Dublin City Council vision for Dublin is to make it a city where people of all ages and abilities have the confidence, incentive and facilities to cycle. Numerous on road cycle lanes have been incorporated into designs for Quality Bus Corridors (QBCs) as well as a mix of on road and off road cycle routes. However, in 2010 Dublin City Council, with funding from the Department of Transport, began work on a new way of providing cycle facilities.
The Canal Way cycle route is an ambitious plan to provide an off road, mainly segregated 2 way Cycle Route, along the two canals which encircle the center of Dublin. The Royal Canal on the Northside of the Liffey and the Grand Canal on the South with the link between the two being the iconic Samuel Beckett Bridge.
3.6 km of phase 1 of the project was opened in 2012 with phases 2 and 3 now moving from design to Construction over 2014. These canals stretches a combined distance of 275kms from Dublin through the midlands of Ireland to the Shannon river, and some cycle routes have already been provided along the length of the canals with more in design.
The requirements to treat the route as a separate traffic route along its length and not share its facilities with any existing traffic signals upgraded with separate bicycle detection at each junction. As a sign of this, no cyclist buttons are used along its length. Instead loop detection and stop-line Video detection are used. Each junction was equipped with dedicated Bicycle detection at traffic signals, separate phases for bicycles with 100 mm cycle heads and with a new type of signaling to resolve bicycle and pedestrian interaction at traffic signals along the route. At each junction, CCTV was to be provided, to allow traffic management, as well as to provide an element of security. All DCC Traffic cameras are shared in real time with the Irish Police.
Along much of the route the Canal Way is located on the canal side, which required the provision of a boardwalk cantilevered over part of the canal to avoid cycle/pedestrian shared space.
The primary objective of the design was to ensure that cyclists would be treated in the same manner as road traffic (cars and trucks), by providing dedicated cycle phases in the traffic signal sequence or in other words Toucan crossings would not be used.
At each crossing point, the cycle way was provided with dedicated 100 mm signals and in many cases, due to space constraints, the primary signal for the adjacent traffic lane was mounted on a Cantilever pole in addition to highlight the separate nature of the route Stainless steel Traffic Signal poles were used for the Cycle track arms of the junction only.
Dublin uses the Australian SCATS Adaptive traffic control system on dedicated fiber optic network around the City with multiple separate rings radiating from the Traffic Control Centre in the City Centre. In total in phase 1, 22 junctions or pedestrian controllers were connected to this fiber network along with 16 cameras.
Most of the 240 Traffic cameras which DCC Traffic use are analogue with multiple fiber optic networks providing the main communication network for both CCTV and Traffic Controller Communications. At the traffic center the CCTV signals are split with one input going into an analogue matrix and the other being converted into an IP stream for the Secondary Digital IP matrix. This provides maximum flexibility for distribution while ensuring that the CCTV images are available at the in-station without any compression loss and simplifying network security issues by not providing IP access points at the field equipment.
The solution
The solution chosen was the
AMG 3700 series, configured in an 8 channel drop and insert configuration over a single fiber providing 8 insert points along the route and providing a single CCTV input, plus a bidirectional data channel configured for RS232.
The RS232 is connected directly to the Traffic controllers on the SCATS AUTC system and at the in-station, this allows connection to the SCATS Hardware via DIGI C/Con 16 multi-channel serial adaptors. Because the system provides a point-to-point channel at each location, the in-station provides 8 separate bidirectional channels with RS 232 interfaces. Enabling the Traffic controller and the CCTV to be brought back on the same system, maximizes its effectiveness. In addition, a 100 Mbits Ethernet connection is available at each node for future use. The 3700 also provides a CWDM transmission solution which allows up to 72 analogue cameras to be collected onto a single fiber. The dual redundancy means that in case of a fiber failure or node failure, the system will immediately re-route and maintain operation. The Network Management system reports fiber failures and node failures immediate via SNMP directly into the DCC Fault Management System.
The 3700 series provides zero control latency and uncompressed digital transmission thus ensuring the image received at the Traffic Control center can be used for multiple applications including video analysis.
Three 8 channel 3700 receivers were used at DCC Traffic Centre, with provision for more to be added as required, and only three fiber cores of the fiber laid along the length of the cycle route was utilized to provide connectivity for up to 24 Cameras and 24 ( or 48 ) Traffic Controllers depending on board type.