A rotational mouse is a type of computer mouse which attempts to expand traditional mouse functionality. The objective of rotational mice is to facilitate three degrees of freedom (3DOF) for human-computer interaction by adding a third dimensional input, yaw (or Rz), to the existing x and y dimensional inputs. There have been several attempts to develop rotating mice, using a variety of mechanisms to detect rotation.
Mechanisms using relative measures of rotation: These devices are able to detect that the mouse has rotated by so many degrees, but cannot accurately identify where the rotation started or ended, increasing their tendency to lose orientation.
• 2-balls or 2-sensors
In 1989 we saw the first mention of actually rotating objects on screen by rotating the mouse, with a US patent for a cursor display apparatus, US patent number 4,887,230. This led to a succession of refinements of the 2-ball / 2-sensor mouse concept. Notable examples include:
1. Multi-dimensional input device; US 5,298,919
2. Positioning device reporting X, Y and Yaw motion; US 5,477,237
3. Twin mouse digitizer; US 6,081,258
4. Pointing device having rotational sensing mechanisms; US 6,618,038
5. Multiple sensor device and method; US 6,847,353
Unlike the conventional mouse which senses z-axis and y-axis displacement only, these 2-ball or 2-sensor mice are also able to sense z-axis angular motion, calculated by the two sets of x-y displacement data.
• Mechanical ring & rotary encoder
Within these devices rotation is detected by a mechanical ring (US 5,936,612). This mechanism was promoted by the Canadian company Handview Inc; however it apparently never made it to production.
• Gyroscopes or accelerometers
US Patent 6,130,664, named Input Device was the first known application of gyros to a rotating mouse. However, we still have not seen this technology in a commercial mouse to date.
Mechanisms using absolute measures of rotation
• Tablet/Digitiser Puck
The patent for an Absolute position controller, US 4,814,533, is the earliest know reference to this type of input device. However, it was the patent for an orientational mouse computer input system, US 5,162,781, which suggested using a tablet with a detectable pattern or grid and sensors in the puck for computer navigation.
The Wacom Intuos 4D Mouse puck was the first commercial rotating “mouse.” The product was not a standalone mouse but rather a tablet accessory.
• Compass
The Orbita mouse is the first commercially released non-tablet rotating mouse. Licensed and commercialized by Australian company Cyber Sport, the Orbita is equipped with a patented compass mechanism which solved the problems which plagued earlier rotating mechanisms. The inbuilt compass provides the mouse with ability to detect rotation based on the Earth’s magnetic field so that it can accurately maintain orientation once the ‘up’ direction is specified. The round design makes it completely rotatable, spinning freely on ball bearings, and is usable at any angle due to the ‘push and squeeze’ button configuration encased in a silicone soft shell. The mouse reports rotation as scroll wheel commands so compatible with most applications.
Due to the round shape the Orbita mouse is commonly confused as being similar to the original, circular USB iMac mouse. However, the two mice are functionally different, primarily because the iMac's mouse is not a rotating mouse. The Orbita, unlike the Puck mouse, is designed to be ergonomic, with the round shape lending practical aid to the mouse's spinning action, and is not a purely æsthetic trait.