We investigate collision dynamics of vector solitons in the fractional coupled cubic–quintic nonlinear Schrödinger system. Using symplectic split-step Fourier simulations with spectral accuracy, we scan the Lévy index \(\alpha \) and initial relative velocity v to map the control landscape of soliton interactions. Results show that fractional dispersion governs collision inelasticity, waveform compression, and radiation emission. As \(\alpha \) decreases from the integer-order limit, enhanced nonlocal effects produce stronger transient compression during collision and increased radiation. A strong-interaction regime is identified within \(\alpha \in [1.4, 1.8]\) , where soliton overlap and post-collision density reach maxima. Velocity scanning reveals that moderate initial velocities minimize soliton separation and enhance nonlinear trapping, while higher velocities intensify deformation and radiative loss. Despite substantial waveform modulation, the collision-induced velocity shift remains approximately invariant across parameter regimes, suggesting an emergent kinematic robustness observed at the level of center-of-mass dynamics. Numerical fidelity is confirmed by optical power conservation errors below \(0.15\%\) . These findings establish a quantitative framework for controlling vector soliton collisions in fractional nonlinear media, with applications to soliton-based photonic switching and signal processing devices.
