Abstract: Methods and apparatus are described for drone collision avoidance that includes extracting first feature information from an image. The image is captured from a first camera oriented in a direction. Second feature information is received from an external source. The second feature information is extracted from a second image of the environment captured by a second camera oriented in the direction. The first feature information and the second feature information are matched. A second local frame of reference of the second feature information is transformed to a first local frame of reference of the first feature information to determine a location of the external source. If a collision with the external source will occur is determined based on the location of the external source and a current flight trajectory.

Abstract: Methods and apparatus for preventing collisions between drones based on drone-to-drone acoustic communications are disclosed. A control system of a first drone includes a route manager to command the first drone to track a first route. The control system further includes a plurality of acoustic sensors arranged on the first drone to detect acoustic signals. The control system further includes a collision prevention engine to determine a second route based on acoustic signals detected by the acoustic sensors, the acoustic signals being received from a second drone while the first drone is tracking the first route. The second route differs from the first route to prevent a drone-to-drone collision between the first drone and the second drone. The collision prevention engine is to cause the route manager to command the first drone to track the second route instead of the first route.

Abstract: Methods, systems, and apparatus for audio noise reduction from a drone are disclosed. An example apparatus includes a first sensor to gather acoustic data and a second sensor to gather rotational motion data of a rotor. The example apparatus also includes an analyzer to match the rotational motion data to a filter and filter the acoustic data using the filter. The analyzer also is to generate an audio signal based on the filtered acoustic data.

Abstract: Systems and methods include receiving, values of one or more first external time variables from a first external node and values of one or more second external time variables from a second external node. The values of one or more local time variables of the local node are adjusted based at least upon the values of the one or more first external time variables and the values of the one or more second external time variables.

Abstract: Systems and methods include receiving, values of one or more first external time variables from a first external node and values of one or more second external time variables from a second external node. The values of one or more local time variables of the local node are adjusted based at least upon the values of the one or more first external time variables and the values of the one or more second external time variables.