CriticalFinder

[robinlovelace-ate]

• Convert critical issues from inspections into computationally defined variables
• Identify input datasets
• Prioritise cost/benefit ratios
• Find critical issues nationwide
  • Conflict with motor traffic at side roads / priority junctions
  • Conflict with motor traffic at signal controlled junctions and roundabouts
  • Collision alongside or from behind
  • Trip hazard
  • Conflict with kerbside activity (parking, loading, risk of 'dooring' and bus stops)
  • Risk of crossing conflicts
  • Standard of crossing facility
  • Speed of traffic (where cyclists are not separated or pedestrians crossing uncontrolled)
  • Total volume of traffic (where cyclists are not separated or pedestrians cross uncontrolled)
  • Required crossing speed (risk of pedestrians coming into conflict with traffic)
  • Clear walking spaces free of obstructions and furniture, reducing risk of pedestrians walking in the carriageway.
• Publish results

This issue builds on #6 and will add values to the database on infrastructure we hold.

[tom-ate-holcroft]

Four critical issues missing:

• Effective width next to tram line on a straight run
• Crossing angle (between cyclist desire line and tram tracks)
• Cycle surface defects: non cycle friendly ironworks, raised/sunken covers/gullies
• Pedestrian surface defects: non flush tables, misleading tactile information, cracked pacing, slip-risks present from covers, steep slopes

[tom-ate-holcroft]

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Crit Issue #	Critical Issue	Process / Data Required	TH Comment	Ease of Computation (0 hard, 10 very easy)	TH Comment
6	Risk of crossing conflicts	1) Is the traffic flow > 8000vpd? 2) Are there formal crossings present? 3) What is the largest gap between formal crossings? If over 400m then critical.	There is also another critical scenario for roads with <8000vpd which will be very hard to compute ("Are any obvious pedestrian desire lines blocked by parked cars?") For formal crossings definition (see attached Crossings diagram)	8	If we can identify the relevant crossing types and get flow data, this might be fairly straightforward.
11	Clear walking spaces free of obstructions and furniture, reducing risk of pedestrians walking in the carriageway.	1) Is the clear (unobsctructed) footway width <1.0m? 2) Is the clear (unobstructed) footway width <1.5m for over 6m? 3) If yes to either of those, then critical	Absolute minimum acceptable is 1m but only for a length of 6m. Desire minimum is 1.5m. Higher thresholds if footways are crowded.	8
7	Standard of crossing facility	1) Is the traffic flow > 8000vpd? 2) Are there two lanes of traffic to cross? 3) What form of crossing is provided? If uncontrolled then critical. A) Identify signal junctions B) Are there any arms with no green man for pedestrians? If yes then critical	Two separate checks: For links it's 1,2,3; for junctions it's A,B. There is also a 'gaps in traffic' element to this but for ease I would ignore that (with Brian's permission) For uncontrolled crossings definition (see attached Crossings diagram)	7	The link check is more straightforward than the junction check
8	Speed of traffic (where cyclists are not separated or pedestrians crossing uncontrolled)	1) Are cyclists mixed with traffic? AND/OR Do pedestrians cross uncontrolled? 2) If yes, is the 85th percentile speed over 60km/h?		7	Is 85th percentile speed data available? Identifying whether peds cross uncontrolled might be challenging
9	Total volume of traffic (where cyclists are not separated or pedestrians cross uncontrolled)	1) Are cyclists mixed with traffic? AND/OR Do pedestrians cross uncontrolled? 2) If yes, is the total volume of traffic > 1000vpd?		7	Identifying whether peds cross uncontrolled might be challenging
13	Crossing angle (between cyclist desire line and tram tracks)	1) Is there a tramline? 2) Are cyclists expected to cross the tramline at an angle of less than 60 degrees?		7
3	Collision alongside or from behind	1) Are cyclists mixed with traffic in nearside lanes? 2) If yes is the lane width between 3.25m and 3.9m?		6	Depends on accuracy of satellite / other data for lane widths?
5	Conflict with kerbside activity (parking, loading, risk of 'dooring' and bus stops)	1) Is there a cycle facility next to parking/loading? 2) Is there a 0.5m buffer between them?		6	Depends on accuracy of satellite / other data for lane widths?
12	Effective width next to tram line on a straight run	1) Is there a tramline? 2) Is there <2.4m between the kerb and the tram rail and are cyclists expected to cycle in that space? If yes then critical		6
1	Conflict with motor traffic at side roads / priority junctions	1) Identify side roads / priority junctions 2) Are cyclist and ped movements protected? 3) If not, what are the turning counts (motor vehicles per day)	Protected = zebra crossing, continuous footway, modal filter, priority maintained for cyclists (2) is basically "are there red movements if a JAT check were performed?"	5	I imagine (1) is easy, (2) is hard, and (3) depends on what flow data is available.
2	Conflict with motor traffic at signal controlled junctions and roundabouts	1) Identify signal control junctions / roundabouts 2) Are cyclist and ped movements protected/separated in time/space? 3) Turning counts (motor vehicles per day) clashing with any unprotected ped/cycle movements	(2) is basically "are there red movements if a JAT check were performed?"	3	Same comments as crit issue #1 but these junctions are more complex so (2) is hard.
10	Required crossing speed (risk of pedestrians coming into conflict with traffic)	1) Locate signalled pedestrian crossing 2) How long is the crossing? 3) How much time is there for the stage? 4) What speed to peds have to move to get across in time? If faster than 1.2m/s then critical.	This is actually quite a rare critical as most crossings are designed for 1.2m/s or slower.	3	Finding stage times might be hard, everything else can probably be approximated through satelite imagery?
4	Trip hazard	1) Are the level differences of greater than 20mm in the walking environment? 2) Is there any colour contrast to help identify them?		2	Robin mentioned LIDAR but can see this one being challenging!
14	Cycle surface defects: non cycle friendly ironworks, raised/sunken covers/gullies	1) Are there any major defects, such as those listed, in the cycle space?		1
15	Pedestrian surface defects: non flush tables, misleading tactile information, cracked pacing, slip-risks present from covers, steep slopes	1) Are there any major defects, such as those listed, in the pedestrian space?		1

[robinlovelace-ate]

Many thanks @tom-ate-holcroft v. useful!

[dabreegster]

Wow, this is a goldmine! What's the overall goal for us here? To make a guided flow in something ATIP-like to report / record these problems, to try and auto-discover some of them, something else?

[robinlovelace-ate]

Goal: TBC. My thoughts are Long term: to port full functionality of Excel-based tools into a web app architecture. Short term: simply find the critical issues and generating outputs that show where they are could be key.