What do you do if you want to optimize traffic signals in transportation planning?

Data collection is the basis of all types of traffic analysis. A traffic and transport engineer can not do any decision with out having data about it. For both current case analysis and future improvement analysis the data is crucial where it can give you the performance of the current services and infrastructure , where decision makers can use it the result for necessary improvements.

One key element of specifying traffic signal requirements, is to use an experienced traffic signal design engineer to sense check the operational assumptions which have been made during the modelling process. I have seen many recommendations for signalised sites over the years where inexperienced practitioners have had unrealistic expectations for signals overcoming spatial constraints, or not accounting for issues such as downstream congestion causing exit blocking for sites.

It is possible to analyze the collected data macroscopically and microscopically based on the details and quality of the data. The macroscopic analysis can give us the overall performance of the systems and networks, where as the results of the macroscopic analysis will show us, how the part of the systems works, including the traffic ??s and how affect each and every vehicle types to the whole system and themselves. Based on the results of the performance inductors, a decision can be made how to improve the system for short and long interval of time.

Based on the results of the performance indicators, like level of service, delays, one can decide the measures to be taken. It should be changed to roundabout, signalized intersections and fixed, actuated, partial ?? and so on. Engineers will choose which types of signal timing will improve the system for now case and the future case as well.

That's correct, adaptive signal is effective but not affordable by all concerned bodies who are within the transport adminstrations.

Adaptive or Vehicle Activated (VA) signals should be a de-facto method of operation for traffic signals. Even locations which suffer from high-levels of congestion (where a quasi-fixed time operation will inevitably operate during peak periods) will benefit from VA operation off-peak, overnight, weekends etc. This becomes particularly important during quiet periods where signalised pedestrian facilities exist at sites, because it minimises waiting periods for pedestrians to cross.

I agreed with your suggestions.Public engagement is necessary especially during data collection stage where they can contribute with their day to day challenges and the engineer will use this input in addition other datas and will help to decide the right solution for the problems.

The operation of traffic signal installations should be confirmed and optimised as part of the commissioning process. It is also good practice to come back to the site of a short period of time, say 3-months, to Validate the ongoing operation once drivers have got used to the facilities. Again, their operation can be optimised at this point if any issues or improvements are identified. This is normally conducted over a number of sessions, such as AM peak, inter-peak, PM peak, maybe weekend if it has a particular relevance to the site. Traffic flows change over time, so the site should then be periodically (every few years) assessed to see how it is performing over time, and re-validated and optimised as required.

There should be visible signs of enforcement present at the junctions. Enforcement may be in form of traffic police personnel for short term and automated enforcement solution like camera detection for long term basis. This acts as deterrent for vehicle drivers to follow traffic rules. Another major aspect of Traffic Juction is pedstrian users . They should be given priority for right of way. This can be thru walkover bridges or under pass which are more capital intensive but most safe. Low cost solution would be dedicated Pedstrian phase & demand buttons ,but they distrupt free flow of traffic impacting the whole idea of signalisation.

Many optimization studies are only concerned with the effects on drivers and ignore pedestrians and cyclists. Examinations of signal timings as part of optimization studies should consider possible improvements for other road users, when appropriate. In urban, high pedestrian flow areas, consideration should be taken to understand any negative impacts on pedestrian levels of service and crowding and safety, that changing signal timings may have.