QiMessaging for Smalltalk.

Proof of concept of a pure Smalltalk implementation of QiMessaging based on this description of the protocol.

QiMessaging is the network protocol used to communicate with NAO robots.

This is tested on a NAOv4 robot, minor changes might be required to communicate with a NAOv5 or a Pepper robot.

Installation

Install it on Pharo with:

Metacello new
    repository: 'github://lugu/QiMessagingSmalltalk';
    baseline:'QiMessaging';
    load.

How to start

Update the IP address of the robot accordingly bellow.

How to call a service

| session tts motion |
session := QiSession new join: 'tcp://192.168.0.1:9559'.

tts := session service: 'ALTextToSpeech'.
tts say: 'Hi!'.

motion := session service: 'ALMotion'.
motion moveTo: 1 with: 0 with: 0.

In this example, QiSession>>jon: connects and authenticate wiht the service directory.

Then QiMessaging>>service: reaches out to a service to fetch its description. Using this information a Smalltalk class is created on the fly (ex: QimProxyALTextToSpeech) with all the methods (and signals) of the service.

The messages say: and moveTo:with:with: are remote procedure calls.

How to listen to a signal

| session cancelable |
session := QiSession new join: 'tcp://192.168.0.1:9559'.

session directory enableTrace: true.
cancelable := session directory onTraceObjectDo: [ :each | each traceCr ].
10 timesRepeat: [ session directory services ].

cancelable cancel.

This example uses the service directory. Notice session directory does the same thing as session service: 'ServiceDirectory'.

To listen to the signal called "traceObject" we use the message onTraceObjectDo:. The block passed as an argument will be invoked each time an event is raised by the signal.

To produce some events, we enable tracing and make some calls to the service. We do this because this example is about listening to the "traceObject" signal, other signals don't requires this.

Finally, we cancel the signal registration with the cancel message.

How to list all the serivces on the robot

The list of services can be printed with:

session directory services collect: [ :each | each name traceCr ].

Remember, to see the API of a service, you have to connect to it first with session service:. This will create a class with the prefix QimProxy that you can inspect afterward.

Dependency

Petit Parser is installed as a dependency.