A proposed investigation into the use of 3D sonar mapping to

characterise the physical state of nuclear containment vessels immersed in a pool of water.

A presentation by Daniel Nye, Lancaster University

Core waste management

• Spent cores are very hot still• Place in ‘Spent Fuel Pool’s to cool down

Some pools have become a little cluttered...(from the Nuclear Decommissioning Authority website)

3D Sonar Mapping

• 3D Sonar Mapping, using Spectral Registration and Plane-Based Registration

An example of Plane-Based Registration (left) and Spectral Registration (right) from Heiko Bülow and Andreas Birk’s paper, ‘Spectral registration of noisy sonar data for underwater 3D mapping’

The Sonar-Boat/Robot

• SLAM – Simultaneous Localisation And Mapping

A demonstration of a simple 2D SLAM robot operating.(from Society of Robots website)

SLAM in Real Time

• Real time SLAM needs a lot of processing power and storage space with normal evidence grid.

• Octree Evidence Grid should be much more efficient

Octrees divide each section into 8, then subdivide those into 8 further. However, these sections can be lumped together if homogenous(from the paper ‘Real-Time SLAM with Octree Evidence Grids for Exploration in Underwater Tunnels’ by Nathaniel Fairfield, George Kantor,and David Wettergreen)

Electronics limitations

• Ionising radiation is bad for semiconductors.

• If the robot stays at the surface it should be able to avoid much of this

Noise• Noise makes it harder to match up relevant

sections when 3D map is made of 2D components.

Sonar scan with noise artifacts (left) and with them removed (right)(from ‘A Post-Processing Method for the Removal of Refraction Artifacts in Multibeam Bathymetry Data’ by Fanlin Yang, Jiabiao Li, Ziyin Wu, Xanglong Jin, Fengyou Chu, AND Zhongzhi Kang)

Testing

• Need to test capabilities of machine and code under controlled conditions, such as the Lancaster University Engineering Department’s wave tank.

LUREG’s Wave Tank(from Lancaster University Engineering Department’s website)

Further Work

• Basically, everything previously mentioned.

• In addition, capability to carry scintillating equipment and software for analysis of the radio-isotopes present (someone else’s PhD project)

Thank you for listening

Any Questions/Suggestionsregarding this

project?