Creating an object for augmented reality on Raspberry Pi
This is the third article in my series on augmented reality, following:
- Installing an augmented reality app on the Raspberry Pi
- Installing a DHT22 temp and humidity sensor on the raspberry pi
In this tutorial I will create my first object to use in OpenHybrid. This is a rather long process, so let’s start right away.
Setup the augmented reality object
First access the OpenHybrid web interface via web browser. If you followed my tutorial it should be: “your IP Address”:8080.
Now click on the “Create new object” link and enter a name for your object.
I will go for “humidity_pi” for now. Next, click on “Create”.
Now the new object should be visible in the dashboard. Note, that “Add Target” and “Add Interface” have different colors. That means, we have to configure booth of them. If they are configured correctly, they should turn green.
Before we can start to configure our target, we need a target picture. This was a challenge the first time I did this, as I did not know, what kind of picture to use. Browsing trough the documentation I found a link to hrqr.org, which can generate a picture for you. As far as I understand it, you can use any kind of picture or QR code as long as it is recognizable by your camera. But for now let’s stick with hrqr.org.
So go to their website, which should look like this:
Enter some text you like. It does not matter what, as this has no impact on your target picture to work.
Download the SVG Image created and convert this to a JPG File (use any program you like). It will only work if it is a .jpg file, other formats are not supported.
OK, now back to your OpenHybrid dashboard.
Let’s start by clicking on “Add Target”, which should lead you to the following page.
This page has a brief “how to” on the process. But let’s go though it step by step.
- The target source image was already created in the last steps on hrqr.org. So, we can skip to the next step.
- To login to Vuforia Target Manager, you need an account there. If you have no account, you have to create one. Scroll down and the Vuforia Target Manager should be displayed already.
Important: Copy the name written in bold in Step 5.
Click on “Log in”
On the pop-up screen click on “Create account now”.
Now you have to enter you personal account information and klick “OK”. Also you have to confirm your mail address. If you have done all this, you can log in.
You should be directed to the License Manager. Enter an application name you like, select “Mobile” and choose the Starter License Key.
Then click on “Next” and you should have set up your application.
- Next click on “Target Manager” to create you Device Database. On this page click on “Add Database” to create you new database.
In the pop-up menu enter a name for your database and select “Device” as type. Click “Create” to finish the process.
You should end up in the target manager within your database.
Now click on “Ad Target” to create your first target (your humidity sensor).
- On this screen you have to define you target.
First select the type. If you are following this guide select “Single Image”.
Then upload your target picture, you created before on hrqr.org (remember, it has to be a JPG).
As width enter “300”.
The name is important and is the next step (don’t click add yet).
- The name you need here is already defined and was written on the page shown in Step 2. If you copied the name, paste it here and click “Add”.
Now your target should be created.
- Select one single target (not more) and click “Download Database”. The file should be downloaded and stored locally on your device.
When asked select SDK as development platform.
- The last step is to upload your database to your OpenHybrid installation.
To do so, just drag the file in the upper part of the screen or click “Upload Target zip and jpg Files”.
In the official documentation an icon will appear between the two buttons, representing the uploaded file. That did not work for me. The icon was never displayed, but when I clicked on “back” it seemed to work, as both buttons on the humidity_pi where green.
You are done for now – the interface section will be part of the next tutorial.
Let’s test the system.
Testing the augmented reality object
First print the target file picture you created at hrqr.org.
So get out your mobile phone and start “Reality Editor” and click on the settings (that is the lowest icon, a pump or something like that). Activate the developer functions. Your object should show up in the right panel. If so, close the settings by touching the settings icon again.
Now approach your object, pointing the camera at it.
The object (the target picture) should be recognized, as seen in the picture below. A hand drawn bird should be displayed if you did not change anything in the interface section.
Test done! I have to admit, I never thought I get this far :-).
Next is to display the humidity and temperature information. But this will be covered in another tutorial.