Station Planning/Layout
(updated 31st August 2007)
Keywords: simulating people, simulating crowds, simulating crowd dynamics, modelling stations
Spatial utilisation/Analysis
Why do we need to analysis spatial requirements? The following news report highlights the need to assess space - specifically as queueing systems at airports demand a different use of the space in railways than the original design requirements. Click here for queueing information.
The need for analysis of concourses has been a major requirement of the railways for many years. Tools such as Pedroute work in simple geometries - but can produce inappropriate results when applied to concourse design, optimisation, layout, flow rate analysis and congestion. Myriad solves these problems as the following case study illustrates.
As one of our studies in Saudi Arabia we investigated escalators and escalator safety and studied the largest utilisation of escalators (Al Haram) in Makkah. Drop us a line if you are interested in this research and aspects of our work in crowd simulations.
"It is simply not enough to determine the density of people in a complex space using a simulation - one must present the client with workable solutions in a clear, easily understood format." Dr. G. Keith Still
"I have had a chance this weekend to review your report in detail. My review confirms my initial impression of the report and the other examples on the website: that Myriad is a major advance in spatial planning, in terms of its basic approach, graphic outputs to explain the results to other players, and the speed of response. " Colin Henson, Ove Arup, Australia. 12th October 2002
Focal Route Analysis
By applying a focal route analysis (using Myriad) across the space we can determine those areas which will be used most between the various focal points. This process is "ergodic" in nature and has significant mathematical proof's behind it's validation. The orange areas (diagram below) indicate those areas which encounter the highest number of multi-directional movements during ingress/egress and circulation of passengers in the station concourse area. The concept behind these models is to provide the design/operations team with information about the optimal location of equipment. The diagram below shows part of the process of producing an interaction map indicating the areas where the passengers can experience congestion. To HIGHLIGHT this we have created an artificial environment using an O/D matrix for three major cross flows in this space.
We can see from the diagram above that the location of the operator assisted gate (to the right of the line of POM's) is creating a pinch point on the map (narrowing of the orange area). This clearly indicates that displacing it more to the left of the line of POM's would result in lower congestion, less delays, greater throughput and more natural movement of passengers. Please note - this is an indicative study map produced to highlight the systems outputs. This is NOT a full case study.
Flow rates, queueing times, layout testing and complex spatial analysis are all outputs of the Myriad suite of tools. The Myriad principles can also be applied across a wide range of station environments.
Below we have a Simulex model (left) and the Myriad prediction of the Level of Service in this specific geometry.
Throughput Analysis
The Myriad suite allow us to test for stability in flow down any route through the system. The graph below is indicative of a meta-stable system in which the crowd flow is periodic in nature and suffers from high clustering/interactions (ie: a turbulent journey through the system with a lot of stop-start flows). This is indicative of an unbalanced flow system (multiple cross flows, congestion impairing flow, stop/start movement of passengers in the concourse).
The Myriad suite is highlighting the inefficiencies in the design, namely that there are several "pinch-points" where passengers encounter cross flows and congestion. A more efficient system would sustain a higher peak, have a smoother transition curve and a steep rise and descent (looking like a plateau rather than a mountain ridge). Designing spatial dynamics is a science and this is rapidly gaining momentum with a wide range of multi-disciplinary engineers and consultants around the world.
Circulation maps
Myriad can be used to assess the circulation impact on space utilisation. In the diagram below we have superimposed the escalator flow for both morning and evening traffic. The impact of the geometry on the crowd dynamics is highlighted in the lighter orange areas. Here we can see that there are areas which are under utilised (specifically the left hand corridor). This leads to an increase in pedestrian congestion and subsequent decrease in the passenger flow along that corridor. A subtle change in the local geometry would produce a 50% increase in pedestrian flow (and reduction in congestion) down this corridor. Analysis of flow rates and pedestrian congestion is one of the significant contributions that the Myriad system makes to design and operational planning of complex spaces in places of public assembly.
Interaction mapping
The map below is produced by running bi-direction crowd dynamics models through the Myriad spatial analyser. The red areas have the highest pedestrian conflict and during peak periods these are the areas which will encounter the highest congestion. Mapping the flow congestion AND the pedestrian conflicts give a clearer picture of the spatial dynamics of this complex area. We can see (green section) that the left hand corridor has an area that is low conflict - this corresponds to the area of under utilisation so this space is wasted in the design. The red "hot spot" in the right hand corridor indicates a zone that pedestrians will encounter the maximum conflict (direction changes) and it correspond to an area of highest circulation. An improvement in this area is indicated - namely we need to provide more space for the pedestrians in this critical zone - bottom of escalator. This could be achieved by a small increase (1/2 metre) in the corridor width, a central hand rail/barrier to reduce the conflicts/cross flow or the displacement of the pillars (grey squares in right hand corridor) to focus the pedestrian flow paths and reduce the cross flow conflicts.
Commuter flow
Pedestrian flow is most critical when a one-way, heavy commuter traffic is experienced. To assess the impact of one-way commuter traffic impact against the bi-directional (general) pedestrian traffic we can run uni-directed maps of the same space and compare and contrast the results. The Myriad suite has the facility to assess pedestrian traffic in uni, bi and omni-directional flow patterns - specifically for the conflict and congestion analysis of concourse and complex spaces. Below we see an example of uni-directional flow with a cross corridor interaction (left to right). This highlights a potential improvement in the system, namely the angle of the connecting corridors are creating a pinch-point. If the design were aligned along the flow paths (curved or a less acute angle of approach) a significant improvement in the pedestrian flow would result.
Isometric analysis of space
Interpretation of two dimensional plans requires a certain degree of skill. Myriad has the ability to read isometric plans and produce more easily understood 3D models of the spatial interactions in complex geometries. The diagram below show the utilisation of a multi-level concourse. Here we can see the impact of the ticket hall circulation AND the circulating corridors in a single isometric view of the system.
Crowd Dynamics Ltd produce a range of crowd simulation software and pedestrian analysis tools for computer simulation of places of public assembly.