A system configured to implement an acoustic beam steering array in an autonomous vehicle comprising: a sensor system, configured to sense an environment external to the autonomous vehicle and to generate sensor data; a planner system, configured to calculate an autonomous vehicle trajectory for the autonomous vehicle in the environment; an acoustic beam steering array coupled to the autonomous vehicle, the acoustic beam steering array comprising a plurality of speakers configured to output directional audio; and one or more processors configured to perform operations, including: determining, based on the sensor data generated by the sensor system, an object position and an object type of the object; determining, based at least in part on the object type and the object position, a predicted motion of the object in the environment; estimating, based at least in part on the predicted motion of the object and the autonomous vehicle trajectory calculated by the planner system, a threshold location in the environment; determining, based on the determined object position, a direction to emit a beam of acoustic energy via the plurality of speakers of the acoustic beam steering array; selecting an audio signal based at least in part on at least one of a distance of the object to the autonomous vehicle or a likelihood of a collision between the object and the autonomous vehicle, the likelihood of the collision being determined based on the predicted motion; and causing, when the determined position of the object coincides with the estimated threshold location, the plurality of speakers to emit the audio signal as the beam of acoustic energy indicative of an alert in the determined direction; wherein: selecting the audio signal is also based on the determined object type. a sensor system, configured to sense an environment external to the autonomous vehicle and to generate sensor data; a planner system, configured to calculate an autonomous vehicle trajectory for the autonomous vehicle in the environment; an acoustic beam steering array coupled to the autonomous vehicle, the acoustic beam steering array comprising a plurality of speakers configured to output directional audio; and one or more processors configured to perform operations, including: determining, based on the sensor data generated by the sensor system, an object position and an object type of the object; determining, based at least in part on the object type and the object position, a predicted motion of the object in the environment; estimating, based at least in part on the predicted motion of the object and the autonomous vehicle trajectory calculated by the planner system, a threshold location in the environment; determining, based on the determined object position, a direction to emit a beam of acoustic energy via the plurality of speakers of the acoustic beam steering array; selecting an audio signal based at least in part on at least one of a distance of the object to the autonomous vehicle or a likelihood of a collision between the object and the autonomous vehicle, the likelihood of the collision being determined based on the predicted motion; and causing, when the determined position of the object coincides with the estimated threshold location, the plurality of speakers to emit the audio signal as the beam of acoustic energy indicative of an alert in the determined direction; wherein: selecting the audio signal is also based on the determined object type. determining, based on the sensor data generated by the sensor system, an object position and an object type of the object; determining, based at least in part on the object type and the object position, a predicted motion of the object in the environment; estimating, based at least in part on the predicted motion of the object and the autonomous vehicle trajectory calculated by the planner system, a threshold location in the environment; determining, based on the determined object position, a direction to emit a beam of acoustic energy via the plurality of speakers of the acoustic beam steering array; selecting an audio signal based at least in part on at least one of a distance of the object to the autonomous vehicle or a likelihood of a collision between the object and the autonomous vehicle, the likelihood of the collision being determined based on the predicted motion; and causing, when the determined position of the object coincides with the estimated threshold location, the plurality of speakers to emit the audio signal as the beam of acoustic energy indicative of an alert in the determined direction; wherein: selecting the audio signal is also based on the determined object type.