Patent Application
20140265113
Amusement game devices, such as pinball machines, video games, redemption games, etc. of the commercial, e.g., revenue generating, and non-commercial, e.g., home entertainment, type are well known in the art. By way of example, U.S. Pat. No. 5,338,031, U.S. Pat. No. 6,158,737, and U.S. Published Application No. 2007/0026918 (which publications are incorporated herein by reference in their entirety) illustrate and describe amusement game devices of the type having a cabinet which houses a playfield assembly including a playing field or playfield which may be inclined. As further described in the '031 patent, it is known that players often attempt to lift, shake, shove, tilt, etc. such amusement game devices (individually and collectively referred to herein as “tilting” an amusement game device) for the purpose of influencing operation of the devices to their advantage. Thus, in order to prevent such abuse, amusement game device manufacturers have developed tilt prevention mechanisms that terminate play of the game, in whole or in part, if the amusement game device is tilted beyond predetermined limits. Conventionally utilized tilt prevention mechanisms include an electrically conductive member suspended from the game cabinet in pendulum fashion and an electrical contact surrounding the conductive member. When the game is tilted during game play the free end of the conductive member swings into the contact ring and completes a circuit directing the game's microprocessor to stop play as described above.
The following describes an improved tilt sensing system and method for an amusement game device, such as a pinball machine. Generally, operation of an amusement game device is controlled in part by using an accelerometer positioned with a game cabinet of the amusement game device. The accelerometer is first used to establish a reference idle position for the amusement game device. During game play of the amusement game device, it is then determined if a force applied to the amusement game device as sensed by the accelerometer exceeds a threshold that is set relative to the reference idle position for the amusement game device. When it is determined that a force applied to the amusement game device as sensed by the accelerometer during play of the amusement game device exceeds the threshold that is set relative to the reference idle position for the amusement game device, play of the amusement game device is caused to be inhibited in whole or in part.
A better understanding of the objects, advantages, features, properties and relationships of the tilt sensing mechanism for an amusement game device described hereinafter will be obtained from the following detailed description and accompanying drawings which set forth illustrative embodiments which are indicative of the various ways in which the principles of the invention may be employed.
For a better understanding of the amusement game device described hereinafter reference may be had to the following drawings in which:
With reference to the Figures, an amusement game device, in the exemplary form of a pinball machine 10 is now described. It is to be appreciated, however, that this exemplary form for the amusement game device 10 is not intended to be limiting. Rather, those of ordinary skill in the art will appreciated that the tilt sensing mechanism described hereinafter can be utilized in any type of amusement game device, such as video games, redemption games, etc. of the commercial and non-commercial type, in which it is desired to inhibit a user's tilting of the amusement game device during play thereof.
In keeping with the example of an amusement game device 10 of the pinball machine type, the amusement game device 10 illustrated in
For sensing a tilting of the amusement game device 10, the amusement game device 10 is provided with an accelerometer 40. As shown in
In an exemplary embodiment, a microelectromechanical system (MEMS) device is utilized as the accelerometer 40. As will be understood, a MEMS device is a very small mechanical device with an electronic interface. As will be further understood, a MEMS accelerometer device comprises a reference mass on a cantilever beam. Flexing of the beam in response to a tilting of the amusement game device 10 is measured by the MEMS accelerometer device and a signal indicative of the measured tilting is provided to the processing device 42 for processing in accordance with the appropriate instructions as stored on memory device 48. As described below, the signal indicative of the measured tilting of the amusement game device can be in the form of an interrupt signal that is generated when a measured tilting force applied to the amusement device 10 exceeds a predetermined threshold.
As will be appreciated, the use of an accelerometer 40 to detect tilting of the amusement device 10, e.g., to sense both inclination and impact, has many benefits when compared to the aforementioned plumb tilt mechanism that is conventionally utilized in amusement games. For example, a MEMS accelerometer device is much less costly when considered against the cost of the components required to construct a plumb tilt mechanism. A MEMS accelerometer device is also easier to setup and adjust when compared to a plumb tilt mechanism, e.g., with a MEMS accelerometer device no mechanical components need to be arranged and sensitivity can be adjusted in software rather than by physically adjusting the plumb bob relative to the conductive ring. Yet further, a MEMS accelerometer device provides a more consistent response when compared to a plumb tilt mechanism, e.g., because the devices can be adjusted in software multiple devices can be set to provide near identical responses (which is particularly useful for tournament play) whereas the mechanical plumb tilt mechanism has more room for adjustment/calibration errors. Still further, a MEMS accelerometer device can be auto-calibrated via use of software, e.g., the software can be used to determine which direction is straight down and using this information can provide for compensation even if the board carrying the MEMS accelerometer device is installed on an angle. In addition, a MEMS accelerometer device can be used to measure applied forces in any direction not just horizontally.
While accelerometers can be found with one, two or three axes of measurement, in a preferred embodiment a three-axis (x, y, and z) MEMS accelerometer is utilized as the three-axis accelerometer provides, in keeping with the advantages above-noted, easy auto-calibration and the ability to detect motion in any direction.
In keeping with this preferred embodiment, before the MEMS accelerometer device is used to sense tilting of the amusement game device 10 during operation of the amusement game device 10, a small amount of configuration is generally required to set operational parameters, such as the range of sensitivity. In this regard, the accelerometer 40 may be configured to generate an interrupt signal (for provision to the processing device 42) when a specified tilting threshold is exceeded, such as when the amusement game device receives an impact, is in sensed free-fall, etc. As will be understood, providing a signal in the form of an interrupt helps to reduce the amount of communication necessary with the processing device 42. While it is preferred that the accelerometer 40 perform such threshold evaluations (which would require that the accelerometer 40 be a component part of an integrated circuit having a processing device, be placed on a board carrying a processing device, etc.), it is contemplated that such threshold evaluations could be performed by the processing device 42 using signals having data indicative of any forces applied to the amusement game device as provided to the processing device 42 by the accelerometer 40.
To calibrate the amusement game device 10, the amusement game device 10 is placed into idle, i.e., a state in which the amusement game device 10 is at rest with no external forces acting upon the amusement game device 10 other than gravity. In this state, an acceleration of approximately 1 g straight down is measured by the accelerometer 40 due to gravity. The three axes of the amusement game device 10 can then be referenced to this measured reference (idle) position (the reference position being in effect the position of the plumb bob hanging at rest centered within the contact ring). As this calibration is to be done when the amusement game device 10 is idled, it is preferred that the calibration be operator controlled, i.e., that it be initiated via use of a secure menuing system (e.g., a menuing system which is accessed by unlocking and opening the amusement game machine) such as described in U.S. Pat. No. 7,967,681 which patent is incorporated herein by reference in its entirety.
Once the idle position is referenced in the amusement game device 10, it will be appreciated that the system can be used to determine if, for example, the amusement game device 10 is shoved horizontally. In this regard, any force horizontally applied to the amusement game device 10 can be measured as an acceleration in a plane which is roughly perpendicular to what was calibrated as straight down. In a first embodiment, an acceleration threshold would be set in this plane and any acceleration that exceeds the threshold would be treated as a tilt event and an interrupt signal would be generated as noted above. Preferably, the threshold can be operator adjusted in software via the secure menuing system, e.g., via a selection of a desired numeric threshold on a pre-defined sensitivity scale or range, which setup is simpler and more repeatable across plural machines as compared to adjusting the height of a mechanical plumb bob.
In a second embodiment, an algorithm could be employed to emulate the behavior of the plumb bob. This may help to maintain the feel of the mechanical tilt mechanism. A “virtual plumb bob” could be implemented as a pendulum in two axes. Forces in the plane perpendicular to straight down would add energy to or subtract energy from the accelerometer pendulum, depending on the direction of movement of the pendulum and the direction of the incident force. If the position of the “virtual plumb bob” exceeds a predetermined radius a tilt event is sensed and a corresponding interrupt signal can be sent to the processing device 42.
It will be additionally appreciated that beyond simply measuring force in the plane parallel to the ground a 3-axis accelerometer can accurately detect more subtle changes such as if the amusement game device is lifted off the ground. For example, if a game is being operated as part of a tournament the accelerometer device may be able to detect, e.g., by detecting a repositioning force being applied to the machine whereupon the repositioning of the machine remains unchanged over time, that someone applied a shim or otherwise raised the front legs of the amusement game device 10 to slow down the play of the amusement game device 10. In this manner the accelerometer 40 can serve as a deterrent to cheating in a tournament.
While a specific embodiment of the invention has been described in detail, it will be appreciated by those skilled in the art that various modifications and alternatives to those details could be developed in light of the overall teachings of the disclosure. Accordingly, the particular arrangement disclosed is meant to be illustrative only and not limiting as to the scope of the invention which is to be given the full breadth of the appended claims and any equivalents thereof.
