The APB resulted from an across-the-fence discussion between an Air Canada pilot and his next-door neighbour, Indal president Vince Lacey.
Indal began working on an APB system in 2002, which resulted in the prototype now in use at Pearson.
The markers are installed according to a template, so that the APB will accurately mate to any aircraft.
Safety features include a two-element collision avoidance system: pressure-sensitive pods in the bridge stairs and wire loops around the bogie wheels that sense obstructions and stop the APB.
The APB system interfaces with any type of bridge or manufacturer, says Upp.
As the APB system is PC-based, it can interface with an airport's existing network, and be installed so that airport personnel can dial remotely into the system for maintenance states.