Motion Simulator - Different Types of Motion Platforms

Different Types of Motion Platforms

Motion platforms historically have spanned a broad spectrum in scale and cost. Those in the category of amusement park rides and commercial and military aircraft simulators are at the high end of this spectrum with arcade style amusement devices falling into the middle of the spectrum while smaller and lower-costing home based motion platforms comprising the other end.

While modern motion platforms have become complicated machines, motion platforms have much simpler roots. Many of the early motion platforms were flight simulators used to train pilots. One of the first motion platforms, the Sanders Teacher, was created in 1910. The Sanders Teacher was an aircraft with control surfaces fitted to the ground by a simple universal joint. When wind was present, the pilot in training was able to use the control surfaces to move the simulator in the three rotational degrees of freedom. Around 1930, a large advancement in motion platforms was made with the creation of the Link Trainer. The Link Trainer used the control stick and external motors to control organ bellows located under the simulator. The bellows could inflate or deflate, causing the simulator to rotate with three degrees of freedom. In 1958 the Comet IV was designed using a 3 degree of freedom hydraulic system. After the Comet IV both the range of motion and the degrees of freedom exhibited by motion platforms was increased. The most expensive motion platforms utilize high fidelity six degree of freedom motion, often coupled with advanced audio and visual systems. Today you will find motion platforms in many applications including: flight simulation, driving simulation, amusement rides, and even small home based motion platforms.

The high-end motion platform has been used in conjunction with military and commercial flight instruction and training applications. However, today you will find multiple occupant entertainment applications in theme parks throughout the world. The systems used in these applications are very large, weighing several tons typically housed in facilities designed expressly for them. As a result of the force required to move the weight of these larger simulator systems and one or more occupants, the motion platform must be controlled by powerful and expensive hydraulic or electromagnetic cylinders. The cost of this type of motion platform exceeds $100,000 US dollars, and often goes well into the millions for a multi-occupant system found at major theme park attractions. The complexity of these systems require an extensive amount of programming and maintenance, which further extends the cost associated with this type of motion platform.

The most typical high-end motion system that provides full 6 degrees of freedom (3 translation and 3 rotation) is the Stewart platform, which employs sophisticated algorithms to provide high fidelity motions and accelerations. These are used in a number of applications, including Flight simulators for training pilots. However, the complexity and expensive mechanisms required to incorporate all degrees of freedom has led to alternative motion simulation technology using mainly the three rotational degrees of freedom. An analysis of capabilities of these systems reveals that a simulator with three rotational degrees of freedom is capable of producing motion simulation quality and vestibular motion sensations comparable to that produced by a Stewart platform. Historically these systems used hydraulics or pneumatics, however many modern systems use electric actuators.

The middle of the spectrum includes a number of disclosures involving powered motion platforms aimed at arcade style amusement games, rides, and other arrangements. These systems fall into a price range from $10,000 to $99,000 USD. Typically the space requirements for such a platform are modest requiring only a portion of an arcade room and a smaller range of motion is provided via similar, less expensive, control systems than the high-end platforms.

The lower-cost systems include home-based motion platforms, which have recently become a more common device used to enhance video games, simulation, and virtual reality. These systems fall into a price range from $1,000 to $9,000 USD. Within the 2000s (decade), several individuals and business entities have developed these smaller, more affordable motion systems. Most of these systems were developed mainly by flight simulation enthusiasts, were sold as do it yourself projects, and could be assembled in the home from common components for around one thousand US dollars ($1,000). Recently, there has been increased market interest in motion platforms for more personal, in-home, use. The application of these motion systems extends beyond just flight training simulation into a larger market of more generalized "Craft-Oriented" simulation, entertainment, and virtual reality systems.