Zero Based Timetabling Project (ZBTT)

The Indian Railways has been planning to undergo a revamp of train timetables to rationalize trains, halts across all routes. Though this was initiated in June 2019, IIT Bombay was asked to take this activity up in December 2019. In particular, our team is handling the ZBTT for 6 major routes: the so-called golden quadrilateral + diagonals (GQD). (The vertices of the quadrilateral are Delhi/Howrah/Mumbai/Chennai.)

This task is acknowledged to be a mammoth task given the number of trains, the volume of infrastructural details, the heterogeneity in the trains/sections. Below are some exact numbers.

Infrastructural details:

Distances route-wise:
  • Route-1: NDLS-MMCT: 1382.0km
  • Route-2: NDLS-MAS : 2179.8km
  • Route-3: HWH-MAS : 1659.3km
  • Route-4: HWH-CSMT : 1969.8km
  • Route-5: MAS-CSMT : 1276.8km
  • Route-6: NDLS-HWH : 1445.7km
Number of Zone-Railways (ZRs) involved in the GQD: 12
(few of them are in 3 GQD routes, many of them in 2 routes, and some of them are involved in just one route.)

Portions of the route that are common significantly across multiple routes (and hence need a joint allocation of infrastructural resources):

(At each node of the quadrilateral, 2 routes have an overlap, further, the two diagonals also have an overlap over the NGP-SEG portion.)

Trains related: (in first iteration)
  • 3510: total number of trains provided to IITB for scheduling across the 6 GQD routes.
Simulated in first iteration:
  • 1650: number of daily-paths scheduled:
  • 1325: daily-trains (within 1650 paths)
  • 335: daily-paths for non-daily trains: one daily-path per group of non-daily trains that avail the same path (within the 1650 paths)
  • 897: number of non-daily trains that got scheduled by a daily-path (these 897 get mapped to 335 daily-paths)
Jumping-route trains:
  • 726: number of daily trains that "jump" routes: (includes reversals (for e.g. at KGP), but except: VSKP. Visakhapatnam-reversal NOT counted within 726 count above as "reversal")
Trains removed (within the simulation exercise):
  • 467: single-touch trains (at terminal stations ONLY, or passing through KOTA, for e.g.)
  • 818: Removed for other reasons:
    • mostly: brief-touch trains (for 4 stations or less),
    • but some also because they run on EXTRA parallel infrastructure and ZR can schedule themselves: small number of such trains)

This work is ongoing and partial delivery of the timetables has happened and feedback is being incorporated into the generated timetables.

Below are some news links (and pdf-files corresponding to these articles, just in case the news-links do not work for any reason.)

Faculty members involved with this project are Profs. Narayan Rangaraj (IEOR), Shiva Gopalakrishnan (ME), Kumar Appaiah (EE) and Madhu Belur (EE). Students/project-employees involved in this are: P. Sudarshan, I. Sidhartha Kumar, Chandrashekhar Bobade, Satwik R. V., Bhushan Deo, Akshay Bajpai, Soham Naha, Omkar Karmarkar, Mitul Tyagi, Tushar Pant, Sandeep Kumar, Sunil Kahalekar, Abhishek Panigrahi, Alok Srivastava, Manish Shukla, Samruddhi Pai, Akshay Upasany, Kunal Apoorv, Akash Chavan, Saloni Shah. Due to the lockdown situation in India/Mumbai/IIT-campus since mid-March 2020, the entire effort was by careful coordination from across India: Nainital, Rourkela, Ajmer, Pune, Chennai, Howrah, Gandhinagar, Bhubaneswar, Thirupur, Nanded, Virar, Kozhikode, Aurangabad, Delhi, Mumbai, where the contributors were living during the months March-July 2020.

Contact persons

Prof. Narayan Rangaraj,
Industrial Engineering and Operations Research (IEOR),
IIT Bombay, Powai, Mumbai 400 076
narayan.rangaraj[AT]iitb.ac.in

and/or:

Prof. Madhu N. Belur,
Department of Electrical Engineering,
IIT Bombay, Powai, Mumbai 400 076
belur[AT]iitb.ac.in

Last modified: 24th April 2024