L2.01 Can I Load a LinSig V1 file?
Yes. LinSig V2 will load in all the data included in the LinSig v1 file. However, since LinSig V2 uses a large amount of extra information, there will be some LinSig v2 specific data that will not be available in the LinSig V1 file and this will need to be added manually after loading.
At the very least, the following will need to be added:
Exit Arms and Link Connectors to the Exit Arms.
Add Zones that represent origins or destinations for traffic entering or leaving the network.
Add a Traffic Flows matrix defining the flows from Origin Zone to Destination Zone. The Link flows imported from the LinSig V1 file can currently be found in the Link Grid Data View (on the Junction menu).
L2.02 One of my views keeps disappearing behind a larger View.
All the Views in LinSig V2 have an Always On Top feature that ensures that they remain visible on top of other Views. You can set any View to be Always On Top by clicking the drawing pin button in the top right-hand corner of the view.
This is especially useful for having a smaller view on top of a larger view, for example to have the Intergreen View on top of the Junction Layout View.
But beware of setting a large view to be always on top or all your other views may be hidden behind it!
L2.03 Why are there no routes? I’ve added Links and Connectors.
The Route List View will display all the routes through your model. LinSig automatically keeps this list up to date. If there are no routes in the list, this is most likely because the appropriate Zones have not been created.
In LinSig, a Route is defined as starting at an Origin Zone and ending at a Destination Zone. In order to add Zones, select Junction … Add Zone in the Junction Layout View, position the Zone as required and then specify which Arm is the entry Arm at that Zone and which Arm is the exit Arm at that Zone.
L2.04 How do I model multiple stage streams in my controller?
LinSig now has the facility to model multiple Stage Streams. However, as many straightforward junctions only require a Single Stage Stream, LinSig defaults to Single Stage Stream mode. The mode can be switched in the controller settings at File…Settings For This File…Allow Multiple Stage Streams.
When you are in Multiple Stage Stream mode, the Stage View now displays a row of stages for each Stage Stream. Phases can be added to or removed from a Stage Stream by double-clicking on the phase in the left-hand box for that stream.
L2.05 Why is the Link Results View not showing any results?
It is most likely that there is an error in the model that is preventing LinSig from being able to calculate results.
The Error View lists any errors and warnings in the LinSig model along with their location and severity. Double-click on an item in the Error View and LinSig will highlight the cause of the problem.
L2.06 Why are there no arrows on my newly created links?
LinSig V2 requires that you add Link Connectors to define the movements on your links.
Link Connectors define which traffic movements are allowed between Links on different Arms. When modelling a single junction, Link Connectors simply define which Exit Arms traffic from each Link may travel to.
Link Connectors are added in the Junction Layout View by dragging with the mouse from one Link to another Link.
L2.07 How do you explain different results between LinSig V1 and LinSig V2?
For simple Links LinSig V2 should give similar capacity results as LinSig V1. The Right Turn Model has been improved to model a number of effects the Webster & Cobbe model used in V1 couldn’t handle so this will lead to improved accuracy in some cases.
Delays and queuing are modelled in a completely different way in LinSig V2 than LinSig V1. Delays and queuing in V1 were again based around Webster and Cobbe and did not attempt to model variations of queues within cycles in any way and included assumptions on the randomness of arriving traffic. LinSig V2 explicitly models queue variation within a cycle and includes different assumptions of the randomness of arrivals. This is designed to tie in better with changes in assumptions in other software such as TRANSYT, not necessarily because any particular assumption is universally better or worse, but to achieve greater consistency between different models. I would therefore expect some differences (which may be quite large at short queue lengths) in queuing between the models, but generally LinSig V2 is modelling things in a more sophisticated manner and should therefore be a ‘better’ result. As with all queuing estimates though remember to compare like with like as there are many different definitions of ‘queue’.
L2.08 What’s happened to the ‘Short Lane Only Links’ option from LinSig V1?
The use of Short Lane only Links in LinSig V1 was provided only to allow some very rare specialist cases to be modelled. As some users mistakenly used Short Lane only Links inappropriately it was decided to remove the Short Lane only Links option to prevent confusion in LinSig V2. Whilst the option was available in LinSig V1 we found only a handful of cases where short lane only links were used correctly. If you feel you have a valid use for Short Lane only Links please contact us and we will consider reinstating this option if appropriate. With LinSig V2.4 and above you may find the new model for opposed short right turn lanes may be more appropriate than this option. Please contact us ((01522) 751010) if you require any further advice on this issue.
L2.09 I’ve created two scenarios, one for AM Peak and one for PM Peak. If I optimise the AM Peak Scenario and then switch to the PM Peak scenario and optimise that, when I go back to the AM Peak scenario the timings and results have changed. What am I doing wrong?
In LinSig 2.3 and below, the Signal Plan stores both the Stage Sequence AND the timings for that stage sequence. So, if you need to store different sets of timings then you’ll need a separate signal plan for each set of timings. (You can use the “Copy Signal Plan” function to help create multiple Signal Plans.) In this example you’ll need an AM Peak Signal Plan and a PM Peak Signal Plan. Then make sure that each scenario is using the appropriate Signal Plan, and the timings for each Scenario will be independent. LinSig V2.4 introduces a new system of Scenarios and Staging Plans which overcomes this issue.
L2.10 When I select a different Flow Group in the Traffic Flows View or a different Staging Plan in the Staging Plans View the LinSig results don’t change.
Some subtle changes have been made to the user-interface in how you use Flow Groups, Staging Plans and Scenarios.
In the previous version of LinSig (version 2.3), there were Flow Groups and Signal Plans. Whichever Flow Group was currently selected in the Traffic Flows View (or selected in the drop down list on the toolbar) was the Flow Group that LinSig used for calculating and displaying results. Similarly, whichever Signal Plan was currently selected in the Signal Plans View (or selected in the drop down list on the toolbar) was the Signal Plan that LinSig used for calculating and displaying results.
You could also optionally create a Scenario, defined by specifying a Flow Group and a Signal Plan. Then, when you selected the Scenario, LinSig would ensure that its Flow Group and Signal Plan were also currently selected – this simply acted as a shortcut for manually selecting the Flow Group and the Signal Plan.
In the latest version of LinSig (version 2.4) this has changed as follows. Firstly, Scenarios are now mandatory. You still define a Scenario by specifying a Flow Group and a Staging Plan (no longer called Signal Plans). The important thing to note is that LinSig now calculates and displays results for the currently selected Scenario. This means that it doesn’t matter which Flow Group you’ve selected to look at in the Traffic Flows View or which Staging Plan you’ve selected to look at in the Staging Plan View, LinSig will always calculate and display results using the Flow Group and Staging Plan that you’ve specified in the currently selected Scenario.
You can think of the Traffic Flows View as showing a menu of available Flow Groups, and the Staging Plans View as showing a menu of available Staging Plans, and from these menus you choose the appropriate ones for each Scenario that you create.
So in a typical example, you may have two Flow Groups, namely “AM Peak” and “PM Peak”. You may also have two Staging Plans, say, “Sequence with Left Filter” and “Sequence Without Left Filter”. You could then define four Scenarios as follows:
Scenario 1: AM Peak, “Sequence with Left Filter”
Scenario 2: PM Peak, “Sequence with Left Filter”
Scenario 3: AM Peak, “Sequence without Left Filter”
Scenario 4: PM Peak, “Sequence without Left Filter”
This has the immediate advantages over the way LinSig used to work in version 2.3. It is easier to manage your Scenarios – no longer any need to have duplicate copies of Signal Plans for each Scenario. Furthermore, the Scenarios View allows you to see summary results for all your Scenarios at once and gives you the ability to batch optimise some or all of your Scenarios at once.
L2.11 I have a file created in version 2.3 that didn’t make use of Scenarios. How will this be loaded into version 2.4?
LinSig 2.4 knows that a LinSig 2.3 file may or may not contain Scenarios and does its best to convert them when loading. No information is discarded during this process, although it is possible that LinSig may create extra Scenarios for combinations of Staging Plans and Flow Groups that were not originally intended (these Scenarios can of course be manually deleted after the file has loaded). If the LinSig 2.3 file already has Scenarios defined, they are loaded straight in. New Scenarios are created for any Signal Plans that aren’t already used in a Scenario, retaining the timings. If there’s only one Flow Group, LinSig will automatically assign that Flow Group to each new Scenario, however if there is more than one Flow Group then LinSig will leave it up to the user to assign the Flow Group in those Scenarios.