A photorealistic render generated by Blander-based Space Imaging Simulator for Proximity Operations (SISPO)
which is used to model Comet Interceptor instruments and characterize their performance.

​

UT Tartu Observatory develops Optical Periscopic Imager for Comets (OPIC) onboard the European Space Agency’s mission Comet Interceptor. Aalto University School of Electrical Engineering contributes to the software development of OPIC and Entire Visible Sky (EnVisS) instruments. EnVisS development is led by UCL Mullard Space Science Laboratory and its data handling unit (DHU) is developed by the Institute of Astrophysics of Andalusia. Flight software is developed in collaboration with an industrial partner Huld. The mission consists of three spacecraft – the main spacecraft A and two ‘subspacecraft’ B1 and B2 – which will perform the first-ever flyby of a dynamically-new Öpik–Oort cloud comet whose characteristics will largely remain unknown before the launch. The instruments are placed on spin-stabilized B2 which will perform a close and risky flyby with a useful imaging time of a few minutes. Before and during the flyby, EnVisS and OPIC are required to operate autonomously. Since B2 might be damaged due to dust impacts, on-board software must be able to prioritize, compress, packetize and transmit images in a stream-like mode. The following research (e.g., MSc thesis) topics are available.

1. Implementation of and instrument performance characterization with Comet Interceptor Engineering Dust Coma Model

This thesis topic focuses on the implementation of Comet Interceptor Engineering Dust Coma Model (EDCM) in SISPO. The purpose of the EDCM is to make predictions of which dust the spacecraft will encounter visually and mechanically during the active phase of the mission. The simulator already implements a similar model but a new mission-wide model is required to characterize the instrument performance. Signal-to-Noise Ratio (SNR) has to be estimated in order to characterize the capabilities of imaging the dust particles. Impact of dust particles on the B2 orientation has to be modelled in order to characterize the off-pointing of instruments. The goal of the thesis is to implement the EDCM in SISPO and simulate the performance of OPIC and EnVisS with respect to dust imaging capabilities and dust impacts. EDCM and its documentation is available upon request.

2. Implementation and optimization of Comet Interceptor Engineering Gas Coma Model

This thesis topic focuses on the implementation of Comet Interceptor Engineering Gas Coma Model (EGCM) in SISPO. The EGCM is based on (Haser, 1957) with several simplifying assumptions and represents a subset of EDCM cases (see above). The simulator already implements a similar model but a new mission-wide model is required to characterize the imaging capabilities of the gas coma. In conjunction with the EDCM, the implementation has to be optimized for the use on personal computers and if needed with high-performance computing. The goal of the thesis is to implement EGCM in SISPO, integrate with EDCM and optimize it for personal and HPC use cases. EGCM and its documentation is available upon request.

3. Prototyping of on-board image acquisition and processing algorithms on field-programmable gate array

This thesis topic focuses on early prototyping of FPGA algorithms for imaging, prioritization, compression and/or packetization. OPIC and EnVisS are equipped with 3D Plus 3DCM734-1 camera heads which have integrated ProASIC3 FPGAs. The algorithms are developed and tested using renders generated with SISPO. The goal of the thesis is to select, implement and characterize the performance of FPGA-based image acquisition and processing algorithms in order to understand which algorithms are suitable for flight software implementation.

4. Prototyping of on-board image compression for Comet Interceptor OPIC and EnVisS instruments

This research topic focuses on implementing and characterizing on-board compression algorithms. Several existing compression implementations are considered. CCSDS includes a range of space image compression methods. CCSDS 122 employs discrete wavelet transform for decorrelation of monochrome images and bit-plane encoder which encodes the decorrelated data. JPEG 2000 is the consumer market equivalent of CCSDS 122. CCSDS 123 provides lossless or near-lossless compression of hyperspectral data. Basic run length encoding methods might provide a simplified and sufficient solution. The goal of the thesis is to characterize existing solutions on PC, microcontroller and, optionally, FPGA platforms, and advise the instrument teams on the most suitable image compression solution. The characteristics include the implementation complexity, required hardware resources and execution time.

5. Development of on-board image prioritization for Comet Interceptor OPIC and EnVisS instruments

This research topic focuses on developing and characterizing on-board image prioritization algorithms. SISPO is used to generate photorealistic renders, accounting for a range of variables: flyby velocity and geometry, comet size, cometary activity, etc. Prioritization algorithms are developed and tested using the synthetic imagery in conjunction with data reduction approaches, such prioritizing a downsampled image followed by high-resolution details of the same image. Physical flyby tests are planned to be performed at Asteroid Engineering Laboratory on the Luleå University of Technology’s Kiruna campus. The goal of the thesis is to prototype and characterize on-board image prioritization algorithms which will be implemented as flight software.

​

Please contact Andris Slavinskis for additional information: UT Tartu Observatory, Estonia <andris.slavinskis@ut.ee> & Aalto University, Finland <andris.slavinskis@aalto.fi>. Students and researchers from other institutions are welcome. Remote work and exchange are possible. Both UT Tartu Observatory and Aalto University are hiring.