Safety cv software

CV-based Safety Logic

Component owners: Laci, Bálint
Date of assessment: 2016. 05. 09.

Current status

• A live model is maintained

  • The train can move either clockwise or counterclockwise on the track

  • The live model contains the following:

    • Section model: describes sections and switches

    • Train model: current position and speed vector of the trains

• VQL patterns describe unsafe situations

• The live model is built from the information obtained from CV

  • Markers have different colors

  • The markers define the component for the CV. A marker for a train consists of three collinear dots, the color of the middle dot is unique for all trains

  • Special markers: 4 markers in the corners of the desk to identify the system boundary

  • Red, Green and Blue colors are used

  • Helper marker: must be placed to a visible place in order to aid computer vision. It is a small black dot (~1.5 cm in diameter) in the middle of a white square

Issues and TODOs

• The live model is "buggy": it can only represent operation on cyclic tracks due to the clockwise-counter clockwise categorization

• The patterns are not maintained currently, hard to decode their semantics

• Lighting and a better camera is needed (actually, a better camera is already available, but not installed)

• The project and the codebase is not very portable, specific to Bálint’s Mac

  • Needs specific OpenCV build to support GPU (CUDA) acceleration

  • It would be nice to be able to compile the project with cmake

• The base color of the table affects the white-balance in an undesired way. A white desk or some A4 sized blank papers would mitigate this issue

  • A short term advice: fix the helper marker to the desk permanently

Development directions and plans

• The metamodel for the live model should be replaced

  • This is a big task

  • Bálint has started developing this

• According to the new metamodel, the pattern should also be rewritten

  • According to Laci, this wouldn’t take too long to do

• The new lamps should could be mounted to the camera scaffold

  • Alternate configuration: 4 lamps to the 4 different corners

• A long-term plan is to integrate the live model with the distributed logic. The low-level distributed logic implements a fail-stop operation mode, and only a system restart can bring the system back to operation. The purpose of the CV would be to prevent the intervention of the low level logic, and use the latter as a second (backup) safety mechanism

• Bálint plans to continue the work with the project (not all summer)

• Laci: almost the same as Bálint, wants to limit the amount of work on the project