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Re: [simspark-devel] [Rc-ss3d-tc] Immediate help is needed for preparation!
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From: Klaus D. <kla...@hs...> - 2012-03-20 19:07:27
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Hi Hedayat, sorry, short in time. I think that changing the foot height does not dramatically change most of the behaviors except kick. All motors and joints remain the same. If it helps to allow high kicking I am still in favor of reducing foot height instead of increasing ball size, which looks unnatural quickly, when the ball is up to the knee. Greetings Klaus Am 20.03.2012 11:24, schrieb Hedayat Vatankhah: > Hi Klaus, Patrick and others! > > Thanks a lot for your efforts. We can increase the ball size. However, > about the foot height, I'd personally prefer to have our robot > dimensions follow the real Nao. If I have understood correctly, > decreasing the foot height should have the same effect as increasing the > ball size. So, isn't it enough to slightly increase the ball size > (without having an unusually big ball)? And it would be great if we can > send the initial suggestion to sserver-three-d mailing list today. What > do you suggest? > > > Regards, > > Hedayat > > > /*Klaus Dorer <kla...@hs...>*/ wrote on Fri, 09 Mar 2012 > 07:02:14 +0100: >> Hi Patrick, >> >> thanks a lot for your work! >> >> Stefan has also evaluated some settings. Below his findings. >> His conclusions are quite close to yours. Increasing ball mass seems >> odd, at least as long as friction is kept the same. He also suggests >> only marginal increase in ball size. >> The only difference is with respect to foot height. He suggests to >> shrink the foot. >> In my oppinion this would allow more flexibility, i.e. the initial >> situation does not require too much precision or put in other words, >> kicking high from various ball distances and situations can be achieved. >> >> >> Greetings >> Klaus >> >> Stefan: >> >> The magmaOffenburg agent is capable of two different forward kicks, >> one that is wider, like a normal kick, and one that is faster, called >> FastKick, that is more like rising the leg while standing. It's hard >> to describe, but the FastKick should basically lift the ball up, but >> less wide. >> >> Results: >> 1) foot height: 1.5cm, ball radius: 4.2cm (old) >> - 13g (old/2): >> - Kick: ball hardly leaves the ground >> - FastKick: shoulder to head height (relatively reliable) >> - 26g (old): >> - Kick: ball hardly leaves the ground >> - FastKick: head height (reliable) >> - 39g (old+13): >> - Kick: ball hardly leaves the ground >> - FastKick: head height (reliable) >> 2) foot height: 1.5cm, ball radius: 5.2cm >> - 13g (old/2): >> - Kick: knee to hip height - it is easily able to push the >> foot fast enough below the ball, but then the ball doesn't get much >> momentum and simply drops down again (like a trick kicker, balancing >> the ball) >> - FastKick: hip height - it isn't realy able to get below the >> ball. The FastKick accelerates the leg directly at the ball and the >> ball seems to take the acceleration easier when it is leighter. >> - 26g (old): >> - Kick: same behavior as with 13g >> - FastKick: head height (reliable) >> - 39g (old*2): >> - Kick: ball hardly leaves the ground >> - FastKick: head height (reliable) >> >> In general with a heighter foot, like e.g. 2cm, our kicks aren't realy >> able to get below the ball. If I rise the size of the ball radius by >> another 1cm (to 6.2cm), the ball slowly is as high as the knee and it >> happens somethimes that it touches the ball with its knee. At that >> size our kicks are also not realy capable any more to kick the ball >> appropriately. With some tweaks it may well be possible to kick it >> better, but at that size it also looks strange... >> >> Overall I realized that the weight of the ball has less impact on if >> it's high kickable. On the other hand, the size of the ball has less >> impact on the kickable distance. >> The following observations were made: >> - if the ball weight is reduced, the friction has a higher impact on >> the ball's speed, reducing possible kick distances drastically. If it >> is enlarged, the friction has less impact on the ball's speed, but it >> quickly results in an odd ball movement. It is rolling very long and >> stopping too slow. >> - If the ball gets too big, it is hard to get the foot of the agent >> stretched below the ball in such a way that it kicks proper off the >> ground. But as logical consequence, it has a bit less friction and >> gets farer. >> - If the ball is bigger, it is easier to kick in different directions >> >> After several hours ot testing I think that both values for the ball >> are well balanced. According to wikipedia, a soccer ball has a radius >> of around 10cm. We use 4.2cm, wich is around half the size, but I >> think we have to consider more the ratio of foot height to ball >> radius. We have a robot that is 1/3 of the size of a human, so it >> should get around 1/3 of the foot height. If I take a rough estimation >> of the height of the box of my personal foot, I would say it's on >> average around 3cm in the front. With this, to change the foot height >> to a value between 1 to 1.5 cm sounds reasonable to me and the results >> also show that with a thinner foot around 1.5cm, kicking high is not >> the biggest problem any more, even without changing the ball parameter >> too much. >> >> The kick distance is more problematic. Wikipedia says that the >> international ball weight is above 400g. We currently have 26g... As I >> sad, rising the ball's weight is not really the best option as long >> the field friction is kept the same. We may be able to adjust the >> values slightly, e.g. a ball radius around 5cm and a weight around >> 30g, to make a step towards more distance in kicking, but I would need >> to make some other experiments to fine tune my suggestion for real >> values. In the above experiments with 5.2cm radius and 39g weight, the >> ball movement was already quite odd and the gain in distance was from >> initially 4.5m to around 9m - not even half the field. >> >> In general the results are just my opinion and other teams may well be >> able to kick higher and/or wider with the same parameters. My >> suggestion with respect to well balanced values for foot height, ball >> radius and weight are: >> - foot height: 1 to 1.5cm >> - ball radius: 4.5 to 5cm >> - ball weight: the same >> >> The suggestion to the field size is hard. I would suggest to adapt to >> a field size of 1/3 of the internaltional commen field size for >> humans. This would be around 1.75 times the current size. >> >> The extension of the HipYawPitch to a range of -120 to 60 could be an >> option, since it fits better to the human leg range. Although in my >> opinion the above range is a bit too much and a change in the >> HipYawPitch itself is not enough. If we allow for a wider range here, >> we also need to adjust the range of the other two hip joints to allow >> the intended leg-freedom for kicking. But, over the last months I also >> came to the conclusion that the Nao is allready quite flexible and >> this kind of leg-feedom doesn't bring too much benefit. We have kicks >> going to the right, left, front and back if the agent is standing >> still. I could also come up with kicks in e.g. 10 degrees steps, but >> as long as I have to stand still, there is no real benefit in more >> kick directions. And if I can shoot while walking, I should walk >> better ;) Humans also often do a final step before kicking. >> >> So, I hope I could help you with my suggestions and thoughts to >> clarify the values for the upcomming events. If you need any further >> help or have some questions about my tests/thoughts, you are very >> welcome to ask. >> >> >> Am 08.03.2012 05:24, schrieb Patrick MacAlpine: >>> Hi all, >>> >>> Based on the proposed changes to the 3D simulation competition, >>> particularly that of kicking, I've optimized one of our kicks for >>> distance through machine learning in order to create some benchmarks >>> for how changes might affect things. The following are numbers I've >>> collected on optimizing a kick for which the ball is beamed to a set >>> place in front of the agent. While these numbers show what is >>> possible in the server, we have made no attempt yet to integrate the >>> kick into our agent such that it is able to walk up to and position >>> behind the ball before kicking it. These numbers should be considered >>> a lower bound for what is possible in the server, but with the caveat >>> that it may be hard to achieve their full potential without very good >>> positioning. >>> >>> Current server: Distance = 12m with a height of 1.4m+ (2.5X height of >>> a Nao) >>> Ball at half mass (.013): Distance = 8m with similar height above >>> Ball at double mass (.052): Distance = 17m+ with similar height above >>> Ball at +50% radius (.063): Distance = 16.5m with height greater than >>> Nao although lower for longer kicks >>> Foot Z half value (def $FootSizeZ 0.015): Distance = 12.5m with a >>> height of 1.8m (3X height of a Nao) >>> >>> Based on the numbers above it seems that the goals of kicking above >>> the height of a Nao (which was not something that the kicks learned >>> were optimized for) as well as a distance 2/3 the length of half field >>> (which is 10.5m if the field is increased by 50%) are already >>> attainable. Decreasing the mass of the ball will only decrease the >>> length of kicks whereas increasing the mass of the ball would >>> increase kick length. This increase in distance with more mass occurs >>> because once the ball hits the ground it rolls farther due to it >>> having more momentum with greater mass. I'm not really in favor of >>> increasing the size of the ball as it starts to look a little silly >>> with its larger size relative to the Nao and also a larger size will >>> make it harder to get the ball by a goalie and score goals. The >>> larger ball rolls farther after hitting the ground when compared to >>> the regular size ball, which is the reason for longer distance kicks, >>> and makes me think that increasing the ball's radius also increases >>> its mass. Decreasing the height of the foot seems to add a little >>> distance as well as height to kicks but not by a considerable amount. >>> If there are other changes to server parameters or combinations of >>> server parameters that you wish to see benchmarked let me know and I >>> will try to run them (time permitting). >>> >>> I'm OK with changes to the field size if it makes things better match >>> the ratio of the real world, however if we do this I think we should >>> also match in the number of players (11). This way the amount of open >>> space and area which individual players need to cover is also similar >>> to the real world. >>> >>> I like the idea of adding heterogeneous players and think this would >>> add a really interesting component to this year's competition. We're >>> currently exploring how modifying the dimensions of the robot model >>> affects aspects of play, such as an agent's walking speed and >>> stability, so as to find a range of parameter values that can be >>> changed to create heterogeneous robot models without unbalancing >>> gameplay. >>> >>> Regards, >>> Patrick MacAlpine (UT Austin Villa) >>> >>> >>> >>> On Fri, Mar 2, 2012 at 1:57 PM, Hedayat >>> Vatankhah<hed...@gm...> wrote: >>>> Dear all, >>>> >>>> As you can find in the attached document, TC has decided for a few >>>> adjustments/enhancements in the simulator for 2012 competitions. It is >>>> really nice if we can get these changes ready ASAP, so that we can >>>> use at >>>> least some of these changes in upcoming open competitions (IranOpen and >>>> DutchOpen). Sorry for being a little late :(. >>>> >>>> Anyway, according to the document, most of the changes are some >>>> parameter >>>> adjustments. We need your help to find some suitable values to >>>> suggest and >>>> request feedback from the teams. The primary parameters to adjust are: >>>> - ball size >>>> - ball weight >>>> - foot height >>>> - possibly foot shape if that is possible >>>> >>>> And the secondary parameters to adjust is then: >>>> - field size >>>> >>>> >>>> It's great if we can have some values in less than a week and then >>>> discuss >>>> those values in the list with all teams. Any help is highly >>>> appreciated! :) >>>> >>>> Thanks >>>> >>>> Hedayat >>>> >>>> >>>> >>>> ------------------------------------------------------------------------------ >>>> >>>> Virtualization& Cloud Management Using Capacity Planning >>>> Cloud computing makes use of virtualization - but cloud computing >>>> also focuses on allowing computing to be delivered as a service. >>>> http://www.accelacomm.com/jaw/sfnl/114/51521223/ >>>> _______________________________________________ >>>> Simspark Generic Physical MAS Simulator >>>> simspark-devel mailing list >>>> sim...@li... >>>> https://lists.sourceforge.net/lists/listinfo/simspark-devel >>>> >>> _______________________________________________ >>> rc-ss3d-tc mailing list >>> rc-...@li... >>> http://lists.robocup.org/listinfo.cgi/rc-ss3d-tc-robocup.org >> _______________________________________________ >> rc-ss3d-tc mailing list >> rc-...@li... >> http://lists.robocup.org/listinfo.cgi/rc-ss3d-tc-robocup.org |
