Had an exciting day friday! got to play with the motion capture suite!!!! Ben kindly said he would ware it for me, so thanks to Ben Mayfield for taking the time out to do it, also it wasn’t the most comfortable of equipment. I did my best to right down notes and take everything in so i’m writing up what i have and what i remember, please bare in mind this is my first ever go with motion capture.

The suite is a Gypsy 6 exoskeleton from Animazoo.

The software Gypsy Sphinx comes with the suite.

The data is transmitted from the suite wirelessly to a radio receiver. It uses gyroscopes for working out the angle of movement.

Before the start you need the calibration cube.( Also known as a jigg)

This Calibration cube is a know quantity to the program, it knows how tall, deep and wide the cube it.

Then we get ben to stand in it and take a photo from the front and his right.

From this the software can tell how tall Ben is and calculate other measurements. When we imported these pictures the computer wasn’t having a great time calculating Ben’s data. But a quick levelling and crop in Photoshop sorted that. He needs to have his arms by his sides as a default stance. Then in the software you upload the actor file (photos) and tell the software what it the back left corner, top right corner, bottom right …etc by using the balls on the calibration cube. Unfortunately I didn’t have a screen shot so I quickly drew this on ben to demonstrate what it looked like. You then put the corresponding joints in place .

The right side of the actor is the green side of the skeleton. Always the right side of the actor! Once all the joints are in place you store the actors file. This means Ben has been calibrated! his hight and distance and position of the joints have been calculated and stored.

In my notes I have written down that the resistance valve works off the numerical data recorded from the rotational value of the joints. These resistance valves are on the joints of the suit on positioned on the actor. By measuring the degree of movement within these resistance valves and the gyroscope the software can work out where the actor is in 3D space and the slightest of movement.

I can’t remember the part of the program you open but you load the calibrated actor data to this live window and from there you need to set north. This tells the computer the default position of the actor and brings it back to the centre of the field. Then hit record and the actor can perform what is needed. Once finished stop the recording and save as a BVH file ready to open in MotionBuilder.

Advertisements