Society of Robots - Robot Forum

Software => Software => Topic started by: benji on March 25, 2008, 12:59:13 PM

Title: choosing goal suggestions (mapping)
Post by: benji on March 25, 2008, 12:59:13 PM
hello folks, finally im done implementing the A-star algorithm over Matlab and i made it handles orientations and smooth the way to the goal.
the thing is the way im choosing the goal takes big time to be done,
i am checking all available unmapped areas to go to
i run the A* at all of those
i choose the one with the smallest cost as a goal and i move there
this way is the best but it take a heck of a time thats because the A* takes about 5 seconds to run and if i have
lets say 50 available points to go then that would be 250 seconds thats about 5 minutes...... :(

so i want to choose a goal to go to in an intelligent way but not that time consuming,,,,
any seggestions would be welcome
Title: Re: choosing goal suggestions (mapping)
Post by: Ro-Bot-X on March 25, 2008, 02:59:19 PM
I am not done with my robot, I mean I still have a lot of hardware stuff to deal with, then figure out how the low level functions will work (and mapping is one of those functions) until I will be in your shoes.

But here are my thoughts:
- have the robot interact with it's environment
- have the robot interact with people
- have the robot to have moods, like happy, bored, hungry, active, curious...

The moods will trigger some related actions, for instance if it's hungry it will find the charging station to feed, if it's fed it becames active and looks around for people to play with, if it doesn't find people it becames bored and just sits there for a while, if it gets curious it explores the environment, if it finds some small objects that it can grab it takes them away and maybe hides them in a secret place...

This is a pet robot. You may want to play fetch with the robot, or have it take some object to a specific place in the room or to some other person. There may be a guardian robot, or a buttler robot, or a cleaning robot... It all depends what kind of robot You build. And don't stop at mapping, there are speech chips, cameras, lots of other cool stuff to add to your robot! Don't spend too much time calculating a goal, have it chose a goal from a list of possible goals or You give it a goal!
Title: Re: choosing goal suggestions (mapping)
Post by: benji on March 25, 2008, 04:16:42 PM
its not time i can change my robots objectives,, ;)
i just want it to map an area with a good manner,, my A* works just great
so my goal now is mapping,help me choose my next goal
then i m goin to make this bot be happy or sad,,, thnks
Title: Re: choosing goal suggestions (mapping)
Post by: Ro-Bot-X on March 25, 2008, 04:23:20 PM
Hmm, you should borrow my doughter... With her around, your robot will never finish mapping so there will be no need for another goal... I mean she spreads her toys and other objects around so fast... I need to make my robot colect everything it's not suposed to be on the floor... Hey, is that a way to find your next goal?
Title: Re: choosing goal suggestions (mapping)
Post by: benji on March 25, 2008, 04:28:39 PM
problem is my robot cant pick nothing of the floor , so it wont do with your daughter....
mine just walks(a hexapod)
our ONLY goal is to draw the map of the room on the pc
so i know when i would halt my algorithm(thats when i find no possible ways to unmapped areas)
then i would know that im inside a closed line of obstacles(a WALL !!!)
the only thing i miss is where do i go after taking the first scan
as i wrote before i tried this little cost thing but it takes time,i need another inteligent choice,with less time this time ;)
Title: Re: choosing goal suggestions (mapping)
Post by: Admin on March 30, 2008, 10:46:30 AM
When you have A* fill in the map, have it start at a different corner of the map each time.

There are some combinations of start and end goals that can take forever if you start the map fill at the same location each time.

For example, when checking each square, don't just start at the top left corner each time. Start at different corners.

edit: I encourage you to post code when you're done ;D
Title: Re: choosing goal suggestions (mapping)
Post by: benji on March 30, 2008, 11:59:48 AM
Admin,, A* starts at the robot square and it spreads out into all directions in the area