Virtual Reality and ALICE By Bjørn S. Nilsen The Ohio State University On behalf of Dennis Sessanna, Ohio Supercomputing Center

Virtual Reality and ALICE

By

Bjørn S. NilsenThe Ohio State University

On behalf of

Dennis Sessanna, Ohio Supercomputing Center

October 26 2004 Presented at MIMOS 2004, Bjorn S. Nilsen The Ohio State Univerity

Over View• Analysis

• Research and Development

• Simulation

• Engineering

• Education


Analysis

• Large Data Sets

• Multi-Dimensional– At least 6 fundamental variables + uncertainties

– Hundreds of derived variables

– Large number of selection criteria

• Large number of different Analysis

– More than 40 particle types + combinations

– More than 6 general analysis techniques

Grid Computing

• No real advantage to use VR based system for seen


Research&

Development

• Emphasis on performance– Mechanical, electrical, thermal, radiation– Suitability to do its specific physics task

• Quality control• Determining production problems• Simpler Engineering and Analysis

A much smaller/limited versionof the experiment

• Not much use for VR system


SimulationPhysics

• Help to determine possible physics goals

• Set and verify design requirements for meet physics goals

• Develop basic analysis procedures

• Measure and correct for inefficiencies– In the detector itself

– In the analysis

• Similar to Analysis – Not a VR candidate

• Has many similarities to VR computing


Physics SimulationsParticle Transport

• Full volumetric representation of detector

• Precision in geometry definitions Fast

• navigation through volumes

• Ray-tracing to & through volumes even for curved rays

• Full volumetric representation of detector

• Precision in geometry definitions

• Fast navigation through volumes

• Ray-tracing to & through volumes



Engineering• Design

– All of the pieces must fit together– The detector needs to be assembled

• Analysis (Simulation)– Structural analysis (static and dynamic)

• Strains and stresses must be within tolerances• Deformation must be within physics

requirements

– Thermal and Electrical• Heat generated must be removed• Temperatures must be within limits set by

detectors…• Electrical system either need to be grounded or

floating


EngineeringDesignAssembly

The ability to view both the whole and parts of the detector, manipulate, and view from many different positions (even through other objects) is invaluable

Parts are being designed at many dozens of places around the world each using their preferred design system (CAD…)

The ability to move pieces around to see how to assemble each piece into the whole

For example, in the ITS we have build at least 2 full size mock ups of this sub-detector just to figure out where to run the cables & cooling lines, and how to install the ITS in the larger ALICE detector

VR will simplify and speed up such work


EngineeringAnalysis (Simulation)

In engineering simulation, one is always needing to relate stresses, temperatures, deformations, to the physical objects them selves and their neighbors.


Education

• Our first use of a full VR system has been for public education about the ALICE detector.– The quality of the data

does not need to be the best

– Minimal software modifications required


VR System Used• VRML files taken from existing CAD files

– OpenScenegraph– 3dsMax / OSGExp

• Good Quality PC with fast disk– Dell Computer, Dual 2.3 GHz Xeon, 1GB Ram

• nVIDIA Quadro 3000 Graphics Card• Nvis Stereo Head Mount Display-1280X1024/eye

• Intersense IS-900 Tracking System– 3x3 m2 tracking area– Wireless wand and head tracker



Other VR system in development/use

• Epidural Simulator

• Tractor Rollover Simulation– Fastrack tracking system

– Virtual-IO force feedback steering wheel

– John Deere – 8400 tractor seat

– Virtual Technologies – 18 sensor gloves

– Biopac monitoring equipment

• Functional Endoscopic Sinus Surgery– Immersion Corporation

• Microscribe - endoscope

• 4DOF force feedback – forceps

– Monitor


Temporal Bone Dissection Simulation

Prototype System• Onyx2 IR2 – 64 MB Texture memory• Virtual Research V8 Binoculars• SensAble PHANToM 1.5• SensAble PHANToM Desktop• Computer Speaker• OpenGL• GhostSDK


Additional• Supply high performance and large cluster

computers to researchers though the state of Ohio– Cray SV1ex, SunFire 6800, Pentium 4

Cluster, Itanium 2 cluster

• Provide facilities for Video conferencing & Advance Learning Environment– BALE multimedia conference room– Access Grid equipped conference rooms

• State wide software license program


Conclusions

• VR is not useful every where, Physics Analysis

• We are already finding it extremely useful and successful in our outreach activities

• VR should find a useful place in Engineering and similar geometry intensive fields

• Our limited experience with VR has us already asking for more.

Documents

Virtual Reality and ALICE By Bjørn S. Nilsen The Ohio State University On behalf of Dennis Sessanna, Ohio Supercomputing Center