Phidget handler (phid://)

Background

Phidget is a company that provides products for USB Sensing and Control. Phidget specialize in making affordable, easy to use sensors and controllers that require minimal electronics knowledge. Phidget covers vast range of sensors and motors.

Sensors

• Distance
• Encoders
• FSR
• Gas Pressure
• Light/Sound
• Load Cells
• Motion
• pH/ORP
• Potentiometers
• Proximity
• Temperature/  Humidity
• Touch
• Voltage/Current

Motors

• Linear Actuators
• Servo Controllers
• Servo Motors
• DC Controllers
• DC Motors
• DC Motors w/  Encoders
• Stepper Controllers
• Stepper Motors
• Hardware

Phidget Protocol Handler Flow

TQLEngine provides phidget protocol handler, which is essentially a wrapper over the Phidget Driver that is provided by Phidget. Note that the developers are required to install the phidget driver for different platform (Linux, Windows, Mac) from the phidget website.

Phidget Protocol Handler Parameters

Phidget has a broad range of sensors and motors. The phidget protocol handler provides wrapper implementation for following Device Types. Adding support for additional device types will be provided on a need basis.

Phidget Interface Kit

Servo Motor

GPS Sensor

LCD Display

<USBCameraParameters>
  <ImageFormat></ImageFormat>
  <SaveToDisk></SaveToDisk>
  <ImageName></ImageName>
  <Size>
    <Height></Height>
    <Width></Width>
  </Size>
  <Configuration>
    <Standard></Standard>
    <Quality></Quality>
    <Channel></Channel>
    <Brightness></Brightness>
    <Contrast></Contrast>
    <Gamma></Gamma>
    <Gain></Gain>
    <Sharpness></Sharpness>
    <Saturation></Saturation>
    <Hue></Hue>
  </Configuration>
</USBCameraParameters>

USB Camera Parameter Structure

Invoking UCAM Handler

<Action Name="USBCameraImageAction"> <Workflow Limit="1" Live="1" Timeout="-1"> <Task name="Main" while="true"> <Event name="Argument" as="ActionArgument"/> <Invoke name="GetImage" waitFor="ActionArgument" post="ucam://"> <Message> <Value> <USBCameraParameters> <ImageFormat>[%:Event.Argument.USBCameraParameters.ImageFormat.Value:%]</ImageFormat> <SaveToDisk>[%:Event.Argument.USBCameraParameters.SaveToDisk.Value:%]</SaveToDisk> <ImageName>[%:Event.Argument.USBCameraParameters.ImageName.Value:%]</ImageName> <Size> <Height>[%:Event.Argument.USBCameraParameters.Size.Height.Value:%]</Height> <Width>[%:Event.Argument.USBCameraParameters.Size.Width.Value:%]</Width> </Size> <Configuration> <Standard>[%:Event.Argument.USBCameraParameters.Configuration.Standard.Value:%]</Standard> <Quality>[%:Event.Argument.USBCameraParameters.Configuration.Quality.Value:%]</Quality> <Channel>[%:Event.Argument.USBCameraParameters.Configuration.Channel.Value:%]</Channel> <Brightness>[%:Event.Argument.USBCameraParameters.Configuration.Brightness.Value:%]</Brightness> <Contrast>[%:Event.Argument.USBCameraParameters.Configuration.Contrast.Value:%]</Contrast> <Gamma>[%:Event.Argument.USBCameraParameters.Configuration.Gamma.Value:%]</Gamma> <Gain>[%:Event.Argument.USBCameraParameters.Configuration.Gain.Value:%]</Gain> <Sharpness>[%:Event.Argument.USBCameraParameters.Configuration.Sharpness.Value:%]</Sharpness> <Saturation>[%:Event.Argument.USBCameraParameters.Configuration.Saturation.Value:%]</Saturation> <Hue>[%:Event.Argument.USBCameraParameters.Configuration.Hue.Value:%]</Hue> </Configuration> </USBCameraParameters> </Value> </Message> </Invoke> <Log Message="******Invoked USBCamera******"/> <Output name="Result" as="ActionResult"> <Value> <Image>[%:[%:@Output:%]Invoke.GetImage.Message.Value:%]</Image> </Value> </Output> </Task> </Workflow> </Action>

Driver Installation Steps

Installing Phidget Driver

Installing V4l4j

For the ucam handler to work two things are needed, the video driver of the camera which comes by default and the v4l4j library. The steps below show installing of v4l4j library 
Steps:

1.Before installing the v4l4j some packages are needed to be installed. If you are running debian based operating system type the command

 sudo apt-get install openjdk-7-jdk ant libjpeg8-dev
 
It will download and install the required prereqs, 
 

2. To download the v4l4j you need subversion(svn) tool, download and install it as shown below

sudo apt-get install subversion

3. Now download the library using the following command

svn co http://v4l4j.googlecode.com/svn/v4l4j/trunk v4l4j-trunk
 

4. Then go to the v4l4j-trunk directory (cd v4l4j-trunk) and start the build process by typing the command shown below

{}On Raspbian Wheezy (Raspberry pi):
JDK_HOME=/usr/lib/jvm/java-7-openjdk-armhf/ LIBPIXFC=pixfc-sse/libpixfc-sse-armv6l-hardfp.a ant clean all
*On Wheezy beta: (Raspberry Pi)*
JDK_HOME=/usr/lib/jvm/java-7-openjdk-armhf/ LIBPIXFC=pixfc-sse/libpixfc-sse-armv6l-softfp.a ant clean all
On other environments setup
Setup JDK_HOME environment variable to your JDK path and do
ant clean all 
 

5. If you get this error "error: libv4lconvert.h: No such file or directory" , type

sudo apt-get install libv4l-dev 

And do the build process again. 

6. Once the build process is completed

7. Install by running command

sudo ant install
 

8. Finally test the library by running command

ant test-fps