling capability is obtained. By integrating the Al-HG 3 with a triboelectric layer, the constructed Al-HG 3-TENG enables highly sensitive recognition and digital processing of rhythm and striking force, showing promise in percussion instruments exemplified by African drum. Without external power, it achieves real-time, visual signal acquisition, and intelligent analysis of percussion input, showing great potential for applications in intelligent musical interaction and the integration of art and technology. This work not only provides theoretical innovation in material design and mechanical optimization of metal coordination hydrogels but also presents an engineering-ready solution at the inter of flexible electronics and musical engineering.