MOVA

[SteveA30]

I presume this is the right section for this.
Are MOVA signal systems untouchable, fully automated? Are they unable to be tweaked to respond to changed circumstances on a given road?

[RichardA35]

I presume this is the right section for this.
Are MOVA signal systems untouchable, fully automated? Are they unable to be tweaked to respond to changed circumstances on a given road?

The signal specialists will be able to confirm better, but AIUI MOVA by its very nature optimises for changes in flows (such as flows reversing between morning and evening peaks) without intervention.
However, the specification of the controller will usually have a fallback facility to switch off MOVA and revert to a simpler fixed time plan.
I imagine this could be used in cases of extraordinary special events or closures if the plan has catered for the scenario.

[SteveA30]

OK, thanks for that. Sounds like they could be tweaked for a sudden influx of traffic on to a normally quiet road or adjust themselves, although that doesn't noticeably seem to happen.

[RichardA35]

OK, thanks for that. Sounds like they could be tweaked for a sudden influx of traffic on to a normally quiet road or adjust themselves, although that doesn't noticeably seem to happen.

It would be interesting to hear from the maintenance community whether the signals plans exist that can be implemented during closures.
It was noticeable that during planned overnight closures when the Huntsworth viaduct was being rewaterproofed a couple of years ago, the signals in Bridgwater were clearly running to their normal plans which naturally led to long queues through the town.

[SteveA30]

That's what I find at the various diversion locations I lurk in. I mentioned this to Glos CC re A38 lights and after the usual being passed from dept to dept, received the reply that MOVA is pre-programmed and can't be altered.
The only one of the 5 sets of signals that don't cause summer Saturday queues, are those at J16 Almondsbury, indicating that they are at just the right setting or, adjust themselves according to circumstances. The 4 on the A38 cause queues of from 1/4 mile to 2 miles. I suppose if the traffic sailed through those, they would overwhelm J16 so, a lose/lose situation.

[RichardA35]

That's what I find at the various diversion locations I lurk in. I mentioned this to Glos CC re A38 lights and after the usual being passed from dept to dept, received the reply that MOVA is pre-programmed and can't be altered.
The only one of the 5 sets of signals that don't cause summer Saturday queues, are those at J16 Almondsbury, indicating that they are at just the right setting or, adjust themselves according to circumstances. The 4 on the A38 cause queues of from 1/4 mile to 2 miles. I suppose if the traffic sailed through those, they would overwhelm J16 so, a lose/lose situation.

It may be worth looking at any photos or Google Earth to see whether the installations are actually MOVA equipped. My experience would tell me that multi arm junctions or interchanges would possibly be MOVA equipped but not simple crossings or junctions. Local authorities tend to not go the expense of MOVA unlike HE where everything is MOVA by default.
The telltale signs are that the initial approach loops are diamond shaped

[SteveA30]

Thanks, I'll look through my many photos to see if there are any diamonds on the A38.

[GrahameCase]

MOVA was recently installed on the A8/M9/M8/A89 Newbridge Roundabout - they had to switch them off and let the police manually control traffic during the Royal Highland Show as they weren't able to cope with the increased traffic flow

[ianwallis]

OK, thanks for that. Sounds like they could be tweaked for a sudden influx of traffic on to a normally quiet road or adjust themselves, although that doesn't noticeably seem to happen.

It would be interesting to hear from the maintenance community whether the signals plans exist that can be implemented during closures.

In simple terms, several MOVA datasets can be held within the MOVA unit and can be implemented by time of day change points if a single set of parameters isn't suitable at all times. One of the main principals behind MOVA is that it can make "intelligent" decisions so you allow the possibility to run longer greens than usual on the basis that it will only do this if necessary and appropriate (intelligent decision making). Hence why MOVA is considered capable of adapting to tidal flows or sudden influx of traffic as Richard suggests - but only if the engineer has set up the dataset in that way.

In terms of changes to datasets for closures or big events it depends on your highway authority and how bothered they are. Certainly here in Derby we will install revised datasets for long term road closures (more than a day usually) and it's quite an easy thing to do because the original dataset exists so it can be used as the basis of the revised dataset. Of course if you don't do them yourself and rely on consultants / contractors then the costs may influence what happens.

[SteveA30]

South Glos said they can't be adjusted. I guess that either they are not interested or, as you mention, outside contractors are involved.