Anti-Collision Device (ACD) Network’ - A Train Collision Prevention
System (TCPS)
Safety violations due to ‘human errors or limitations’ and ‘equipment failures’
occasionally result in Train collisions. Patented by Konkan Railway Corporation, ‘AntiCollision Device Network’ (also called ‘Raksha KavachTM’, meaning ‘A Train Safety
Shield’)...
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is an on-board train collision prevention system.
Designed as a ‘non-signal’ system, it provides ‘non-vital’ ‘safety enhancement’
layer over the existing safety systems of train operations. ‘ACD Network’ therefore fills up
‘safety gaps’ left out due to limitations of existing ‘signal’ based train protection systems.
‘ACD Network’ consists of mobile ACDs (on Locomotives and Guard’s Brake
Vans) and trackside ACDs (at Stations, Level Crossings, Locosheds, Sensors based and
Repeaters, en-route). Mobile ACDs take inputs from GPS satellite system for position
updates and network with track-side ACDs located within a radius of Three Kms (using
UHF radio modems); to activate brake(s) with the help of on-board Loco ACD(s) through
their Automatic Braking Units (ABUs), whenever a collision-like situation is ‘perceived’.
‘ACD Network’ is likely to prevent ‘head-on’ and ‘rear-end’ collisions in mid-sections,
collisions at ‘high speed’ in ‘station area’, ‘side collisions’ with derailed vehicles
obstructing adjacent line, collisions due to ‘train parting / jumbling’ and collisions with
‘road vehicles’ at level crossing through ‘Train Approach’ warning and detection of ‘Gate
Open’. Loco ACDs also give ‘Station Approach’ warning to drivers. Moreover, using
Manual ‘SOS’ buttons on their ACDs, Drivers, Guards and Station Masters can also ‘stop’
trains when any unusual is detected.
A ‘pilot’ project of provision of ACDs on 1736 Kms of Broad Gauge route of
Northeast Frontier Rly zone of Indian Railways has been declared as commissioned by
Ministry of Railways (Railway Board) in June 2007
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