Scheme-it

This reference design is a wireless USB gesture input system that enables a person to use a computer by performing intuitive hand and finger motions in the air. While wearing a glove controller on the right hand, the user can move the cursor by forming a pointing gesture and click by curling the index finger or thumb. Other right hand gestures enable scrolling and provide access to various keyboard shortcuts. Wearing a glove device on the left hand allows the user to type different keys through a combination of tilting the hand and touching different portions of the palm and fingers with the thumb. The left and right controllers are attached to each other but communicate to the computer wirelessly through a base station. Mister Gloves uses a low-speed USB 1.1 interface and does not require the installation of additional drivers. Freescale Semiconductor's MMA1260D, MMA2260D and FXLN8361QR1 accelerometers are used in this design. These sensors measure acceleration due to gravity in the Z-axis and X-axis, respectively, and give an analog output. These sensors are aligned such that their acceleration vectors are orthogonal and both lie in the plane of the left hand. Pointing the acceleration vector towards ground results in a higher output voltage and vice versa. This design is applicable to commercial products, hobby projects, and other fields that involve gesture recognition.

The self calibration mode has been added to allow for easy calibration without a special software tool running on the host; Press and hold the calibration button on the device for at least three seconds until the green LED turns off. The yellow calibration LED will then start blinking once a second to indicate that step one of the "self calibration" is in progress. Hold the device "flat" and press the calibration button again within 15 seconds. The yellow LED will start flashing twice each second to indicate that this was successful and that the second step of the calibration is to be performed. Tilt the device 90 degrees to the right and again press the calibration button within 15 seconds. The LED will start blinking three times each second. Tilt the device 90 degrees down and once more press the calibration button within 15 seconds. The LED will start blinking four times each second. Press the calibration button one last time within 15 seconds to permanently store the new calibration data inside the sticks internal EEPROM memory. The yellow LED will stop flashing and the green LED will turn on again. Calibration is done!

The accelerometers used on the device need to be calibrated in order to get accurate measurements in the range of -2G to +2G and to adjust the layout of the two axes to e.g. cope with the fact that the device may be oriented differently when attached to different host computers. The device can be used in conjunction with any software that can be controlled using a simple two axis joystick with two fire buttons, however, the device is not a joystick.