COMPASS, also referred to as Freeway Traffic Management System, is a system run by the Ministry of Transportation of Ontario (MTO) to regulate the flow of traffic on the 400-series highways

400-series highways

The 400-series highways are a network of controlled-access highways throughout the southern portion of the Canadian province of Ontario, forming a special subset of the provincial highway system. They are analogous to the Interstate Highway System in the United States or the British Motorway...

. COMPASS-enabled highways include Highway 401, one of the highest-volume highways in the world, as well as the Queen Elizabeth Way

Queen Elizabeth Way

The Queen Elizabeth Way, commonly abbreviated as the QEW, is a 400-Series highway in the Canadian province of Ontario. The freeway links Buffalo, New York and the Niagara Peninsula with Toronto. It begins at the Peace Bridge in Fort Erie and travels around the western shore of Lake Ontario, ending...

 (QEW), Highway 402, Highway 403, Highway 404, Highway 405, Highway 410, Highway 409, Highway 417 (the Queensway), Highway 427 and Thorold Stone Road.

COMPASS uses pairs of in-road sensors to detect the speed and density of traffic flow. This data is fed to a central computer at the MTO Downsview office and analyzed by operators, who also view the feeds of traffic cameras placed along the highways. Changeable Message Signs (CMS) then display messages to motorists on the highways, advising them of upcoming collisions, closures, detours

Emergency Detour Route

The Emergency Detour Routes, originally Emergency Diversion Routes , are a system of temporary detour routes paralleling many major highways in Ontario. Most of these follow county or municipal roads within the province that are not provincially-controlled...

 and traffic flow.

Algorithms

The primary algorithm used by the Ministry is known as the McMaster algorithm, designed by Professor Fred Hall of McMaster University

McMaster University

McMaster University is a public research university whose main campus is located in Hamilton, Ontario, Canada. The main campus is located on of land in the residential neighbourhood of Westdale, adjacent to Hamilton's Royal Botanical Gardens...

, in Hamilton, Ontario. Incident Detection algorithms have also been widely used throughout the COMPASS-enabled area.

Research on new algorithm developments and evaluations is performed at the ITS Centre and Testbed (ICAT), at the Civil Engineering department of the University of Toronto

University of Toronto

The University of Toronto is a public research university in Toronto, Ontario, Canada, situated on the grounds that surround Queen's Park. It was founded by royal charter in 1827 as King's College, the first institution of higher learning in Upper Canada...

. The ICAT is equipped with direct fibre-optic links to the Ministry of Transportation, and received both traffic camera and loop detector data on a live basis. Visual data can be used to confirm the presence of incidents detected by the various algorithms.

COMPASS cameras

Sections with COMPASS cameras:

• QEW from Highway 427 to 50 Rd (Toronto to Stoney Creek)
• QEW from 7th Street to Mountain Road (St. Catharines to Niagara Falls)
• QEW from Thompson Rd to Bowen Rd (Fort Erie)
• Highway 400 from south of 401 to Langstaff Road (Toronto-Vaughan)
• Highway 401 from near Highway 410 to near Harwood Avenue (Mississauga-Ajax)
• Highway 401 from near Wellington Road South to near Old Victoria Road South in (London, Ontario)
• Highway 402 from Mandaumin Road to Front Street North (Sarnia)
• Highway 403 from Highway 401 to QEW (Mississauga-Oakville)
• Highway 403 from QEW to west of King Road (Burlington)
• Highway 404 from Highway 401/Don Valley Parkway to Steeles Ave (Toronto-Markham)
• Highway 405 from QEW to Queenston-Lewiston Bridge (St. Catharines-Niagara On The Lake)
• Highway 406 from near Third Avenue to QEW
• Highway 409 from Highway 401 to Martin Grove Road (Toronto)
• Highway 410 from Courtneypark Road to Highway 401 (Peel Region)
• Highway 417 from Ottawa Road 174 to 416/Richmond Road (Ottawa Region)
• Highway 427 from Gardiner Expressway/QEW to Finch Avenue (Toronto-York Region)
• Highway 58 from Pine Street to Thorold Stone Road (including Thorold Tunnel) (Thorold)

False alarms

A false alarm for incident detection is not only highly undesirable, but seriously damages the confidence in the detection system. Therefore, a near 100% alarm accuracy is needed. This does not mean that 100% traffic parameter accuracy is required from the traffic sensors; however, the logical commands that analyze the change in traffic parameters need to be selected carefully in order to minimize the probability of false alarms yet detect all major incidents as well as a high percentage of all other incidents. Most importantly, confirmation of incident and evaluation of incident type by manual inspection of a video camera screen is probably the most significant incident detection technique.

See also

• Electronic Monitoring and Advisory System
  Electronic Monitoring and Advisory System
  The Expressway Monitoring and Advisory System , also known by its acronym of EMAS, is a computerised system that is used to monitor traffic on Singapore's expressways. EMAS enables Land Transport Authority personnel to detect accidents and respond to them more quickly...
  
   - a similar type of system in Singapore
• Motorway Incident Detection and Automatic Signalling
  Motorway Incident Detection and Automatic Signalling
  Motorway Incident Detection and Automatic Signalling, usually abbreviated to MIDAS, is a distributed network of traffic sensors, mainly inductive loops, which are designed to set variable message signs and advisory speed limits with little human intervention...