Initial pose setting problem

[Lilly-yang]

Hi,

I am currently studying Navigation Tutorial. I failed to set the initial posture of the car on the map. It will always change automatically. (Here are the screen vedio and real scene)

And (maybe because of the initial pose problem) I also can't set the goal pose.

Could you give me some suggestions on why it happened and how to fix it? Thank you!

[schmittlema]

So after taking a look at the video it looks like your map doesn't line up with the room you are operating in. The navigation tutorial relies on mushr_pf which is a particle filter. The particle filter uses the laser scanner to localize (moving dots in your video). Basically it tries to match the current laser scan with the map of the environment. And since your map is of the track and not the room, the particle filter does not localize. To build a map of the room try out our new tutorial on map building .

I'm assuming you are using the track map so that the rhc controller stays within the path. That makes a lot of sense, but you will need to have a separate map for localization (following the mapping tutorial) and for control (your current map) in order for it to work. So you will want to publish both maps with separate map_servers. This can be done by running rosrun map_server map_server PATH_TO_YOUR_MAP.yaml for each map. You will also need to have separate map topics so that your two map servers don't both publish to /map. See here for how to do that. And finally, mushr_rhc and mushr_pf need to be told to subscribe to their associated map. You can change the map topic for mushr_pf here, and you can leave mushr_rhc's map_topic to the default /map. Appologies that these topic names aren't parameters, that is on the todo list.

[schmittlema]

awesome, is there anything else causing trouble? I saw you mentioned something about the car sliding in rviz? That would likely be related to the particle filter

[abhisheksreesaila]

Thanks @schmittlema It is sliding. See video attached. but i am able to run the car autonomously.

Pose.estimate.slide_480p.mov

[abhisheksreesaila]

@schmittlema the only major problem i am trying to solve before i take this to street is the battery problem. nvidia jetson switches off after 1-2 min of charging battery. the converter shows 5V, but jetson struggles to keep up. have you guys had any issues with it. VESC and its battery seems fine.

[schmittlema]

Sliding problem:

• The particle filter is trying to localize the car in the map using the laser scan (pink dots) which are coming from the real scanner. It looks like from the scan that your car is sitting in some corner. So when you try to localize it to another part of the map it will move untill it finds a spot that looks like the corner the real car is sitting in. Could you try setting the 2D pose estimate near the corner the car is truely in? I would also try to roughly match orientation.

Vesc problem:

• Let's open up a new discussionn for this as it does not pertain to navigation. We can certainly help you from there.

[abhisheksreesaila]

Understood. Yes the car is sitting the one corner connected to the power source since the battery is not working as expected.