Walk simulation apparatus for exercise and virtual reality

This application is a continuation-in-part of co-pending U.S. patent application Ser. No. 10/853,886 filed May 26, 2004, which claimed the benefit of and priority from U.S. Provisional Patent Application Ser. No. 60/474,780 filed May 29, 2003, the benefit and priority of which is also claimed by the instant application.

The present invention relates in general to an exercise platform. In particular, the present invention relates to a walk simulation apparatus for exercise and virtual reality.

There is a growing demand for exercise machines to become more entertaining and less tedious. Similarly, users of virtual reality computer games wish to enhance their experience through physical stimulation and exertion, thereby increasing their “immersion” in the game. To this end many developments have sought to improve the computer gaming experience, for instance through three-dimensional visual graphics, ‘surround sound’ audio and various devices that provide a physical feedback.

As many games require the player to walk or run around a virtual world, several inventions have attempted to simulate walking and running. The key challenge to accomplishing this is to achieve a means of multi-directional movement within the restricted space usually required of such a game, while keeping the whole device compact.

A feature of walking/running exercise devices is that they tend to be computer controlled as opposed to providing an input to a computer. For instance, a treadmill requires the user to input the desired speed at which it should operate. There are dangers associated with forcing a user to ‘keep up’ with a machine, and the user may suffer comfort and modesty issues due to the jogging motion. Another feature of many existing devices is that it can be difficult or even impossible to change direction. Ideally a locomotion platform should allow a user to traverse freely in any horizontal direction for any amount of time.

Phillips\' U.S. Pat. No. 6,106,397 demonstrates that when a user is constrained to a limited platform area while performing a walking action her/her movements can be monitored and the data used as input to a computer program. However, the disclosed platform is flat.

The US Army has been very active in exploiting computer game technology for training and recruitment. Virtual reality mission rehearsal allows Military to research mission scenarios to evaluate impact of new equipment, combat techniques, tactics and procedures on mission effectiveness. America\'s Army is a First Person Shooter style computer game released free by the U.S. Army. It provides an indication of how seriously the U.S Army perceives game technology to be. The US Army has already installed ‘Omni-directional treadmills’ at the U.S Army Research Laboratory at Aberdeen Proving Ground, Md. and at Dismounted Battlespace Battle Lab Simulation Center at Fort Benning, Ga. However, their design is extremely cumbersome, requiring the user to wear a harness in case he/she falls onto the 3400 computer controlled rollers. Originally built in 1997, a purchase order was approved in 2004 to spend a further $2.9M on improvements. What is needed is a device that has no moving parts and overcomes many significant drawbacks of the above design that were identified in a report by the US Naval College at Monterrey.

There is a need for improved situation awareness training. A student can be forgiven for not knowing what is happening behind them if the student is training using a traditional keypad and screen, but that serious limitation is imposed by the equipment. Situation awareness training is a serious topic of research pertaining particularly to the military and aviation.

There is a need for improved Virtual Reality (VR) therapy. VR therapy provides controlled exposure to situations that patients find stressful. A broad range of conditions are treated including post traumatic stress disorder (PTSD), a variety of phobias and other anxiety syndromes.

There is a need for improved virtual tourism. Computer generated renditions of famous and historic places are becoming commonplace. They are generated using both computer graphics and by stitching together photographs taken from multiple angles. Now that such rich virtual environments are available, a basic human desire is to want to walk around them as any tourist would do if the tourist were actually at the real life version of the simulated environment.

Accordingly, there is a need for a simple concave platform for a user to stand on. There is a further need for a mechanism to reduce friction between a platform and a user. There is an additional need for a user to be constrained to the platform area but able to turn, jump, crouch, run and walk in any horizontal direction. The present invention satisfies these needs and provides other related advantages.

The objective of the disclosed invention is to provide a locomotion platform. The apparatus is a concave platform for a user to stand on. The platform and/or the user\'s footwear are manufactured in such a way as to reduce the friction between them. Further objectives are that the users remain constrained to the platform area and that they may turn and walk in any horizontal direction. The locomotion platform has been designed to encourage people to exercise as well as change the way that computer games are played. The concept is to allow a person to physically walk and run around within a first person computer game or training simulation. The present invention is simple, compact, contains no moving parts, and is easy to manufacture and maintain. The health benefits are significant. The age when many children spend a large amount of time playing games coincides with the 11 to 14 age group. This period is thought to influence a person\'s attitude to exercise throughout their life. Many parents are concerned about the amount of time their children spend sitting during their favorite pastimes. Brisk walking is now regarded as probably being the best form of exercise. A twenty minute walk, three times a week can provide much of the exercise people need. But no exercise device is beneficial unless it gets used. This health improving opportunity stems from providing frequent, weight-bearing, aerobic and cardiovascular exercise of sufficient duration, without it feeling like a chore. Considering that no one books a ski vacation just to get fit, exercise should be fun. The fact that the locomotion platform can be used in private will appeal to those in need of exercise but who are self-conscious about doing so in public.

The present invention makes the gaming experience much more immersive and thus far more entertaining. If greater immersion is attained, it will also make serious virtual reality training exercises more effective, and in the opinion of military leaders, fire-chiefs and many others, that saves lives. Computer game interfaces have not fundamentally changed since their inception. They require the player to view the action through a ‘window’ (screen) and control events by pressing keys. Many people think this to be a significant drawback as it prevents the player from feeling part of the action. The rapid growth of the computer games market has been driven more than anything else by achieving greater levels of immersion. The present invention recognizes that there is a limit to how immersive games can be when players remain ‘outside’ the game (i.e., looking in) rather than feeling they are ‘in’ the game.

Video glasses with head tracking have gone part of the way to overcoming this limitation but the locomotion aspect that the present invention provides has so far been missing.

Some people experience nausea when playing first and third person computer games. This may be due to the separation of perceived movement from actual movement (in a similar manner to travel sickness). The locomotion platform requires the user to physically turn around if they want to look behind them and should therefore be more natural.

In an exemplary embodiment of the present invention, a locomotion platform device permits a user to walk, run, crouch, jump or change direction, and continue these motions without impediment, while actually remaining constrained to the area of the device. A platform includes an upward facing, parabolic, concave surface upon which the user stands while performing the motions; and a mechanism for reducing friction of a portion of the user\'s footwear or feet contacting the surface of the platform sufficiently to allow omni-directional motion; wherein users do not move substantially away from a center of the platform as the user moves his/her feet.

In another exemplary embodiment of the present invention, a simulation system comprises a locomotion platform permitting a user to walk, run, crouch, jump or change direction, and continue these motions without impediment, while remaining constrained to the area of the device, where the platform includes an upward facing, parabolic, concave surface upon which the user stands while performing these motions. The system includes a mechanism for reducing friction of a portion of the user\'s footwear or feet contacting the surface of the platform sufficiently to allow omni-directional motion; wherein the user does not move substantially away from a center of the platform as the user moves his/her feet. A screen at least partially surrounds the platform wherein background images are projected onto the screen; and a camera is disposed between the screen and the platform.

Further features and advantages of the invention, as well as the structure and operation of various embodiments of the invention, are described in detail below with reference to the accompanying drawings.