wltp gear-shifts calculator

Development Status Integration-build status cover-status Documentation status Latest Version in PyPI Downloads Issues count

PyPI repo:https://pypi.python.org/pypi/wltp
Keywords:UNECE, automotive, car, cars, driving, engine, fuel-consumption, gears, gearshifs, rpm, simulation, simulator, standard, vehicle, vehicles, wltc
Copyright:2013-2014 European Commission (JRC-IET)
License:EUPL 1.1+

The wltp is a python package that calculates the gear-shifts of Light-duty vehicles running the WLTP driving-cycles, according to UNECE‘s GTR draft.


Figure 1: WLTP cycle for class-3b Vehicles


This project is still in alpha stage. Its results are not considered “correct”, and official approval procedures should not rely on them. Some of the known deficiencies are described in these places:

  • In the Changes.
  • Presented in the diagrams of the Tests, Metrics & Reports section.
  • Imprinted in the wltp_db_tests test-case (automatically comparared with a pre-determined set of vehicles from Heinz-db on each build) Currently, mean rpm differ from Heinz-db < 0.5% and gears diff < 5% for a 1800-step class-3 cycle.


The Worldwide harmonised Light duty vehicles Test Procedure, a GRPE informal working group
The United Nations Economic Commission for Europe, which has assumed the steering role on the WLTP.
UNECE Working party on Pollution and Energy - Transport Programme
GS Task-Force
The Gear-shift Task-force of the GRPE. It is the team of automotive experts drafting the gear-shifting strategy for vehicles running the WLTP cycles.
The family of pre-defined driving-cycles corresponding to vehicles with different PMR. Classes 1,2, 3a & 3b are split in 2, 4, 4 and 4 parts respectively.
Unladen mass
UM or Curb weight, the weight of the vehicle in running order minus the mass of the driver.
Test mass
TM, the representative weight of the vehicle used as input for the calculations of the simulation, derived by interpolating between high and low values for the CO2-family of the vehicle.
Reduction of the top-velocity of the original drive trace to be followed, to ensure that the vehicle is not driven in an unduly high proportion of “full throttle”.
The container of data that the gear-shift calculator consumes and produces. It is implemented by wltp.pandel.Pandel as a mergeable stack of JSON-schema abiding trees of strings and numbers, formed with sequences, dictionaries, pandas-instances and URI-references.
The JSON schema is an IETF draft that provides a contract for what JSON-data is required for a given application and how to interact with it. JSON Schema is intended to define validation, documentation, hyperlink navigation, and interaction control of JSON data. You can learn more about it from this excellent guide, and experiment with this on-line validator.
JSON Pointer(RFC 6901) defines a string syntax for identifying a specific value within a JavaScript Object Notation (JSON) document. It aims to serve the same purpose as XPath from the XML world, but it is much simpler.