Rover in GUIDE mode

Oh, sorry, I thought that it’s not working.
Wich version do I have to flash? last master o some beta?

Leonardo,

3.2.1 should work. Rover-3.2.2-rc1 is also available as a beta release but is only slightly different than 3.2.1.
I wonder what it was that made it seem like skid-steering boats wouldn’t work… Below is an image of a skid-steering boat from a user involved in the 3.2.1 beta testing.

If you just need navigation with WP, you don’t need ROS. ArduPilot is already abke to follow WPs mission. Why do you want to use ROS ?

If you want to stick with cmd_vel then you need to find a ros package that take wp as input and output twist message. But that already what ArduPilot does internally…

Well, there is a couple of post concerning to pivot turn tunning problem.
Here Pixhawk 2 tuning help appreciated you say that pivot turn will be solved in rover 3.3.
Anyway, I will try it again with latest firmware and report back on another post.

Thank!

I’m working on a cooperative control between a UAV and an ASV. This kind of control will be running on ROS.
Right now I’m making my first steps working with ASV. WP navigation with APM will be a nice feature to add and show an intermediate work. But I will need to command the ASV by ROS soon.
Right now I have a RP3, connected to Pixhawk, running ROS and could make a map (using hector mapping) of some part of stern coast. But driven in manual mode.
So both help will be apretiated!

I will try to start testing guided and cmd_vel with just publishing to cmd_vel topic. I will report later.

Thank!

If you get map, just use a global planner to feed ardurover with wp in local coordinate, or a local planner with cmd_vel. You don’t need laser to use ros nav stack, it is use if you want to avoid obstacles.

if I run
rostopic pub /mavros/cmd_vel_unstamped geometry_msgs/Twist -r 10 – ‘[0.5,0.0,0.0]’ ‘[0.0, 0.0, 0.0]’ with my boat in GUIDE mode, it will move forward at 0.5 m/sec, right?
So, I will need to tune Speed control (http://ardupilot.org/rover/docs/rover-tuning-throttle-and-speed.html) right?
The same for
rostopic pub /mavros/cmd_vel_unstamped geometry_msgs/Twist -r 10 – ‘[0.0,0.0,0.0]’ ‘[0.0, 0.0, 0.785]’ it will make my boat turn at 45°/sec and it will need that I previosly tune APM for steering (http://ardupilot.org/rover/docs/rover-tuning-steering-rate.html) right?
So, those 2 controller are enabled in GUIDE mode. Am I right?

Thank!

BTW the correct sintax for the topic published is:

rostopic pub -r 10 /mavros/setpoint_velocity/cmd_vel_unstamped geometry_msgs/Twist ‘{linear: {x: 0.1, y: 0.0, z: 0.0}, angular: {x: 0.0,y: 0.0,z: 0.0}}’

This works on my boat.

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I’ll have to leave the ROS question for @khancyr to answer but for the speed tuning question I think the answer is “yes”, you’ll need to tune it using the web link you’ve provided. Tuning the speed controller is relatively easy, the most important part is getting a good cruise-speed and cruise-throttle value and that can be done easily using a ch7 option as mentioned on the wiki.

Hey Leonardo ,

I’ll get back to you on this soon. I’ll speak to one of our software engineers who is currently working on this. I’m currently travelling

Auto mode is working ok now in my boat (Success tunning for Auto mode)
So I have now a long way working with my boat with ROS.

Auto mode gives me the chance to make several experiments, but the final goal of my reserch needs the ASV to be controlled with ROS. So I will be using this post to share experiences on Boats and ROS.

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Do I need to start mavros before power up pixhawk?
I found that launching MAVRos after pixhawk boots, then mavros don’t start. is it ok or it just happened to me?

Thank

It shouldn’t matter…
what error did you get ?

it does not show any error, but it seems to hang waiting for FC.
The last INFO I get is MAVROS started. MY ID 1.240, TARGET ID 1.1

I wait for a minute or so, if I reboot pixhawk, in that moment, then mavros continue starting.

As a side note, I wonder if someone could raise a PR with mavros to get the external position plugin removed from the blacklist (or added to the whitelist?)? The PR to add support to ardupilot should go into master tomorrow.

Ok, mavros is working ok now.

Does anyone knows a ROS package that takes google maps waypoint (lat lon) and current position and send commands (cmd_vel) to the rover to navigate? supposing that there is no obstacles between Rover and WP?

Thank!

the PR to add support for the external position mavlink messages has gone into master now. It will probably take a few hours for the autobuilder to complete building it and then the latest firmware can be loaded using the mission planner’s install firmware screen’s magic Ctrl-Q feature. You should see the version name under the vehicle icons change to xxx-dev.

If anybody could give this a test that would be really great. We’ve tested it in the simulator but not with ROS.

Modification on Mavros submitted !

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can you explain a little more this feature?
I think I could test it this week (I’m planning some experiments on the stearn this weekend).

Thanks @khancyr.

I forgot to mention that this change has only been made to the EKF2 for now. EKF3 will come in the near future.

@Leonardo,
This makes it easier for external systems (like ROS) to send in external position estimates and have the EKF consume them. Good for non-GPS environments.