Sorry Eitan! I should have sent everything compressed the first time! I compressed the pkg. To run it just put it on your ROS_PACKAGE_PATH, roscore, roscd roomba_stage and then open stage, launch move_base and open rviz (also sending a roomba_stage.vcg file): rosrun stage stageros roomba_lse_arena.world roslaunch roomba_stage move_base_lse_arena.launch Just send the robot to the top right corner and it will likely stall on the wall. Anyways I just downloaded navigation_experimental! So dwa_local_planner seems to be a lib, how should I use it to get the robot up and running with it? Just give me some quick pointers. Cheers, Gonçalo Cabrita ISR - University of Coimbra Portugal On Thu, Nov 18, 2010 at 7:02 PM, Eitan Marder-Eppstein < eitan@willowgarage.com> wrote: > Gonçalo, > > It looks like you missed a file called "arena_obstalces.pgm" in what you > sent which is needed by the roomba_ise_arena.world file. Is there any way > you can just tar up the package you use to bring things up? Ideally this > would include all the configuration files and launch files you're using to > bring up stage and the navigation stack and would save a bit of grief in me > recreating the same package on my end. > > Thanks a bunch, > > Eitan > > 2010/11/18 Gonçalo Cabrita > >> Hi Eitan! >> >> Thanks for your reply. >> >> I'm attaching the files needed to run the sim on Stage. It is the same >> setup we have on the real arena right now, and the results on the real robot >> are pretty similar to the simulation. >> >> I'll most definitely take a look at the experimental nav stack. I'd like >> to try the dwa_local_planner on the roomba to see what happens! I'll be >> posting some feedback and most likely a bunch of questions! >> >> Gonçalo Cabrita >> ISR - University of Coimbra >> Portugal >> >> >> On Thu, Nov 18, 2010 at 5:54 PM, Eitan Marder-Eppstein < >> eitan@willowgarage.com> wrote: >> >>> Hey guys, >>> >>> So, to join in the discussion. From the video, it looks like the >>> base_local_planner gets stuck in a local minimum with the parameters >>> configured as they are. Is there any way that you can post the package used >>> to create that video so that I can play around a little bit? I've wanted to >>> have a case in simulation where a diff drive robot behaves badly and it >>> seems like this is a simple one that could help me track down some issues >>> the navigation stack has with diff drive robots. With that said, its true >>> that no one local planner is going to fit all robots. >>> >>> We've started development of some other local planners in the >>> navigation_experimental stack that might also be worth checking out. One is >>> called dwa_local_planner and is a much cleaner version of the >>> base_local_planner that includes things like scaling the robot's footprint >>> based on speed, allowing for holonomic robots to explore more of the y >>> velocity space, and exposing parameters via dynamic reconfigure to make >>> tuning them a lot easier... we're testing it on the PR2 right now, not sure >>> how it'll work on a diff-drive robot. There's also the pose_follower which >>> attempts to follow a plan exactly, stopping in the presence of obstacles. >>> This also hasn't been tested on diff-drive robots and I'd expect it could >>> use a few tweaks to really work well, but it might be something to look at. >>> One thing to keep in mind with all this, however, is that the packages in >>> navigation_experimental are, well, experimental, so you're likely to run >>> into some issues from time to time, there are no guarantees about API >>> stability yet, and documentation isn't great. >>> >>> Hope all is well and please do post the simulation package as I'd love to >>> take a look at things, >>> >>> Eitan >>> >>> 2010/11/18 Gonçalo Cabrita >>> >>> We've been a bit busy porting everything that moves around here to ROS! >>>> We'll update our repository in the next week with everything we've got! >>>> >>>> I'm attaching the param files we use for the roombas. >>>> >>>> I'm surprised the creates don't have decent odometry since they were >>>> design for research. We have considered using cheap webcams with visual >>>> odometry to replace the roomba's odometry, but I haven't had time to look >>>> into it. If my memory serves me when we opened a roomba we found a hall >>>> sensor with 4 magnets tied to the motor shaft. So I'm guessing direction is >>>> determined by the motor speed. And that why when you push the roomba the >>>> odometry doesn't count back! >>>> >>>> I'm really interested in solving this matter. If the problem really is >>>> from the nav stack we're in big trouble since everything here is diff drive! >>>> We have roombas, erratics and scouts! >>>> >>>> Gonçalo Cabrita >>>> ISR - University of Coimbra >>>> Portugal >>>> >>>> >>>> On Thu, Nov 18, 2010 at 3:45 PM, Steven Martin < >>>> s34.martin@connect.qut.edu.au> wrote: >>>> >>>>> Yeh I think my problem is related to odometry, the iCreates don't >>>>> have any encoders. I thought they did but after looking closer at the driver >>>>> I am pretty sure its just openloop. Do you have the parameters for amcl in >>>>> your repository? I had a look but couldn't see them anywhere. >>>>> >>>>> I have the code for the pursuit path follower checked in @ >>>>> launchpad.net/cmr but its very incomplete. It will compile, you can >>>>> launch it and it will try and follow a path but it doesn't have any obstacle >>>>> avoidance and I think I have one of my signs wrong in the code as it didn't >>>>> appear to do much following from the very limited testing I have done. >>>>> >>>>> Have a look, its basically as stripped down as I could make a local >>>>> path planner while still fitting in the ROS framework. Also due to the >>>>> pretty well useless iCreate odometry I chose to implement this in the global >>>>> frame and this may have some adverse affects if you are only running >>>>> localiser @ 3Hz. >>>>> >>>>> I will probably have time to look at this next week but I think this is >>>>> a problem for anybody using nonholonomic robots with the Nav Stack so I >>>>> would be surprised if someone else hasn't already got a better solution. >>>>> >>>>> Steve >>>>> >>>>> ------------------------------ >>>>> *From:* ros-users-bounces@code.ros.org [ros-users-bounces@code.ros.org] >>>>> on behalf of Gonçalo Cabrita [goncabrita@gmail.com] >>>>> *Sent:* Friday, 19 November 2010 12:52 AM >>>>> *To:* User discussions >>>>> *Subject:* Re: [ros-users] Navigation Stack on tight places >>>>> >>>>> Hi Steven! >>>>> >>>>> "ts not a failure case but do you also see the one where it turns a >>>>> little bit away from the path then does loop around to rejoin it.?" >>>>> >>>>> You we also get that a lot! The robot never sticks to the path the >>>>> planner outputs, it wonders around a lot. >>>>> >>>>> We are using Roombas 560 with Eee PCs and Hokuyo lasers. We launch >>>>> the Roomba the laser and the tf broadcaster on one file and map server, amcl >>>>> and move base on another one. We have the map updaters running at 3Hz and >>>>> the path planner at 5Hz. Still sometimes the EeePC skips a loop! >>>>> Furthermore, I dunno how the Create is but our Roombas have nasty odometry! >>>>> The encoders have only 1 channel with 4 pulses per motor turn! >>>>> >>>>> Anyways, I'm not familiar with the nav stack code, but I would like >>>>> to help if possible! >>>>> >>>>> Gonçalo Cabrita >>>>> ISR - University of Coimbra >>>>> Portugal >>>>> >>>>> On Thu, Nov 18, 2010 at 2:35 PM, Steven Martin < >>>>> s34.martin@connect.qut.edu.au> wrote: >>>>> >>>>>> Yep see that one all the time. I think the implementation of DWA is >>>>>> flawed for tank steer robots. >>>>>> >>>>>> Its not a failure case but do you also see the one where it turns a >>>>>> little bit away from the path then does loop around to rejoin it.? >>>>>> >>>>>> I started implementing just pure pursuit path follower to replace DWA >>>>>> but haven't quite got it working and been too busy with other stuff. I think >>>>>> we need to implement some other local planners or just path followers. >>>>>> >>>>>> Also what are you using for the localization? I haven't been able to >>>>>> get AMCL to work reliably on the iCreates. >>>>>> ------------------------------ >>>>>> *From:* ros-users-bounces@code.ros.org [ >>>>>> ros-users-bounces@code.ros.org] on behalf of Gonçalo Cabrita [ >>>>>> goncabrita@gmail.com] >>>>>> *Sent:* Thursday, 18 November 2010 11:51 PM >>>>>> *To:* ros-users@code.ros.org >>>>>> *Subject:* [ros-users] Navigation Stack on tight places >>>>>> >>>>>> Hi everyone! >>>>>> >>>>>> We've been using the nav stack on our Roombas for quite a while now, >>>>>> mostly on the corridors of ISR without any problems. >>>>>> >>>>>> However we have a small 4mx3m arena we built specifically for >>>>>> testing odor search algorithms in which we recently started to run some >>>>>> experiments. We quickly found out that the nav stack has some problems >>>>>> moving the robot around in tight places. Quite often we get >>>>>> the behavior that can be seen in the following video... >>>>>> >>>>>> http://www.youtube.com/watch?v=vy9xoNvmktg >>>>>> >>>>>> In the video we are running a Roomba inside our arena in Stage with >>>>>> perfect odometry. The robot stalls against a wall and stays there for >>>>>> 30mins until we stop it. On occasion the robot eventually gets out after a >>>>>> while. >>>>>> >>>>>> At first I thought this could be happening because of the poor >>>>>> performance of the EeePCs the Roombas carry around or because of the >>>>>> Roomba's crappy odometry, but in Stage on a Core2Duo laptop we were able to >>>>>> see the same behavior. >>>>>> >>>>>> Has anyone experienced this behavior before? >>>>>> >>>>>> _______________________________________________ >>>>>> ros-users mailing list >>>>>> ros-users@code.ros.org >>>>>> https://code.ros.org/mailman/listinfo/ros-users >>>>>> >>>>>> >>>>> >>>>> _______________________________________________ >>>>> ros-users mailing list >>>>> ros-users@code.ros.org >>>>> https://code.ros.org/mailman/listinfo/ros-users >>>>> >>>>> >>>> >>>> _______________________________________________ >>>> ros-users mailing list >>>> ros-users@code.ros.org >>>> https://code.ros.org/mailman/listinfo/ros-users >>>> >>>> >>> >>> _______________________________________________ >>> ros-users mailing list >>> ros-users@code.ros.org >>> https://code.ros.org/mailman/listinfo/ros-users >>> >>> >> >> _______________________________________________ >> ros-users mailing list >> ros-users@code.ros.org >> https://code.ros.org/mailman/listinfo/ros-users >> >> > > _______________________________________________ > ros-users mailing list > ros-users@code.ros.org > https://code.ros.org/mailman/listinfo/ros-users > >