Myriad
(updated 31st August 2007)
Keywords: simulating people, simulating crowds, simulating crowd dynamics, workshops, simulating people, station simulation. modelling crowds
We have modelled crowds for normal and emergency egress in places of public assembly for over a decade. Crowd Dynamics Ltd produce a range of crowd simulation software and pedestrian analysis tools for computer simulation of places of public assembly.
".........what he's [Keith Still] done is take the best research there is on how people react in fires and try and integrate this so that we can see all of these factors influencing peoples behaviour. And as far as I can tell he seems to have done that quite well.........." Dr Paula Beaver (Ove Arup) on BBC World Services in 1993
"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. October 12th 2002
Screen shots (above) of the Myriad Emergency Evacuation analysis of a building (London) - Spatial Analysis (above right). Travel distance and time analysis (Left) Orange-Red areas exceed the building code requirements for travel distance (when furniture is INCLUDED). Below a series of analysis models and simulations from the Jamarat Bridge Project and below right - images from our multi-building evacuation strategy simulations.
Least Effort - a new way of analysing weaknesses in a system.
Dr. Still has been working on models of least effort in which the system is tested for weaknesses, areas where, if a problem arises, will cause maximum damage with minimum effort. This principle applies to a wide range of human behaviour, social interactions, emergency planning and disaster scenario analysis. Instead of trying various disaster scenarios for an environment (analytically intractable - you may never think of all of the potential threats) you simply turn the problem back to front - what is the least effort required to wreak maximum damage to a system.
Modelling Crowds in Places of Public Assembly
Level of Service A. Flow rate less than 23 people per metre per minute. Virtually unrestricted choice of speed; minimum manoeuvring to pass; crossing & reverse movements are unrestricted.
Level of Service B. Flow rate 23 to 33 people per metre per minute. Normal walking speeds only occasionally restricted; some occasional interference in passing; crossing & reverse movements are possible with occasional conflict.
Level of Service C. Flow rate 33 to 49 people per metre per minute. Walking speeds are partially restricted; passing is restricted but possible with manoeuvring; crossing and reverse movements are restricted and require significant manoeuvring to avoid conflict, flow is reasonably fluid.
Level of Service D. Flow rate 49 to 66 people per metre per minute. Walking speeds are restricted and reduced, passing is rarely possible without conflict; crossing and reverse movements are severely restricted with multiple conflicts; some probability of momentary flow stoppages when critical densities might be intermittently reached.
Level of Service E. Flow rate 66 to 82 people per metre per minute. Walking speeds are restricted and occasionally reduced to shuffling; frequent adjustment of gait is required and passing is impossible without conflict; crossing and reverse movements are severely restricted with unavoidable conflicts; flow achieves maximum capacity under pressure, but with frequent stoppages and interruptions of flow.
Level of Service F. Flow rate variable. Walking speed is reduced to shuffling; passing is impossible, crossing and reverse movements are impossible; physical contact is frequent and unavoidable; flow is sporadic and on the verge of complete breakdown and stoppage.
To allow the user to visualise the above we colour the agents with their appropriate level of service indicator.