aximum velocity and radius
            vmax = 0;
            rmax = 0;
            
            % Outer loop over reference particles
            for i = 1:drv.n_particles
                p1 = drv.particles(i);
                
                % Update maximum velocity
                if (this.auto_freq)
                    vparticle = vecnorm(p1.veloc_trl);
                    if (vparticle > vmax)
                        vmax = vparticle;
                    end
                    if (p1.radius > rmax)
 