On 8/12/22 20:15, Mal Rowe wrote:
>

> Melbourne anticipated switching over to GPS to keep track of where

> their trams were - and all the new deliveries came fitted with the

> equipment.

>

> As I understand it the GPS (satellite based) was not able to reliably

> determine whether a tram was in Collins St of Bourke St, so the old

> AVM system lives on.

>

Which is why many of the robotic platforms my employers have built have
aircraft IMUs (Inertial Measurement Unit) in them for accurate
augmenting of GPS location tracking.

Unfortunately such devices are considered weapons components (missile
guidance systems) and we had to get US state department approval for
every such device imported.