The idea of virtual touch in computing is as foreign to most people as the concept of television was in the age of radio. But, like the innovation of TV, the Novint Falcon, powered by our patented 3D touch technology, represents an entirely new way to experience games. Touch is an integral part of how we experience things, both physically and emotionally. Until now, high-fidelity touch has been absent from computer interface. Like movies before the introduction of sound, today’s games are missing an important part of the sensory experience. So grab the Falcon and feel the next generation of gaming!

How the Novint Falcon Works

Users hold onto the Falcon’s interchangeable Grip (or handle) which moves left and right and forwards and backwards, like a computer mouse, but also moves up and down. The Grip can come in many shapes and forms and includes a quick disconnect feature which lets users change handles for specific uses or types of game play. As the Grip is moved, the computer keeps track of a 3D cursor. When the 3D cursor touches a virtual object, the computer registers contact with that object and updates currents to motors in the device to create an appropriate force to the device’s handle, which the user feels. The computer updates the position of the device, and updates the currents to the motors a thousand times a second (i.e. at a 1 kilohertz rate), providing a very realistic sense of touch. The three electrical motors are connected to the three arms extending out of the device, with one motor connected to each arm. The three arms are connected to the device’s handle. At any given cycle, or 1/1000th of a second, the device can create a force on the handle in any direction of any magnitude, up to the maximum force.

For example, when a 3D cursor touches a virtual sphere, there is a force normal (perpendicular) to the surface. The device reacts and pushes in the radial direction away from the center of the sphere, proportional to how hard the user pushes against the sphere. The computer keeps track of the direction of the force (based on the position of the cursor) and the amount of the force, 1000 times a second which lets the user slide the 3D cursor across the surface of the sphere, giving it a consistent smooth feel. The effect is that the cursor, and therefore device, physically cannot move through the sphere, and it is actually a virtual solid object. When one looks at the Novint Falcon itself (rather than the cursor and sphere graphics on the computer screen), one can see the “invisible” sphere in the haptic workspace where the haptic device cannot move – it is really there, and you can really touch it! Additionally, other forces and algorithms can be used to give the sphere texture, dynamic properties (i.e. it can bounce like a ball), deformability, or a variety of other effects.

What is Haptics

Haptics (pronounced HAP-tiks) is the scientific field that studies the sense of touch. In computing, Haptics is the science and art of applying touch sensation to human interaction with computers. A haptic device gives people a sense of touch with computer generated environments, so that when virtual objects are touched, they seem real and tangible. An example is a medical training simulator in which a doctor can feel a scalpel cut through virtual skin, feel a needle push through virtual tissue, or feel a drill drilling through virtual bone. All of these types of interactions can feel almost indistinguishable from the real life interactions the simulator emulates. Haptics is applicable across nearly all areas of computing including video games, medical training, scientific visualization, CAD/CAM, computer animation, engineering design and analysis, architectural layout, virtual toys, remote vehicle and robot control, automotive design, art, medical rehabilitation, and interfaces for the blind, to name a few. The word 'haptics' derives from the Greek haptikos, from haptesthai, meaning “to grasp, touch, or perceive”, equiv. to hap(tein) to grasp, sense, perceive.

In computing, haptics is implemented through different types of interactions with a haptic device communicating with a computer. These interactions can be categorized into the different types of touch sensations a user can receive -- force feedback, tactile feedback, and proprioception (or kinesthesia).

With force feedback, a user can feel forces applied to a user’s body by the movements of a haptic device, sensed by the user primarily through musculoskeletal forces, but also through the skin that touches the physical interface to a haptic device. This is often accomplished through a user’s hand grasping a handle connected within the device to motors (e.g. 3D haptic devices, like the Novint Falcon, and 2D haptic devices like force feedback steering wheels and force feedback joysticks), but can also be implemented with haptic devices that a user puts a hand, arm, or leg into (e.g. a haptic glove or sleeve); vibrating motors within something that is held (e.g. a game controller or a force feedback mouse); a vibrating or moving object that a user sits on; or any other mechanical system that can give forces or touch sensations to a user. Haptics is often accomplished through electrical motors, although there are other methods to create force sensations such as with devices that are pneumatic (air controlled), hydraulic (fluid controlled), piezoelectric (materials that expand or contract with electric current), electric (sending currents directly to a users skin or nervous system), or which use passive braking systems.

With tactile feedback, a user can feel forces applied directly to the skin, which are detected by a user through sensors within the skin called mechanoreceptors. Tactile feedback can also be applied to a user through electrical currents applied directly to the skin or objects that can vary in temperature touching the skin. For example, tactile feedback can be accomplished with pin arrays on a haptic device that a user places a hand or finger on. The pins within the pin array can slightly raise or lower as the haptic device moves, giving a sensation that the user’s finger or hand is moving across a virtual object with texture.

Proprioception is the sense of where one’s body is in space. For example, if you move your arm out to the side, even if your eyes are closed, you know where it is. Our sense of proprioception is derived from the forces our muscles exert within our body. Force feedback generally has a proprioceptive component, as a user’s movements of a haptic device in correlation with an application create the forces one feels. Even computer input devices that are generally not considered haptic devices use our sense of proprioception, such as mice and keyboards. Kinesthesia is similar to proprioception, in that it is a sensation of strain in muscles, and through it we know our body position, but kinesthesia also includes other internal feelings such as the feeling of a full stomach.

Haptic devices have varying complexities, and can move in different ways. Force feedback devices are often described by their Degrees of Freedom (DOF). A Degree of Freedom refers to a direction of movement. Common Degrees of Freedom include right-left movement (X), up-down movement (Y), forwards-backwards movement (Z), roll (rotation about the Z axis), pitch (rotation about the X axis), and yaw (rotation about the Y axis). Degrees of Freedom can refer both to how a device keeps track of position, and how a device outputs forces. A mouse, for example, is a 2 DOF input device – it keeps track of position in the right-left Degree of Freedom, and the forward-backward Degree of Freedom. A joystick is also a 2 DOF device, but its Degrees of Freedom are different (it rotates forwards-backward, and right-left). A force feedback joystick is a 2 DOF device with force feedback. It both tracks 2 DOF and gives simple forces in 2 DOF. The Novint Falcon is a 3 DOF force feedback device. It tracks in 3 DOF (right-left, forwards-backwards, and up-down), and gives forces in those same Degrees of Freedom. 3 DOF devices (and higher DOF devices) are significantly more complex than 2 DOF devices.

Novint develops 3D haptic technology and products that enable people to experience a realistic sense of touch using their computer. Using our 3D haptic interface device, the Novint Falcon, and patented 3D haptic software, computer users may feel 3D objects, feel their shapes and textures, feel the dynamic properties of objects, and feel many other effects. The Novint Falcon gives force feedback through interchangeable handles that a user holds on to. Forces are created through the use of 3 electrical motors, 1 motor connected to each of the 3 arms in the device. The 3 arms connect to the device’s handle. The Novint Falcon is, essentially, a small robot, yet its industrial design is something that consumers will enjoy having on their desktop. Although it gives extremely complex 3D haptic interactions, it is beautiful in its fundamental simplicity and elegance.

Although haptic devices have been available for commercial applications for many years, these devices have historically cost tens of thousands to hundreds of thousands of dollars. The Novint Falcon, which is designed as an affordable consumer controller, represents a significant advancement in the field of haptics, making high-fidelity 3D touch accessible to the consumer market for the first time.