Anti collision devices (ACD)

1. Seminar
at the
topic of
Anti Collision Devices
(ACD)
Submitted By: Tarun Khaneja
Roll no : 2110045
Contact no : 09034406598

2. Accident (Collision)

4. Anti Collision Device
(ACD)
The ACD Network is a Train Collision prevention system
invented by Rajaram Bojji .

5. Overview
 They take inputs from GPS satellite system for
position update and for exchanging information .
 ACDs fitted both in Locomotive and Guard's Van of
a train.
 ACD’S act as a watchdog in the dark as they
constantly remain in lookout for other train bound
ACDs .
 They communicate through their radios and identify
each other. If they happen to find themselves on
the same track and coming closer to each other,
they automatically restrain and stop each other.

6.  Loco ACD of a train also applies brakes to reduce
the train speed either to 15 km/h.
 or to bring the train to a stop if train bound ACDs of
other train are radiating 'train parted' message.

7. Unit for Locomotive
 ( L 435 x W 203 x H 342 mm )

8. Working of ACD
 ‘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).

9.  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’.

10. ‘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.

11. Benefits of the ACD system
1. Very economical and cost effective.
2. Easily adaptable and expandable.
3. Does not degrade the existing safety level.
4. Employs state-of-art hardware and software
technology.
5. No way had side equipment required, hence no
requirement of Power.
6. No cabling on the track required (which is more
expensive and cumbersome).
7. Less susceptible to Vandalism.
8. It does not require any inputs to be fed by the crew
at the start of journey, thus human error is
eliminated.

12. 9. Maintenance Support System (MSS) daily Reports
of incidences of Warning to the Driver due to Gate
OPEN or Obstruction.
10. Date wise Report of incidences of Warning to the
Driver due to Gate OPEN or Obstruction.
11. Daily Maintenance Report “ Failure of Loco
Unit and Gate Unit.
12. Date wise Maintenance Report “ Failure of
Loco Unit and Gate Unit.

14. Applications
 ACDs can be implemented in railways to prevent
collisions and to decrease the timing between two
consecutive trains running one after another.
 It can be used in heavy vehicles like cranes,
earthmovers etc to prevent accidents and for their
safe working in public places.
 ACDs can be used as a tracking device.