Tactile Stimulation & Three Dimensional Position Extrapolation

Augmented interfaces for improved situational awareness

Ethan White, PhD Presented to Defense Advanced Research Projects Agency

(DARPA)

Advances in augmented reality allow modern warfighters unprecedented battlefield awareness.

The majority of VR enhancements utilize the visual stream to convey information. While this is extremely fast, we have limited visual band-width.

Additionally, particular types of information are better suited to tactile interfaces.

Humans have an innate ability to extrapolate the relative position and movement of objects from comparatively few cues. Stereoscopic vision and binaural hearing are extremely sensitive, accurate, and cognitively light (they do not demand much conscious attention).

Our brains are hard-wired to deduce such information autonomically even for hundreds of moving stimuli.

A common difficulty for the warfighter is movement of squads in environments where line of sight is occluded. Soldiers can be separated from their fire teams, become lost, disoriented, and can potentially put their squad mates in danger of friendly fire.

The wedge is the fire team’s basic formation. It can expand and contract to take advantage of terrain. Limited visibility, however, can force the team to adopt other formations with are sub-optimal in that they provide less control, security, and flexibility.

The wedge is the fire team’s basic formation. It can expand and contract to take advantage of terrain. Limited visibility, however, can force the team to adopt other formations with are sub-optimal in that they provide less control, security, and flexibility.

We can learn to sense things in our environment quickly and naturally by aligning our perceptions to enhanced sensations.

NORTH

Researchers at University of Osnabrück in Germany developed a belt that holds vibrating motors. A control unit senses magnetic north and turns on and off the motors. The skin senses the vibration and the wearer’s brain learns to associate the vibration with direction imparting an intuitive sense of direction almost instantly.

NORTH

We can extrapolate this to three dimensions and potentially many targets.

RFID data broadcast by individual soldiers can be mapped onto our scalp using changes in vibration, electro-conductivity, or temperature.

Changes in X, Y position can be mapped to surface locations and relative distance can be encoded as stimuli strength (amplitude, frequency, or temperature).

Any relevant information gathered by RFID (or other types of sensors) can be mapped onto different sensational modalities.

http://www.atactech.com/PR_tactors.html

Vibrotactile actuation was chosen as a feedback mechanism for several reasons. Tactile actuators were chosen for their compact size, high output power density, resonant frequency of 250 Hz (for maximum detection by humans) and previous history of use. They allow the frequency to be controlled independently of amplitude, and allow very quick ring-up and ring-down times. The high bandwidth response is ideal for the quick feedback responses to fast-moving stimuli.