OSCADY is a software package developed in the UK

United Kingdom

The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

 by the Transport Research Laboratory

Transport Research Laboratory

TRL is a British transport consultancy and research organisation based at Wokingham Berkshire with approximately 500 staff. TRL is owned by the Transport Research Foundation , which is overseen by 80 sector members from the transport industry. TRL also own small UK regional offices situated in...

. The more recent phase-based version of the software is developed by Transport Research Laboratory

Transport Research Laboratory

TRL is a British transport consultancy and research organisation based at Wokingham Berkshire with approximately 500 staff. TRL is owned by the Transport Research Foundation , which is overseen by 80 sector members from the transport industry. TRL also own small UK regional offices situated in...

 in collaboration with UCL

UCL

UCL may refer to refer to:In education:* University College London, a public research university in London, United Kingdom and a constituent college of the University of London* Université catholique de Louvain, Louvain-la-Neuve and Brussels, Belgium...

. OSCADY PRO is the acronym for Optimised Signal Capacity And DelaY: Phase-based Rapid Optimisation.
It is a computer program for optimising phase-based signal timings and calculating capacities, queue lengths and delays (both queueing and geometric) for isolated traffic signal controlled junctions.

(Brief) History

The original stage-based OSCADY was first produced for the personal computer in 1984.



The English language version of the phased-based version of OSCADY (OSCADY PRO) was first released in 2006.



A Japanese language version of OSCADY PRO was released in 2009.

Summary of Capabilities

OSCADY PRO is a tool for traffic signal engineers to help in the design of signal-controlled junctions that use either mixed phase and stage-based traffic signal controllers or pure phase-based ones. Phase timings are optimised by the program to give the best possible junction performance, subject to various criteria, such as safety and user-imposed constraints. As part of the optimisation process, OSCADY PRO will automatically generate and optimise stages and stage sequences.

Since OSCADY PRO only analyses single isolated junctions, it is very simple to use and quick to run. To model networks of all types of junctions (signalised, partially-signalised and unsignalled), an alternative related software package (containing similar technology and techniques) can be employed called TRANSYT

Transyt

TRANSYT is a software package developed in the UK by the Transport Research Laboratory. TRANSYT is the acronym for TRAffic Network StudY Tool.It is used to assess and optimise the performance of networks of road junctions by assigning costs to vehicle stops and delays...

.

How it works

OSCADY PRO is ideally suited to modelling traffic demand that varies over time, such as over a morning or evening peak period. A time-dependant method of predicting queues and delays is used. The method considers the probability od queue lengths as a function of time.

When run, OSCADY PRO finds signal settings that are optimal for the given pattern of traffic according to the following criteria: (which are reported individuallly)

a. critical cycle time

b. maximum practical capacity and

c. minimum delay

Outputs

Average rate of delay

Queue lengths

PRC (Practical Reserve Capacity)

Effective green time

Degree of saturation

Final queue at end of green

Final queue at end of red

Geometric delay

Accident predictions

Phase Delays

Stage sequence

Phase sequence

Optimal phase timings

Current Release

OSCADY PRO 1.3.1 is the latest released version. In additon to its existing features, this version contains a new option to generate a deliberately-simple set of stage sequences as an alternative to its default optimal ones.



International Features:

Drive on the left and drive on the right capability

Alternative phase/stage/signal-group terminology

Japanese version

Further reading

• Summary OSCADY PRO User Guidehttps://www.trlsoftware.co.uk/library/files/general/SUMMARY%20OSCADY%20PRO%20user%20guide.PDF
• An (independent) appraisal of OSCADY PROhttp://www.aensionline.com/jasr/jasr/2009/2117-2125.pdf

External links

• Transport Research Laboratory
• University College London

OSCADY PRO Product Page: http://www.trlsoftware.co.uk/products/OSCADYPRO