Chinese GTOC

[Francesco Topputo]

Meanwhile, the Chinese GTOC has been released.

May I ask our Chinese colleagues to give us details about this year’s problem?

Francesco

---
Dr. Francesco Topputo
Assistant Professor, Politecnico di Milano
Dept. of Aerospace Science and Technology

Ph: +39-02-2399-8351
Fax:+39-02-2399-8334

[Dario Izzo]

Hey,

did not know about this one :) Yes please send here all relevant information

Dario

[杨洪伟]

Hey, I don't participate in this competetion, but I know some information about the Chinese GTOC. 

It is released by State Key Laboratory of Astronautic Dynamics, Xi’an Satellite Control Center (Contact person: Zheng Che, char...@163.com). 

There are two level problems. The participants are free to choose one of them. The higher level problem is about a NEA sample return mission. Different from the previous GTOC problems, the gravity of the Earth, the Sun and the Moon should be all considered. The lower level problem is to optimize the time of escaping our sun system. In this problem, only the sun's gravity should be considered. 

I don't know if there is an English edition of these problems.

--

Hongwei Yang

Tsinghua University

此致

敬礼！

杨洪伟

清华大学航天航空学院动力学与控制实验室

 

>
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[Shen Hong-Xin]

Dear cesco
I will translate it for you, but i only have cellphone now, so please wait me some time.
Ciao

Shen

[Gao,Yang]

A brief introduction to the Chinese GTOC

     In 2005, the first edition of GTOC (The Global Trajectory Optimization Competition) was organized by Dario Izzo of the European Space Agency’s Advanced Concepts Team. At that time, China didn’t have any plan of interplanetary mission and therefore most Chinese researchers in orbital mechanics did not pay much attention on interplanetary trajectory design and optimization. Of course, we didn’t have effective tools for solving the GTOC1 problem. Obviously, GTOC1 introduced the idea of global trajectory optimization to us.
     In 2007, the Chinese first lunar exploration spacecraft, Chang’e-1, was successfully launched. This stimulated us to envisaged interplanetary exploration in China. We also found that trajectory design of lunar and interplanetary missions is much complicated than that for Earth-orbit missions. Based on our understanding of the GTOCs from 2005-2008, the first edition of the Chinese GTOC was initiated in 2009 by Tsinghua University and the 2nd, 3rd, 4th, and 5th editions were each organized in the following years from 2010 to 2013. This year, 2014, the 6th edition is organized by Xi’an satellite control center and the problems are just released. Same as GTOC, following competitions were organized by the winning team of the preceding edition.
     The Chinese GTOC played an important role to introduce global trajectory optimization to a variety of researchers in China, allowing them to start from solving simple problems and then complex ones. Fortunately, I was one of the organizers for the 2nd and 4th editions and I am happy to see that more and more teams with different levels from China could submit solutions to GTOC. As you can see, there are 12 teams registered for GOTC7 and the number of teams that submit correct solutions will exceed those in the past editions. The participants include MS or PhD students, young researchers, and experts in orbit mechanics and trajectory optimization.
     In the 6th Chinese GTOC, a problem for asteroid sample return is released and the spacecraft motion is supposed to be simultaneously influenced by the gravities of Earth, Moon, and Sun. As we know, all problems in the past GTOCs and the Chinese GTOCs from 2009-2013 are based on the patched-conic trajectory model. In fact, to obtain a “best” solution in multi-body gravitational field might be very difficult and advanced design techniques that didn’t appear in the past GTOCs might be utilized.
     I believe that our deeper understanding of global trajectory optimization and our knowledge learned from both GTOC and Chinese GTOC will contribute to the future space exploration. The Chinese GTOC, as a brother of GTOC, will be opened to the world eventually.

Yang Gao
Chinese Academy of Science, Technology and Engineering Center for Space utilization

-----原始邮件-----
发件人: "Dario Izzo" <dario...@gmail.com>
发送时间: 2014年7月17日 星期四
收件人: gtoc_com...@googlegroups.com
抄送:
主题: Re: Chinese GTOC

[Ingo Althoefer]

Dear Yang Gao,

thanks for your very informative description of the situation
in China. It is really nice to have such a large Chinese
delegation in the current GTOC-7 competition.

And it is my hope that your national GTOC competition will
result in a mission that will be flown in the near future.

All the best, Ingo.


Zitat von "Gao,Yang" <ga...@aoe.ac.cn>:

> A brief introduction to the Chinese GTOC
>
>
> In 2005, the first edition of GTOC (The Global Trajectory
> Optimization Competition) was organized by Dario Izzo of the

> European Space Agency?s Advanced Concepts Team. At that time, China
> didn?t have any plan of interplanetary mission and therefore most

> Chinese researchers in orbital mechanics did not pay much attention
> on interplanetary trajectory design and optimization. Of course, we

> didn?t have effective tools for solving the GTOC1 problem.

> Obviously, GTOC1 introduced the idea of global trajectory
> optimization to us.
> In 2007, the Chinese first lunar exploration spacecraft,

> Chang?e-1, was successfully launched. This stimulated us to

> envisaged interplanetary exploration in China. We also found that
> trajectory design of lunar and interplanetary missions is much
> complicated than that for Earth-orbit missions. Based on our
> understanding of the GTOCs from 2005-2008, the first edition of the
> Chinese GTOC was initiated in 2009 by Tsinghua University and the
> 2nd, 3rd, 4th, and 5th editions were each organized in the following
> years from 2010 to 2013. This year, 2014, the 6th edition is

> organized by Xi?an satellite control center and the problems are

> just released. Same as GTOC, following competitions were organized
> by the winning team of the preceding edition.
> The Chinese GTOC played an important role to introduce global
> trajectory optimization to a variety of researchers in China,
> allowing them to start from solving simple problems and then complex
> ones. Fortunately, I was one of the organizers for the 2nd and 4th
> editions and I am happy to see that more and more teams with
> different levels from China could submit solutions to GTOC. As you
> can see, there are 12 teams registered for GOTC7 and the number of
> teams that submit correct solutions will exceed those in the past
> editions. The participants include MS or PhD students, young
> researchers, and experts in orbit mechanics and trajectory
> optimization.
> In the 6th Chinese GTOC, a problem for asteroid sample return
> is released and the spacecraft motion is supposed to be
> simultaneously influenced by the gravities of Earth, Moon, and Sun.
> As we know, all problems in the past GTOCs and the Chinese GTOCs
> from 2009-2013 are based on the patched-conic trajectory model. In

> fact, to obtain a ?best? solution in multi-body gravitational field
> might be very difficult and advanced design techniques that didn?t

> appear in the past GTOCs might be utilized.
> I believe that our deeper understanding of global trajectory
> optimization and our knowledge learned from both GTOC and Chinese
> GTOC will contribute to the future space exploration. The Chinese
> GTOC, as a brother of GTOC, will be opened to the world eventually.
>
>
> Yang Gao
> Chinese Academy of Science, Technology and Engineering Center for
> Space utilization
>
>

> -----????-----
> ???: "Dario Izzo" <dario...@gmail.com>
> ????: 2014?7?17? ???
> ???: gtoc_com...@googlegroups.com
> ??:
> ??: Re: Chinese GTOC

>
>
> Hey,
>
>
> did not know about this one :) Yes please send here all relevant information
>
>
> Dario
>
>
> On Thursday, 17 July 2014 12:41:08 UTC+2, Francesco Topputo
> wrote:Meanwhile, the Chinese GTOC has been released.
>
> May I ask our Chinese colleagues to give us details about this

> year?s problem?

>
> Francesco
>
> ---
> Dr. Francesco Topputo
> Assistant Professor, Politecnico di Milano
> Dept. of Aerospace Science and Technology
>
> Ph: +39-02-2399-8351
> Fax:+39-02-2399-8334
>
>
>
> --
> You received this message because you are subscribed to the Google
> Groups "Global Trajectory Optimization Competition (GTOC)" group.
> To unsubscribe from this group and stop receiving emails from it,
> send an email to gtoc_competiti...@googlegroups.com.
> For more options, visit https://groups.google.com/d/optout.
>
>
>
>
> --
> You received this message because you are subscribed to the Google
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> To unsubscribe from this group and stop receiving emails from it,
> send an email to gtoc_competiti...@googlegroups.com.
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>

----------------------------------------------------------------
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[Francesco Topputo]

Thank you for this historical overview of the Chinese GTOC. Francesco

[Dario Izzo]

Dear Yang Gao,

it is very exciting for me to know about these activities in your country. I am honoured that my initial ideas born within ESA spawned such an interest in China and are delivering a small contribution to your national space programme.

I hope the national competition will soon become an international one .. we could then discuss about possible synergies between GTOCs and maybe organize the events within a common platform ... 

For now, good luck with the current edition and keep us posted!!

Regards,

Dario Izzo

[Gao,Yang]

Dear all,

    Now GTOC7's preliminary ranking has been revealed and your attension might be fouced on the solutions of the GTOC7's problem. Meanwhile, we have figured out a new solution scoring 320/324 to the GTOC6's problem: grand tour of Jupiter's Galilean satellites. Attached are a brief description and data files with the same format in the competition.I guess you might be interested in this new solution in which a new flight mechanism for mapping Galilean satellites is proposed.
    As far as we know,Izzo's team obtained a solution with 316/324 after competition by using evolutionary algorithms,recognized as the current best solution. Therefore, we would like to ask any of your team for verification and confirmation of solution's correctness.We hope it is a closer step to obtaining the maximum score of 324, namely, mapping all faces of the four satellites.

Sincerely,

Yang Gao
Technology and Engineering Center for Space Utilization, Chinese Academy of Sciences

[Petropoulos, Anastassios E (392M)]

Dear Yang,

This looks like a very nice score!  I unfortunately haven't had a chance to verify it yet, but based on your submission at the time of the GTOC6 competition, I expect it will be fine.  I hope to verify the new solution in the coming days.  I am happy to see that there is continued interest in the problem and also an approach to 324/324.

Best regards,

-anastassios

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<gtoc6_flyby_csu.txt><gtoc6_perijove_csu.txt><gtoc6_traj_csu.txt><GTOC6-320.pdf>

[Gao,Yang]

Dear Anastassios,

Thank you for verifying the new solution and congratulations to your team as the winner of GTOC7. The maximum score of 324/324 is "very" possible and  teams in gtoc will reach 324 sooner or later. Meanwhile, we are also curious about  if J = 36 is the maximum point for GTOC7.

Best,

Yang Gao

-----原始邮件-----
发件人: "Petropoulos, Anastassios E (392M)" <anastassios....@jpl.nasa.gov>
发送时间: 2014年8月20日 星期三
收件人: "gtoc_com...@googlegroups.com" <gtoc_com...@googlegroups.com>, "ga...@aoe.ac.cn" <ga...@aoe.ac.cn>
抄送: "Dario Izzo" <dario...@gmail.com>
主题: Re: A new solution scoring 320/324 to the GTOC6's problem

[Ingo Althoefer]

Hello,

for reaching >36 points, "we" will first of all need a large collection
of probe tours (in 6 years) with 13 asteroids or more.

How reasonable is it to get 14-tours and/or 15-tours for single probes?

Cheers, Ingo.


Zitat von "Gao,Yang" <ga...@aoe.ac.cn>:

> Meanwhile, we are also curious about if J = 36 is the maximum point
> for GTOC7.
>
> Best,
>
> Yang Gao
>
>
>

> -----????-----
> ???: "Petropoulos, Anastassios E (392M)"
> <anastassios....@jpl.nasa.gov>
> ????: 2014?8?20? ???
> ???: "gtoc_com...@googlegroups.com"
> <gtoc_com...@googlegroups.com>, "ga...@aoe.ac.cn" <ga...@aoe.ac.cn>
> ??: "Dario Izzo" <dario...@gmail.com>
> ??: Re: A new solution scoring 320/324 to the GTOC6's problem

[Gao,Yang]

Yes, we are waiting for the news of achieving 14-tours or reaching 36+ points. Cheers!

> -----原始邮件-----
> 发件人: "Ingo Althoefer" <ingo.al...@uni-jena.de>

> 发送时间: 2014年8月20日 星期三
> 收件人: gtoc_com...@googlegroups.com

> 抄送: 
> 主题: Re: Re: A new solution scoring 320/324 to the GTOC6's problem