Picture hundreds of fully autonomous airplanes trying to take-off and land in a small airport with just a handful of terminals. Each plane is assigned to pick up and drop off passengers in a precise location within a narrow window of time while minimizing the distance traveled on the tarmac and between terminals.
Similarly, the Symbotic System’s autonomous bots must navigate a shared space called the transfer deck, with its driveways and aisles, to pick up and deliver cases within the high-density structure. A proprietary routing algorithm enables hundreds of bots, moving at up to twenty-plus miles per hour, to do this quickly and efficiently without colliding or delaying other bots while executing assignments.
The routing algorithm calculates an optimal path for each robot to maximize overall system efficiency and minimize stop-and-go actions that create energy loss and excess wear on the robot.
The routing algorithm works in conjunction with a case allocation algorithm. Together they consider the location of every case, product expiration dates, and timing and sequencing of the order, as well as numerous other factors that impact picking efficiency, including robot travel time and distance, traffic patterns, and congestion in aisles and driveways.
The routing algorithm explores all possible route combinations for each robot, and orchestrates the entire fleet of bots in parallel. It assigns each bot to execute a pick/place action based on the most optimal route, eliminating those that conflict with other bots or sub-optimize the system overall. And it does all this in real-time via low latency communications so the bots can execute their tasks with industry-leading speed.
The algorithm orchestrates the work so that the autonomous bots appear to effortlessly avoid hitting one another and the whole thing looks like a choreographed dance. This is the leading edge of temporal spatial reservation and combinatorial optimization.
The routing algorithm is one of the core technology advancements that unlock future productivity improvements for the mobile robots and the Symbotic System overall.
Symbotic’s routing algorithm has already enabled 20-25% productivity improvement in the system to date. Further improvements will allow customers to increase throughput capacity. And Symbotic engineers continue to push the boundaries of what is possible.