Autonomous convoys maneuvering “deformable” terrain and “deformable” obstacles
The path of a lead autonomous vehicle moving through “deformable” terrain is shared between the lead autonomous vehicle and the following autonomous vehicles. The lead autonomous vehicle records distances to 3D obstacles and whether to drive through them, and the following autonomous vehicles will classify different “obstacles” that were driven through by the leader and allow the planner to drive through them. In “deformable” terrain, errors in wheel odometry will be recorded by the lead autonomous vehicle and the following autonomous vehicles are informed that similar problems will be encountered. These errors are sensed by discrepancies between odometry and inertial and visual odometry.
1. A system for traversing deformable terrain or obstacles, the system comprising:
a plurality of autonomous vehicles in a convoy, each autonomous vehicle comprising:
a sensor operable to sense terrain or obstacles in an environment to be traversed by the autonomous vehicle;
a wheel odometer operable to measure distance traversed by the autonomous vehicle based on rotation of a wheel of the autonomous vehicle;
a communication mechanism operable to transmit one or more signals between the autonomous vehicle and other autonomous vehicles in the convoy; and
a processor,
wherein the processor of a lead autonomous vehicle in the convoy is operable to execute stored instructions to:
classify, based on one or more signals from the sensor, a sensed terrain or a sensed obstacle as deformable;
plan a route for the lead autonomous vehicle that traverses the terrain or obstacle classified as deformable;
determine an error for the wheel odometer resulting from the traversing the terrain or obstacle classified as deformable; and
send, via the communication mechanism to a following autonomous vehicle in the convoy, one or more communication signals indicating (i) the terrain or obstacle classified as deformable and (ii) the determined error for the wheel odometer; and
wherein the terrain or obstacle classified as deformable comprises ground vegetation, tree limbs, dirt, mud, or any combination thereof.
2. The system of claim 1 , wherein:
the one or more communication signals further indicate the route planned for the lead autonomous vehicle; and
the processor of a following autonomous vehicle in the convoy is operable to execute stored instructions to:
receive, via the communication mechanism, the one or more communication signals from the lead autonomous vehicle; and
plan, based on the route planned for the lead autonomous vehicle, a route for the following autonomous vehicle that traverses the terrain or obstacle classified as deformable by the lead autonomous vehicle.
3. The system of claim 1 , wherein the processor of a following autonomous vehicle in the convoy is operable to execute stored instructions to:
receive, via the communication mechanism, the one or more communication signals from the lead autonomous vehicle; and
adjust, based on the error determined by the lead autonomous vehicle, a measurement by the wheel odometer to compensate for an error expected to result from traversing the terrain or obstacle classified as deformable.
4. The system of claim 1 , wherein:
the lead autonomous vehicle in the convoy further comprises a secondary odometer operable to measure distance traversed using inertial and visual measurements; and
the processor of the lead autonomous vehicle is further operable to execute stored instructions to determine the error for the wheel odometer based on a discrepancy between a measurement by the wheel odometer and a measurement by the secondary odometer.
5. The system of claim 2 , wherein the processor of the following autonomous vehicle is further operable to execute stored instructions to preclude the following autonomous vehicle from accelerating during the traversing of the terrain or obstacle classified as deformable by the lead autonomous vehicle.
6. The system of claim 1 , wherein the processor of the lead autonomous vehicle is further operable to execute stored instructions to plan the route by:
assigning respective costs to traversing sensed features in the environment, including the terrain or obstacle classified as deformable; and
determining, based on the assigned costs, a route through the environment.