Status of development

[Tobias Opitz]

Hi NXT_ROS-Users,

I started to catkinize the nxt_ros package (https://github.com/ToPitz/nxt_ros_catkin). Until now, it's functionality hasn't been tested (but it builds using ros groovy).

Right now I'm imporving my Python skills for a better understanding of the package. Afterwards I'm going make a full test of it.

[Maximilian Sieber]

Hi,

I'm not familiar with catkin, but I checked the github repo, any way.
I saw that the python code still contains the (mostly obsolete?) nxt msgs.
I replaced most of them with std_msgs. Are you planning to keep the nxt ones?
If not, I still could send a pull  request, which shouldn't affect the catkinization.

The main problem is still the bad performance of the Motor Controller of the old 1.2.0 version of http://code.google.com/p/nxt-python/ , on what our ROS package is based. (sensors are good)
Will someone have enough time to Port the Motor driver of 2.2 to this ? Sadly I don't have any time at all (and no Idea what everything has to be done, to achieve this)
Without this driver, everything will be useless.

regards,
Max

P.S: this is basically what I said on answers.ros, just wanted to have it here

[Tobias Opitz]

Hi,

I haven't thought about changing the nxt_msgs to std_msgs. But it's
worth to think about it. So send a pull request...

I have started to migrate the nxt-python from 1.2.2 to 2.2.2. This works
for the sensors, but I didn't touch the motor interface yet because it
seems to be way more complex.

Luckily Linus Atorf, who has analyzed the motor interface in detail, is
sitting two days away of me... So I went over and had a little chat. He
told me that there is another file which has to be moved onto the brick
to use the new interface.

Due to the fact that I have a little time available and I am able to ask
Linus for help, I will work on the motor interface in the next few days.
I keep you posted on this.

Ciao,
Tobi

[Maximilian Sieber]

I just took a look at my old code, I only changed the Sensor msgs for compatibility with rviz. All the nxt error handling and I2C stuff is the same.
There has to run a motor controller on the nxt itself (It was tricky to drive my robot). Right now, the motor values are set in software, and are not controlled.
I think the 2.2.2 has an PID!!! Controller in nxc or something and python talks to it, instead to the motors.
If you can port this, the nxt is a ROS-worth robot again!!
Got to merge my separate repos somehow. then I'll send the pull request.
What has changed with the sensors? Which ones are supported now?
It is also possible to use a phone with ros android sensor node (Playstore). Someone familiar with pose estimation?
The nxt_assisted_teleop also requires a gyro, might work.