Affordable Motion Capture at Home
Microsoft Kinect v2
Technology has made things more convenient and affordable with fancy devices that keep coming out into the market that are more mobile than models from previous years. Motion capture is now possible in your living room with just a few hundred dollars. That still might be high for some, but if you compare motion capture a couple of decades ago it will really put things into perspective. And cost cannot beat a setup that can fit in your living room, the convenience is just too good to turn down.
Cost
A very basic motion capture setup requires a depth camera, a PC, and software that is compatible with the respective camera. This might come as a surprise, but the most costly part would probably be the software if you want production level quality out of the box. If you are ok with decent quality then the camera may cost the most for your setup.
Open Source Software (Blender rant)
Blender with Motion Capture Plugin using Kinect (Nimate, plugin)
Blender should be the first thing that comes to mind when on the topic of open source 3D software. It is probably the most comprehensive free software for 3D computer graphics. Blender can do it all, not just manipulating 3D geometry, Blender can do compositing, animation, rigging, procedural scripting in python, CAD, high quality rendering, node based material workflow, and a bonus it has a built-in game engine. The game engine isn’t very popular though, because it’s not portable outside of Blender, so if you release your game made with the engine, you need to ship it with the entire Blender software.
Mocap Open Source
A free Mocap plugin for Blender is available that I have used and still occasionally turn to for a quick animation.
It only works with Windows 10 and Blender 2.79 currently. But it is a very capable software. It might not deliver the high quality production right out of the box, but it comes very close and it’s free! So this can be a very good entry level for those trying out the mocap world to see if this is interesting. You can always add more plugins to enhance the features and tweak Blender to suit your needs, but this will require some research and hacking.
Kinect v2 on a tripod
Depth Camera
The Kinect has aged very well. Microsoft doesn’t produce many products that I really enjoy using, but the Kinect should be something they definitely can brag about. It first came out in 2010 for the Xbox and it was very advanced for its time back then. Then in 2012 Microsoft released the 2nd generation for the Kinect which is the one I own.
The SDK for the Kinect is probably the best part of the Kinect allowing coders to hack as much as they want. To this very day (at the time of writing this post) the original first two generations of the Kinect is still being used for many different projects and motion capture is just the tip of the ice berg. From autonomous R/C cars to robotic arms, the Kinect was used in a lot of projects for professional research purposes by the many educational institutional staff. University professors were using it in their research projects because of the awesome SDK and precision of the device (at the time).
My 2nd gen Kinect bought online used was in very nice condition. If it wasn’t labelled as “used”, I seriously wouldn’t be able to tell. Unfortunately Microsoft discontinued manufacturing the Kinect and all the accessories, so consumers need to resort to after marketplaces to get home-made cables for the Kinect. The original packaging of the Kinect doesn’t come with USB cables for the PC, because it was originally intended for the Xbox exclusively until Microsoft realized the hacker community was obsessed with it. So you need to buy a special cable for the Kinect to work with the PC. It’s an adapter that links the Kinect to the PC through a USB 3.1 plug. So the PC needs to have a USB 3.1 peripheral plug or you can always buy a PCI USB 3.1 card on Amazon and upgrade the PC. I’m not sure what you would do for laptops though.
Kinect Market
Today we have a lot more choices, but at the price point of the Kinect, there aren’t many that can compete with the price. Even after the Kinect market started jacking up the prices after Microsoft announced the discontinuation of production, it is still the most affordable and most compatible device for motion capture at home. A lot of commercial motion capture software still require the use of the Kinect for live mocap recording.
The Amazon item shown on the right is the Kinect that I bought USED. It’s used because Microsoft discontinued the product many years ago and the only way to get the Kinect now is through the refurbished market.
The links on the right are Amazon affiliate links.
Kinect Adapter Cable for PC
You also need a special cable that will allow a Windows 10 PC to communicate with the Kinect. This cable is absolutely necessary to capture and record the motion to a 3D application on your PC.
The Kinect Adapter cable Amazon item shown on the right isn’t the one I bought, but it’s the same type of cable. The one I bought hasn’t been in stock for awhile now, so I have added a different Amazon item link.
Unlike the Kinect device, Adapter cable is brand new, but is NOT manufactured by Microsoft. Microsoft does offer an Adapter cable with Microsoft’s name slapped on the box, but it’s insanely expensive. Especially now that they discontinued the Kinect, it’s even more expensive, almost half the cost of the refurbished Kinect device! So I recommend getting the Kinect Adapter from other manufacturers, like the one from the Amazon link on the right.
Kinect Captured Animation
As a test, I used the Kinect to capture some random movements and transferred the motion to a very simple mannequin 3D model. I then added some simple particle effects in Blender. The particles are constrained one hand of the mannequin. The clip was done a long time ago so the special effects is quite simple. But the main idea was to test the Kinect for motion capture in action.