An autonomous vehicle may include a stuck condition detection component and a communications component. The stuck-detection component may be configured to detect a condition in which the autonomous vehicle is impeded from navigating according to a first trajectory. The communications component may send an assistance signal to an assistance center and receive a response to the assistance signal. The assistance signal may include sensor information from the autonomous vehicle. The assistance center may include a communications component and a trajectory specification component. The communications component may receive the assistance signal and send a corresponding response. The trajectory specification component may specify a second trajectory for the autonomous vehicle and generate the corresponding response that includes a representation of the second trajectory. The second trajectory may be based on the first trajectory and may ignore an object that obstructs the first trajectory.