Techniques for controlling downhole drilling equipment include determining a nominal model of downhole drilling dynamics based on sensor measurements from the downhole drilling equipment; determining an uncertainty for the nominal model of downhole drilling dynamics; determining, based on the uncertainty for the nominal model of downhole drilling dynamics, a set of models that deviate from the nominal model of downhole drilling dynamics; and generating a virtual controller for the downhole drilling equipment based on the nominal model and the set of models that deviate from the nominal model.