Users Manual

7.2.2 Services
The IOControl component offers the following services.
get
_
io
_
values This service call retrieves the current state of the general purpose inputs and outputs. The re-
turned time stamp is the time of measurement. The call returns an error if the rc_visard does not have an
IOControl license.
This service requires no arguments.
This service returns the following response:
{
"in1": "bool",
"in2": "bool",
"out1": "bool",
"out2": "bool",
"return
_
code": {
"message": "string",
"value": "int16"
},
"timestamp": {
"nsec": "int32",
"sec": "int32"
}
}
Possible return codes are shown below.
Table 7.2.2: Possible return codes of the get
_
io
_
values service call.
Code Description
0 Success
-2 Internal error
-9 License for iocontrol is not available
save
_
parameters With this service call, the component’s current parameter settings are persisted to the
rc_visard. That is, these values are applied even after reboot.
This service requires no arguments.
This service returns no response.
reset
_
defaults Restores and applies the default values for this component’s parameters (“factory reset”).
This service requires no arguments.
This service returns no response.
Warning: The user must be aware that calling this service causes the current parameter settings for the
IOControl component to be irrecoverably lost.
7.3 TagDetect
7.3.1 Introduction
The TagDetect components run on board the rc_visard and allow the detection of 2D bar codes and tags. Currently,
there are TagDetect components for QR codes and AprilTags. The components furthermore compute the position
and orientation of each tag in the 3D camera coordinate system, making it simple to manipulate a tag with a robot
or to localize the camera with respect to a tag.
7.3. TagDetect 74