Android + ROS + QR

Question

Hi, I just started with ROS and I want to make an android app that reads a QR code to decide which information it should send. After deciding which information it should send, a node should receive it and do something. The information would be a position in the world.

May I ask how I should start? I don't know the approach I should take: -Should I make a common android app and find a way to send the information? How can I send it to a node without the app being a node? -Should I run a node in the cel phone and send the information via a topic?

I am quite lost because I don't know java and I am new to ROS. Not sure which approach would be easier or better.

Thanks in advance for your help.

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Originally posted by Elvish Champion on ROS Answers with karma: 165 on 2014-04-07

Post score: 0

Answer 1

There is already some code in the rosjava repositories which do this. The zebra crossing - zxing is a library that does the qr codes. A simple RosActivity from android_core should let you build the basis of an app which can publish whatever information you want from the qr code to a ros node on another system. You can grep through the android_apps and android_remocons code to find usage of zxing.

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Originally posted by Daniel Stonier with karma: 3170 on 2014-04-09

This answer was ACCEPTED on the original site

Post score: 1

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Original comments

Comment by Elvish Champion on 2014-04-19:
Thanks you have been a great help. I am running the PubSub app from android_core. The message "Hello World! #" appears in my cell phone since it establishes communication with my pc. However, I am unable to see that message with rostopic echo /chatter . May I ask what am I doing wrong? Thanks.

Comment by Elvish Champion on 2014-04-19:
Using rqt_graph I can see rostpic is suscribed to /chatter in the Nodes/Topic(All) tab. However only rostopic appears in Nodes/Topics(Active). I suppose that the publisher isn't publishing new content to /chatter, but that seems strange since "Hello World! #" keeps increasing. Thanks =)