Train Collision Avoidance System (LKAVACH)

Presentation

LOCO KAVACH

S.Upendra Chary (ITD-3)

Train Collision Avoidance System (LKAVACH)
Presentation
Train Collision Avoidance System (KAVACH)
Train Collision Avoidance System (LKAVACH)
Presentation
 Train Collision Avoidance System (KAVACH)

Locomotives were classified by track gauge, motive power, function

and power (or model number) in a four- or five-letter code. The first
letter denotes the track gauge.
...
Syntax
1.First letter (gauge): W – Broad gauge (wide) – 5 ft 6 in (1,676 mm)
2.Second letter (motive power): D – Diesel. ...
3.Third letter (job type): G – Goods.
Train Collision Avoidance System (KAVACH)
 Train Collision Avoidance System (KAVACH)

• Locomotives in production today generally have either four or six

axles, each powered by an electric traction motor.
• Their wheel arrangements are expressed as Bo-Bo, with B
indicating a two-axle truck that is powered, or Co-Co, with C
meaning a truck with three powered axles.
• The Indian locomotive class WAG-9 is a class of 25 kV AC
electric locomotives. The model name stands for broad gauge
(W), AC Current (A), Goods traffic (G), 9th generation (9)
locomotive.
Train Collision Avoidance System (KAVACH)
Train Collision Avoidance System (KAVACH)

Locomotive
 Train Collision Avoidance System (KAVACH)

• Commonly used braking systems is IRAB1

that's stands for Indian Railway Air Brake
System.
• Basically 5 Kg/cm² pressure is required for this.
• Now we have CCB (Computer Controlled
Brake System) in modern locomotives.
 Train Collision Avoidance System (KAVACH)

1.Dynamic brakes- rheostatic type and

regenerative type . They are just to slow down
the train . They work on electromagnetic
induction laws.
2.Service brakes- Pneumatic , Electropneumatic
and Vacuum brakes. They are used to stop the
train in service and in emergency.
3.Mechanical Brakes- these are purely
mechanical linkage type brakes generally used
as parking brakes and a backup brake system
if all brake systems fail.
Train Collision Avoidance System (KAVACH)
Train Collision Avoidance System (KAVACH)
 Train Collision Avoidance System (KAVACH)

• KAVACH is an automated situational awareness system that

provides Automated Train Protection as well as Collision
Prevention capabilities for trains.

• Prevents Signal Passing At Danger (SPAD) and enforces

automated speed restrictions wherever required

• Detects and automatically stops trains in situations of head-on,

rear-end and side-ways collision

• Provides in-cab display of signaling to the loco pilot, making train

operation through fog possible
 Train Collision Avoidance System (KAVACH)
 Prevention of signal passing at danger (SPAD)
 Cab Singnaling, loop line speed control
 Prevention of over-speed: section speed, train speed, PSR
 Protection of roll back and reverse movements
 Prevention of side-collision in block section
 Prevention of head-on and rear end collisions
 LC gate automatic warning
 SoS messages
 Computation of train length
 Shunt limits validation
 Centralized live monitoring of train movements in NMS
Train Collision Avoidance System (KAVACH)

• Movement Authority
The distance upto which the
train is permitted to travel
safely

• End of Authority (EOA)

Location up to which the
train is permitted to
proceed and where target
speed should be zero
KAVACH – System Architecture
 ®

Kavach Architecture

KAVACH
LOCO KAVACH EQUIPMENTS Sub-System
On-Board Sub-Systems (LKAVACH)

The On-board subsystem shall be composed of

• Loco KAVACH Vital Computer

• RFID reader
• Pulse Generator.
• Loco KAVACH Radio Unit
• Driver Machine Interface (DMI)
• Brake Interface Unit (BIU), where required
On-Board Sub-Systems (LKAVACH)
Pulse Generator

• The Speed Sensor is mounted on

the axle of the locomotives
• Based on the wheel diameter
(configurable) and number of
rotations per second, the speed
will be calculated
• The speed sensor also has the
ability to give the direction of the
locomotive
• The speed sensor has
redundancy built into it
KAVACH – RFID Tag Reader

• A fixed information is programmed in a

RFID Tag and is mounted on a rail
sleeper
• RFID Reader is mounted under the
Locomotive (Adjustable Bracket)
• The reader excites the tag(s) and receives
the fixed information programmed in it
• The location information of the train is
identified based on the decoded tag
information
• This location data is transmitted to the
Station TCAS system and the same is
used to update the MA
RFID Reader
 KAVACH – RFID Tag Reader

The RFID reader antenna shall be able to read the RFID tag
from a vertical distance of 700mm from the bottom of the
RFID reader antenna to the top of the rail level.

The RFID reader antenna would be installed so that the

vertical distance from the bottom of the RFID reader antenna
to the top of the rail level is 450mm +/- 50mm. The lateral
center of the RFID reader antenna shall be within +/- 50mm
of the track center with antennae in the horizontal plane.

READER and its power supply modules are enclosed IP65

enclosures to protect from Dust and Damage
 KAVACH – Loco Brake Interface Unit

• Indian Railways locomotives use three types

of braking systems.
• Indian Railways Air Brake (IRAB)
• CCB (computer controlled Braking) by
Knorr Bremse and

• E-70 by Faively Transport

KAVACH BRAKE INTERFACE
 KAVACH BRAKE INTERFACE
• BIU shall apply normal, service & emergency brakes of
locomotives respectively based on the type of brake
command received from Loco KAVACH unit. In addition to
these brakes, it shall also apply Loco brake, if Loco Brake
command is generated by Loco KAVACH.
BIU consists of two modules:
Electronic Module:
• It consists of a Control Card having built-in air brake control
logic. Control Card interfaces with Analog Input Module,
Digital Input Module & Digital Output Module to monitor
and control air brake application/release.
Pneumatic Panel:
• It consists of different valves, pressure transducers and
manual cocks-Interfaced with IRAB system & Electronic
Module for brake control purpose
 KAVACH BRAKE INTERFACE

Working of BIU
• KAVACH identifies the braking requirement.
• KAVACH communicates braking signal(s) to BIU.
• BIU communicates signals to the existing brake
system of locomotive
• BIU communicates signal for cutting off traction of
locomotive
• BIU generates audio-visual indication for Loco Pilot
• BIU gives status of execution of braking command to
KAVACH.
 KAVACH BRAKE INTERFACE

Features of BIU
• BIU works parallel to Locomotive Brake System.
• Does not affect brake characteristics of
locomotive/train.
• Can override the Loco Pilot Braking and Vice-Versa-
Higher braking prevails.
• BIU initiated braking cannot be reduced by Loco Pilot.
• Manual and automatic isolation possible.
 KAVACH BRAKE INTERFACE

Fail safety
• Loss of electric power leads to Automatic Emergency Brake
• Loss of communication between Loco TCAS unit and BIU results
in Automatic Emergency Brake
• For any brake application Traction power is cut off.
• the loco unit shall be able to stop the train short of a safe distance
or control the speed to the desired value before the target.
• This distance should be possible to be configured during
installation with nominal values as 100m for Rear-end Collision
prevention, 300m for Head-on Collision prevention, and short of
Signal at Danger in case of SPAD prevention
 KAVACH BRAKE INTERFACE
• By pressing Manual Brake Test (MBT) button by the Loco Pilot in
stationary condition of the train, working of all brake valves of
Brake Interface Unit (BIU) can be tested.
• The braking logic of the Loco unit shall be so intelligent that based
on the
(i) brake characteristics of the train,
(ii) speed of the train and
(iii) gradient of the location & the target,
Loco unit shall decide which type(s) of brake and when to be applied
to stop the train short of safe distance or control the speed to
desired value before target without frequent repeated braking
 ®
TRAIN SPEED MORE THAN PERMITTERD SPEED

. If Train speed is above permitted speed limit by 2 KMPH,

Over speed alarm will be issued.

 If Train speed is above permitted speed limit by 5 KMPH,

Normal service brake will be applied.

 If Train speed is above permitted speed limit by 7 KMPH,

Full service brake will be applied.

 If Train speed is above permitted speed limit by 9 KMPH,

an Emergency brake will be applied
 ®
KAVACH – Driver Machine Interface (DMI)
Also called as LP-OCIP (Loco Pilot Operation cum Indication Panel)

• Complies with IRDMI specification, to

provide a standard user interface to
KAVACH.
• 10.4” Color LCD Display, with 10 soft
keys.
• Allows Loco Pilot to define
• whether the loco is leading or
non-leading
• If the loco is operating as a light
engine or as part of a train
formation
• Allows the loco pilot to generate an
SoS message in an emergency
situation
 ®
Train Collision Avoidance System (KAVACH) LP-OCIP
 ®

Indications and switches on DMI

 ®

LOCO PILOT ACKNOWLEDGEMENTS

Loco Pilot needs to acknowledge the System prompts by

pressing the Ack/Common push button on the DMI in the
following situations.
a) Transition from FS mode to LS mode due to radio
communication failure. To be acknowledged within 15 sec,
otherwise system will apply service brakes.
b) Transition from LS mode to SR mode due to radio
communication failure. To be acknowledged within 15 sec,
otherwise system will apply service brakes.
c) When exits from KAVACH territory. To be acknowledged
within 15 sec, otherwise system will apply service brakes.
d) When Train is stopped in Intermediate Block Section (IBS)
during normal operation. To be acknowledged within
15 sec, otherwise system will generate SOS.
 SOS CONDITIONS

• Loco KAVACH shall have a provision to generate Manual and

Station KAVACH shall have provision to generate SOS
• SOS shall be received to all Loco KAVACH within a 3000 mts
radius of the vicinity
• SOS received Loco KAVACH can move with a speed of
30kmph after receiving SOS with EB Brake application by
pressing Cancel Button on DMI
• SOS shall be cleared by pressing CANCEL Button by the
source who is generating
• SOS shall be cleared in other Loco KAVACH moving away
from source 1500mts
• No communication from source for a period of 3 minutes
RADIO MODEM

Working frequency : 406 - 470 MHz

UHF
Channel Bandwidth : 25KHz
SET UP port – Diagnosis
DATA port - communication
Mode of operation : Full-Duplex
Data rate : 19200bps over-the-air;
Output Power : 10W
Power Supply: 24V
Two radio modems are used for
redundancy
LOCO Radio Antenna
 GPS Antenna

• GPS antenna is installed on top of the station

building and Loco connected to the station
KAVACH.
• Accuracy of Time Pulse : 1PPS
• Used for time synchronization of TCAS Radio
communication network
• Real time events logging
• Two GPS modems are used for redundancy
• Both GPS are active. Faulty one is detected and
isolated in 3 cycles.
• Automatic recovery of faulty GPS
.
Network Monitoring System – Block Diagram
Railnet/Internet
GSM
Network
Loco 1
Web
Reports

Loco 2 Loco 3 Network

Monitoring
System
Web
Reports
E1 on OFC

Station A Station B Station C Station N

Nov 2021 Kavach from Kernex 54

 Network Monitoring System

• Network Management System (NMS) shall be provided over

OFC Network (E1 interface) for centralized monitoring of
Kavach equipped Trains and Stations within the network.
• It is used for troubleshooting of error events, off line
simulation, real time monitoring of loco Kavach etc.
• Stationary Kavach and Loco Kavach transmit exceptional
fault/critical messages to NMS.
• A Central Server is present in the Division Control Room.
• All relay information and radio packets exchanged between
Station and Loco are logged in Central Server and accessed
through NMS.
KMS & NMS PROCESS
 Key Management Server (KMS) is designed to share secret
Authentication keys to Stationary and Loco Kavach units.
Message origin authentication/message integrity is a safety procedure
ensuring the integrity and authenticity of messages during Radio
communication.
These Authentication keys are used to protect the messages against
modification and to ensure that no one can masquerade as the originator
of the message.
They are shared only after authenticating the Loco Kavach through OTP.
KMS is deployed on a secured server on the Internet.
All the Loco Kavach units request for the Authentication keys
periodically and use the same for Radio Communication.
GSM modules residing in the Event Logger module are used to connect
Loco Kavach to GPRS (Internet).
 Loco KAVACH Unit
• Loco KAVACH unit is the heart of the
KAVACH system in the loco.

• It interfaces with
• LP-OCIP (DMI) to facilitate
interaction by the loco pilot
with KAVACH
• Brake Interface Unit (BIU) to stop
the train when needed and
 ®
Train Collision Avoidance System (KAVACH)
 ®
Train Collision Avoidance System (KAVACH)
 LOCO KAVACH INPUTS & OUTPUTS
LOCO INPUTS LOCO OUTPUTS
• COMMON • TCAS OK
• SOS • TCAS NOT OK
• CANCEL
• SOS
• LEADING
• BUZZER
• NON LEADING
• CAB1 • HORN
• CAB2 • NORMAL BRAKE
• RUN FORWARD • FULL SERVICE BRAKE
• RUN REVERSE • EMERGENCY BRAKE
• BP COCK
• SOS COUNTER
• MR COCK
• TRIP COUNTER
• BIU NORMAL - ISOLATION
• ISOLATION COUNTER
Loco TCAS architecture
KAVACH – System Architecture
KAVACH – System Architecture
 KAVACH – System Architecture

GPS & GSM

ANTENNA

Stationary TCAS sends: Point/Switch status

Static Section Profile STATION
SIM
OCP
Movement Authority
TCS
CONTROL
Track occupancy status
UNIT
Signal informattion
wrt to Loco TCAS location
(every 2 sec) STATION
RF ANTENNA

Location
Track Identification No
Direction - Normal/ reverse
Speed
Train Length
(every 2 sec)
RF, GPS & GSM
ANTENNA

SIGNAL
ASPECT RELAYS
BRAKE ONBOARD LP
INTERFACE UNIT COMPUTER OCIP

RFID TAGS
 KAVACH – System Components

W S
A I
Y D
- E
RFID Tags GPS antenna Radios

L Speedo meter
O O
C
Loco Vital Computer Driver Machine RFID Reader Radios
Interface Brake Interface Unit
TYPE OF DATA Awareness received
INPUT

Communi RF Communication from Signal Aspects,

cation Station to Loco Movement Authority,
Permitted Speed
RF Communication from Loco Position and speed
to Station information of train

GPS Synchronized time and

train position data

GSM Data communication to

Network Management
System (NMS)
SUBJECT IRISET- SECUNDERABAD 71
 ®

Capacity and Performance of the System

The Stationary TCAS system is capable of handling 50

units of Loco TCAS systems in its station vicinity.

The Stationary TCAS can maintain Radio communication

with all these 50 units and control the movement.

In the Block-section, the Loco TCAS is capable of

handling (4) four locos with Loco TCAS systems.

The Loco TCAS system can handle Radio

communication with other Loco TCAS units and control
the movement.
KAVACH – Loco Brake Interface Unit
 LOCO KAVACH COUNTERS

Three Electromechanical non-resettable 6-digit counters are

provided inside the Loco TCAS Electronic unit to record the
following operations:

a) Isolation Mode Counter: This counter will be

incremented, whenever Isolation mode is selected.

b) Trip/Override Mode Counter: This counter will be

incremented, whenever Loco TCAS enters to Trip mode or
Override mode is selected by the Loco Pilot.

c) SOS Counter: This counter will be incremented, whenever

SOS message is transmitted to other Loco TCAS units or SOS
message is received form stationary TCAS units/Loco
TCAS units.
RFID Tag Fixing Arrangement
• RFID Tags provided in block section at ~1 km
and in station yard for each signal and signal
approach.
• Used for track identification, correction of
location of train and train movement direction
identification.
Tags Placement

• Fixed at the center of PSC Sleepers

• No holes are drilled in the Sleepers.
Fixing through clamps only
• Not more than 75mm above the top
surface of PSC Sleeper at center.
• Suitable for reliable working at train
speed upto 200 KMPH
• able to work even when submerged in
water up to rail level
 Serial Communication
• RS-485 communication from KAVACH sub-system to LP-OCIP
unit
• RS-485 communication from KAVACH sub-system to the RFID
reader
• RS-485 communication for BIU
• RS-232 communication from KAVACH sub-system to Optical
modem for Radio communication.
Ethernet Communication
• IB-HUT KAVACH communication channel is connected to
Ethernet switch from Integrated Data Logger
• OFC-Hut communication is connected to Ethernet switch
from Integrated Data Logger
• Lap-top interface to Integrated Data Logger (IDL) card
 Serial Communication

• RS232 is more than able to perform for a short distance

and low data speed requirements.

• RS232 has a transmission speed of 1Mb/s up to 15M

.
• RS485 has a data transmission speed of up to 10Mb/s for a
distance of 15M. At the maximum of 1200M, RS485
transmits at 100Kb/s.
Loco Operating Modes