We study the mobility law of dislocations in aluminum as an important building block for the development of a multiscale method that couples an atomistic model with discrete dislocation dynamics in 3d (\eg CADD3d). Straight dislocations of arbitrary character angles are modeled with classical molecular dynamics at several temperatures. The obtained mobility results are analyzed and validated by comparisons to theoretical models. A critical velocity parameter identified by the analytic models is correlated to the material dispersive nature. We revisit the interpretation of this constant by considering character angles that were not studied previously. Finally, the obtained mobility law is implemented and employed in the discrete dislocation dynamics simulation of a dislocation loop. Our results highlight the importance of including several angles when constructing the mobility law to produce consistent results.