Web Trends & Culture: March 2015

The term motion control in the context of using the human body is the ability to translate body movements into digital signals that is then represented to the user via a feedback of visual display or other means (haptic, auditory, mechanical movement, etc..) but for this article we will be looking at devices that translates movement into visual feedback via a TV Screen.

Le Stick (Mercury Switch)

Motion controllers are not a modern concept as the first commercially available controller that translated movements into control signals was the Le Stick released by DataSoft back in 1981 for the Atari 2600 and Commodore 64. This technology used a mercury switch that would react to the movement of the user but had issues with the movement mechanics as any slight movements would be translated to the console.

Unfortunately due to the devices high price tag of $40 ($108 in 2015), lack of games to take advantage of the technology, accuracy issues and the video game crash of 1983 ended the Le Stick for good.

Nintendo Power Glove (Ultrasonic)

Next up was Nintendo and its Power Glove released in 1989. This device used ultrasonic technology to track movement of the Power Glove. The glove had two ultrasonic transmitters attached and three ultrasonic receivers around the TV screen. The receivers triangulated the transmissions from the glove to determine the X, Y, Z of the glove.

The Power Glove was more of a gimmick than a useful controller plagued with its inconsistent accuracy and lack of game support. Only 100,000 units were sold and was a commercial flop.

Sega Activator (Infrared)

Sega tried its luck with a hands free device known as the Sega Activator which used beams of infrared light emanating straight up from 8 points on the device that would detect the user breaking the beam and translate the action as if the user pressed a button on a conventional controller.

In theory the technology was sound but in practice it was a commercial disaster with a non consistent reaction to players gestures.

It wasn't until the mid 2000's onward where there would be successful motion controllers that actually worked for the user.

Nintendo Wii (Accelerometers + Infrared + Bluetooth)

Where the Power Glove failed the Nintendo Wii's control system succeeded with the combination of accelerometers and infrared technologies to detect the user's gestures. Released in 2006 the Nintendo Wii was a commercial success with their console systems struggling to keep up with the demand.

The key selling point was the novel idea of a motion controller to play the games which broke away from the traditional gaming pads.

The motion controller is connected via Bluetooth to transmit the inputs from the push buttons and the accelerometer combining an infrared signal sent from the controller and is picked up by a receiving bar on top/bottom of TV screen. The controller also contains a small speaker and haptic feedback for additional feedback for the user.

With all these technologies combined enables the user's gestures to be accurately translated onto the screen.

The Microsoft Kinect (RGB Camera, Infrared, Microphone)

The Kinect was released by Microsoft in 2010 for the Xbox 360. This device translates a persons body movements without the need of a controller as the user's body language is the controller.

The device has an RGB camera, an infrared depth sensor and a multi-array microphone. The combination of these technologies provide a full body 3D motion capture which has facial recognition and the use of voice commands. The Kinect was a commercial success partly due to the accuracy of the technology compared to the failure of the Sega Activator which did not come close in the response time. This is an example of how the motion technology has advanced compared to the early 1990's.

Sony PlayStation Move (RGB Camera, inertial sensors, Bluetooth)

Sony's attempt at a motion controller was released in 2010 and received positive reviews. The device uses several technologies to achieve the goal of translating the user's movements into digital signals. The system has a wand controller with a camera that sits on the top/bottom of the TV screen that watches the movement the wand using the LED coloured spear at the end (Up to 4 wand controllers can be used at the same time).

The wand controller is connected to the PlayStation via Bluetooth transmitting data to and from the controller. Within the controller are a pair of inertial sensors, a three-axis linear accelerometer and a three-axis angle rate sensor this is so that the system can track rotation as well as the overall motion the user performs. There is also an internal magnetometer for calibrating the controllers orientation against the Earth's magnetic field and an internal temperature sensor to adjust the inertial sensors against magnetic and temperature factors. Another useful aspect of the inertial sensors is that if the camera is unable to track the LED at the end of the controller (The user blocks the line of sight) then the other sensor readings compensates where the controller is positioned. The wand also has haptic vibration for user feedback.

Leap Motion (Infrared)

Here we have the new kid on the block that specialises with hand motion control. Similar to Microsoft's Kinect using the full body as a way to control movements the Leap Motion uses a high sensitivity system that translates the motion of the hands and finger with great accuracy.

This small device is connected via USB to a Windows/Mac OS computer placed on a desk in front of the user. Using two monochromatic infrared camera and three infrared LEDs, the device observes a hemispherical area above the device where the user hovers their hands over to a distance of around one meter. The LEDs generate a 3D pattern of dots of infrared light which the two camera capture at around 300 frames per second of the reflected light bounced off the user's hands. Using this data and a complex mathematical algorithm the system can use the hand gestures at an individual finger accuracy with a fast response time and display the results on screen.

The Leap Motion is still an experimental piece of equipment and is mostly for developers and tech enthusiasts.

Conclusion

In this article we covered a few motion controllers past and present. With each generation there is an improvement from previous systems, learning from the mistakes and using the feedback of the user to improve the next generation. The Microsoft Kinect and Leap Motion has proven that the use of a physical controller is not necessary to manipulate the virtual world as combining voice commands and body tracking technology can allow the user become immersed in the virtual word plus with the addition of virtual reality goggles/glasses and the availability of 3D screens will bring the user one step closer to feel like they are in another world.