User Manual/2. Setting up the system
Congratulations! If you got here it’s because you have already gathered together all the parts needed to build your motion capture suit. Now is the moment of truth.
In this chapter we will put everything in place and see if it's working correctly. We should check the following functionalities:
- The SBC boots correctly.
The SBC acts as an access point, and we are able to connect to it from a separate PC. The Utility software on the SBC is working correctly.
- The Hub and K-Ceptors are wired correctly and the Notochord is able to talk to them.
Powering the system
To power the system a 5V, 2A supply is needed. It can be connected to the SCB only, or also to the Hub. Both connections use a micro USB-B connector. By far the easiest way to achieve it is to use a common power bank. It should be rated for at least 2A.To have a durable supply a capacity of at least 10000mAh is desirable. Under normal capture conditions such a power bank was able to keep the system running for around 8 hours.
The Chordata Hub has two possible configurations: with or without a separate power source. A jumper on the Hub (JP1) allows you to select between these configurations.
- In the former the power comes from a buck converter on the Hub, that takes a 5V input and delivers 3.3V to the rest of the system.
- In the latter the power comes from 3v3 rail on the SBC.
A 5 volt tension can be applied only via the micro USB connectors on the Hub or SBC
Using the dedicated power source
This is the recommended configuration. The power line from the Powerbank should go to the micro USB connector on the Hub (J12), and from the big USB connector (J11) to the SBC.
To use this configuration the jumper should be positioned connecting the pins #1 and #2 of JP1
Using the 3v3 rail from the SBC
This configuration is mostly used for testing purpouses. The power line from the Powerbank should only go to the micro USB connector on the SBC.
To use this configuration the jumper should be positioned connecting the pins #2 and #3 of JP1
Wiring the Hub and raspberry
Start by wiring the hub and the raspberry using female jumper wires as described in the diagram. Then power the Raspberry. You should see a red led constantly on and a green led blinking, that means that the amount of power provided is enough to keep the Raspberry working, and also that the system is booting.
The blue led on the Hub should stay on as an indicator of a stable power supply.
Connecting the K-Ceptors
Plug one of the ID Modules on top of one of the K-Ceptors, then plug it to one of the gates of the Hub.
Be sure to plug the cable on the
IN --> connector of the K-Ceptor.
Other K-Ceptors can be connected to the output of the previous one forming a chain, always going from
OUT --> to
On a working K-Ceptor the Blue led [D1] should turn on and stay that way.
If you built the hardware yourself and want to know how to test and troubleshoot a K-Ceptor take a look at: Troubleshooting a K-Ceptor
Connecting to the WIFI LAN
In the meantime you can use an external access point as described in this section.
Use an external router or a smartphone hotspot to create a WIFI LAN with the following specs:
- SSID: Chordata-net
- Pass: chordata
The SBC will connect to it on boot.
Testing the system
In a near future, once the Utility software is up and running you will be able to access the system and test it in a much more easy way.
See the Roadmap to check the state of the development.
Run the notochord to test the Hub
On the SBC terminal environment navigate to the folder where the
notochord binary is, and run it. Add the client computer IP ADDRESS as a parameter in order to receive the data.
cd notochord/bin ./notochord <CLIENT COMPUTER IP ADDRESS>
That will run the notochord using the default
Chordata.xml configuration file, which by default reads only one K-Ceptor with a value of 1 from the J1 gate on the Hub.
Chordata.xmlfile contains a description of the Hubs and K-Ceptors connected the SBC. The notochord uses this description in a process called Armature parsing to create an internal representation of the devices to be read, so it should match way the physical devices are connected.
You can learn more about how to describe this hierarchies here.
If you want to change the configuration file for the notochord use the
-c flag. For example, to read a Default_Biped_Configuration you can issue:
./notochord -c ../default_byped.xml <CLIENT COMPUTER IP ADDRESS>
To use the file
default_byped.xml which comes by default when downloading the
If you get any errors there's probably an inconsistency between the configuration file and the way the physical nodes are set. It can also be due to a hardware problem, or a misconfiguration on the SBC. Take a look at the Troubleshooting section on the Notochord page