Navigation Innovations

The majority of our automatic guided vehicles (AGVs) use laser triangulation as the primary form of navigation. Each vehicle has one (or more) rotating laser sensors that interact with targets (reflective strips of tape) mounted along the path. The laser sensors receive the reflected signals and use that data to triangulate the vehicle’s exact position. Our navigation algorithms recalculate the vehicle position 40 times per second, keeping heading corrections small and vehicle operation smooth. Laser triangulation allows very accurate vehicle positioning with flexible, virtual guide paths that are created and changed in Layout Wizard software.

A growing number of our AGVs use natural environment as a primary or secondary form of navigation. Raw data is collected by the obstacle detection laser sensors, creating a map of the environment where the AGV will operate.

Any temporary features that are sensed in the environment can be removed from the map and the remaining features (walls, columns, equipment, etc.) are used for navigation. As the AGVs operate, navigation algorithms compare the current array of features with those stored in the baseline map. Natural environment navigation is best used in controlled environments and for specific applications such as deep lane storage, trailer loading, and product staging.

When laser triangulation or natural environment navigation cannot be used, inertial guidance offers an alternative.  A high precision gyroscope provides feedback on vehicle heading and a series of small magnets are sealed into holes drilled in the floor.  A sensor detects the position of each magnet as the vehicle passes over it and the vehicle corrects to stay properly positioned over the magnets.  Magnets are typically spaced a few meters apart all along the guide path.

Occasionally found in special applications but frequently in older legacy installations, wire guidance was a primary form of vehicle guidance in AGVs before 2000.  An antenna mounted under the vehicle tracks a wire which is embedded in the floor. The wire must be installed along the entire road system and must be moved and reinstalled when introducing path changes.

Used in specialty applications, optical guidance uses sensors which follow multi-colored tape that is applied to the floor.

Similar to inertial without the gyroscope heading sensor.  A series of magnets installed in the floor along the path provide feedback to the AGV.  Without the heading gyroscope, the magnets typically have to be spaced more frequently.  Spot navigation is typically a supplemental navigation used in combination with other forms for small sections of the system where the primary form of navigation is not available.

Similar to wire guidance, except magnetic tape is adhered to the floor to define the guide path. The vehicle follows the contour of the tape using an antenna. Path changes are introduced by removing and reinstalling the tape.