Haptics Transmission Systems

• US 20080231594A1
• Filed: 09/22/2004
• Published: 09/25/2008
• Est. Priority Date: 09/25/2003
• Status: Active Grant

• Current Assignee: British Telecommunications PLC (BT Group PLC)
• Original Assignee: British Telecommunications PLC (BT Group PLC)
• Inventors: Hardwick, Andrew J., Furner, Stephen M.
• Granted Patent: US 7,746,320 B2
• Time in Patent Office: Days
• US Class Current: 345/156
• CPC Class Codes: A63F 13/12 involving interaction between a plurality of game devices, e.g. transmisison or distribution systems protocols for networked virtual reality, networked games H04L29/06034
• CPC Class Codes: A63F 13/285 Generating tactile feedback signals via the game input device, e.g. force feedback
• CPC Class Codes: A63F 13/30 Interconnection arrangements between game servers and game devices; Interconnection arrangements between game devices; Interconnection arrangements between game servers
• CPC Class Codes: A63F 13/335 using Internet
• CPC Class Codes: A63F 13/358 Adapting the game course according to the network or server load, e.g. for reducing latency due to different connection speeds between clients
• CPC Class Codes: A63F 2300/1037 being specially adapted for converting control signals received from the game device into a haptic signal, e.g. using force feedback
• CPC Class Codes: A63F 2300/534 for network load management, e.g. bandwidth optimization, latency reduction
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user

Abstract

A method of compensating for network latency in haptics transmission in which the position of a haptic effector is controlled by signals received from a network. The method comprises storing a series of locations of the haptic effector, determining from the series using Fourier Transformation or other means frequencies having a growing amplitude and creating a filter function to eliminate the growing frequencies from output signals directing the force and direction of the haptic effector.

Claims

1. A method of activating a haptic output device of the kind responsive to signals defining directional force comprising receiving a series of signals defining a multiplicity of data packets, each packet defining a directional force applied at one location for transmission to the current location, determining from packet data the information defining a position to which a haptic output device is expected to move, using current positional data to generate output signals defining force and direction, applying a damping factor to said force and direction signals to slow the rate of movement from a previously defined position towards the current defined position, storing data defining each of a multiplicity of positions to which the haptic output device has moved, analysing said data to determine frequency components in the movement which are increasing, creating a filter function to remove said growing frequency components and applying said filter function to said force and direction signals to eliminate said frequency components from movement effected by the haptic output device.

2. The method of claim 1 further including signaling in each direction whereby haptic forces applied at one device in reaction to an applied force towards the current defined position are reflected to a corresponding device in the form of current positional signals in a series of return data packets.

3. The method of claim 1 further including calculating the filter function from determined parameters of a transmission network on which said data packets are carried.

4. The method of claim 3 in which latency of the network is determined by transmitting a data packet to the network said packet including a time determinant identity, reflecting the data packet through the network and comparing the received time with the transmitted time to provide a latency parameter from which said filtering factor is determined.

5. The method of claim 4 in which at least some transmitted packets carrying positional data also include the time determinant data, some of said time determinant data being returned to permit updating of the latency parameter.

6. The method of claim 1 further including applying a modifying factor to the force and direction signals, said modifying factor being derived from predetermined user preference data.

7. An interactive haptic output terminal in combination with a bi-directional transmission arrangement, the terminal comprising at least a haptic output device and control means, said control means receiving signals from said haptic output device to determine a current position for said device, and to determine from signals received from said transmission arrangement a preferred current position for said haptic output device, said control mean determining an output force and direction required to move said haptic output device from the current position to the preferred position, modifying said output force and direction by storing data defining each of a multiplicity of positions to which the haptic output device has moved, analysing said data to determine frequency components in the movement which are increasing, creating a filter function to remove said growing frequency components and applying said filter function to said force and direction signals to eliminate said frequency components from movement effected by the haptic output device.

8. A terminal as claimed in claim 7 in which the control means receives signals from the haptic output device, said signals containing data defining the position of said device at any particular time, said control means converting said data to signals for transmission to said bi-directional transmission arrangement at predetermined intervals.

9. A terminal as claimed in claim 7 in which the signals defining a preferred current position are generated by an environment simulator, for example a programmed computer.

10. A terminal as claimed in claim 7 in which the signals defining a preferred current position are generated by a corresponding interactive output terminal at the opposed end of the transmission arrangement.