Patent Grant
7803031
The present invention relates to vehicles and apparatus that move along the ground or a support surface without directly powered wheels, and more particularly relates to a vehicle that propels itself along a support surface by a moving weight or force.
Many efforts are known to produce a vehicle that travels along a support surface such as the ground without applying a rotational force upon wheels of the vehicle in contact with the ground. Such vehicles are sought for a variety of purposes, including the simple novelty, or toy-like entertainment value of an innovative or unusual vehicle, as well as a desire for possibly robotic vehicles to travel over uneven terrain that circular wheels cannot ordinarily traverse, for such things as remote exploration or land mine detecting, as well as for micro machines that cannot be manufactured with the usual complexity of their macroscopic counterparts, etc. For example, a gyrostat propulsion system is disclosed in U.S. Pat. No. 5,090,260 to Delroy, and includes rotational spin of two gyrostats secured within a frame to produce precessional forces upon the frame to thereby move the frame. Delroy, however, is extraordinarily complex, and therefore too costly to achieve any valuable function.
Additional attempts to directly convert the traditional rotational force of motors to linear motion are shown in U.S. Pat. No. 4,884,465 to Zachystal which uses a spinning weight that rotates within a frame that supports opposed, extending legs. Similarly, a “walking vehicle” is shown in U.S. Pat. No. 4,662,465 to Stewart, wherein use of rotation between two separate, but linked bodies is utilized with alternate lifting of the bodies through overlapping pairs of flexible legs that support the approximately co-axial bodies in order to move the vehicle over uneven terrain. A much older effort is disclosed in U.S. Pat. No. 2,886,976 to Dean, that shows use of opposed, eccentric rotating weights to generate a controlled linear motion. More recently, U.S. Pat. No. 4,834,200 to Kajita shows use of shifting a center of gravity to produce movement of a pair of legs that support an erect body, much like a human-like robot, in an effort to move the robot over steps, and similar uneven terrain.
All of these and other known efforts to produce a vehicle that propels itself without a rotational force applied directly to circular wheels, or directly to drive wheels such as in tracked vehicles, involve extraordinarily complex apparatus that would be very costly to manufacture. Perhaps more importantly, known efforts have not been successful at engaging rough terrain and have not produced an efficient use of the rotational force, compared to traditional, circular wheeled vehicles. Accordingly, there is a need for a vehicle that can propel itself by way of an efficient use of force that is not mechanically linked to rotation of circular wheels supporting and moving the vehicle.
The invention is a vehicle having non-circular wheels propelled by a moving weight or force. Essentially, the vehicle includes a frame having three or more non-circular wheels at a periphery of the vehicle, wherein the wheels are mechanically secured to each other so that whenever one non-circular wheel moves, the other wheels move. An offset arm powered by a motor moves a weight around a weight circumference defined around an approximate geometric center between the non-circular wheels to sequentially tip them so that their sequential tipping moves the vehicle in a direction of travel of the vehicle.
More specifically, the vehicle includes a frame having a first axle and a second axle secured to the frame and having a linkage such as a chain or belt secured between the two axles for rotating the first axle upon rotation of the second axle and for rotation of the second axle upon rotation of the first axle. A first non-circular wheel and a second non-circular wheel are firmly secured to opposed ends of the first axle, and at least a third non-circular wheel is firmly secured to the second axle, and typically a fourth non-circular wheel is secured to an opposed end of the second axle. Each non-circular wheel includes a perimeter having at least three contact segments for contacting a support surface under and supporting the vehicle. In some embodiments, the non-circular wheels may have two contact segments, such as a high aspect ratio rectangle. By the phrase “firmly secured”, it is meant that rotation of one non-circular wheel, such as the first, causes rotation of the second non-circular wheel, and through the linkage, also causes rotation of the second axle and its firmly secured third and any fourth non-circular wheels.
The non-circular wheels are secured to the axles in a specific sequential alignment. The sequential alignment means that whenever a first contact segment of the first non-circular wheel is secured to the first axle in a contact alignment to contact the support surface below the vehicle, a first contact segment of the second non-circular wheel is secured to the opposed end of the first axle in a collapse alignment. By “collapse alignment”, it is meant that motion of the vehicle in a direction of travel will move the second non-circular wheel from the collapse alignment immediately into the contact alignment. Additionally, whenever the first contact segment of the second non-circular wheel is in a contact alignment, a first contact segment of the third non-circular wheel is secured to the second axle in the collapse alignment. If the vehicle includes four non-circular wheels, then whenever the first contact segment of the third wheel is aligned in a contact alignment, the first contact segment of the fourth non-circular wheel would be aligned in a collapse alignment. The sequential alignment of the non-circular wheels includes the described sequence of all of the wheels being in either a clockwise or a counter clockwise orientation.
An offset arm is movably secured to a motor that is secured to the frame for moving the offset arm. The offset arm includes a weight support end and an opposed motor attachment end. The motor attachment end is movably secured to the motor for moving the arm such as by a rotational motion. The offset arm is dimensioned so that movement of the motor attachment end by the motor moves the weight support end about a weight-circumference defined by movement of the weight support end. The weight-circumference circles around an approximate geometric center between the non-circular wheels. A weight is supported by the weight support end of the offset arm, and the weight is sufficiently heavy and the weight support end of the offset arm is a sufficient distance from the geometric center between the wheels so that as the motor moves the weight support end of the arm along the weight-circumference through the sequential alignment of the non-circular wheels, gravity forces a non-circular wheel in the collapse alignment under the weight to collapse to the contact alignment. The axle or the linkage means then moves the next sequential non-circular wheel to the collapse alignment to be collapsed to the contact alignment as the weight moves through the weight-circumference. Therefore, the motion, such as a rotational motion of the offset arm, effectively causes the non-circular wheels to sequentially rotate from the collapse to the contact alignment, and then to another alignment, then back to the collapse alignment and again to the contact alignment. This sequential movement of the non-circular wheels thereby moves the vehicle in the direction of travel. The heavier the weight, the shorter the offset arm may be to achieve the described, sequential movement of the non-circular wheels, within reasonable limits of weight and length that may be readily measured by one skilled in the art.
In a preferred embodiment, the vehicle includes four non-circular wheels, and each non-circular wheel defines four sides, such as a square. In such an embodiment, whenever a first segment of the non-circular wheel is in the collapse alignment, an angle between the first segment and the contact surface would be approximately 22.5 degrees (“22.5°”). Alternatively, the four non-circular wheels may define three sides, such as an equilateral triangle, the angle between a first segment of such a wheel in the collapse alignment and the support surface would be about 30°. Additionally, the non-circular wheels may define five, six or more sides, wherein the more sides, the smoother the movement of the vehicle, but the closer a non-circular wheel is to defining a circular shape about the axle, the greater a loss of propelling potential.
In a further preferred embodiment, each non-circular wheel on the vehicle defines the same number of segments, and each wheel also defines the same angle between segments of each wheel. Because the angle between the segments is the same, the vehicle may readily travel in a forward or rearward direction of travel based upon whether the offset arm is moving in a clockwise or a counter clockwise direction.
Because the non-circular wheels are firmly secured through mechanical linkage and/or the axles, in certain embodiments steering the vehicle requires a non-traditional steering mechanism. In other embodiments, conventional steering may be utilized, especially where the vehicle is moving slowly and one of the non-circular wheels tends to lift as the wheels turn, minimizing any problems with a wheel dragging while turning with a conventional steering mechanism. In a certain embodiment, the vehicle may be steered by articulation of the frame about a center or pivot point. In another embodiment, steering may be achieved by having wheels on one side be or become greater in size. Additionally, steering may be achieved by a rotating plate that descends at predetermined intervals to the support surface to lift and rotate the frame to a desired orientation. Additionally, if the wheels were rotated about a vertical axis (like a conventional steering mechanism), and aligned so that they all tended to move around a circle, the car would rotate or turn about a vertical axis as the weight (force) was moved, thus changing the direction of the car. In such circumstances, whether the sequential alignment of the non-circular wheels is oriented to be clockwise or counter clockwise would determine whether the vehicle would turn in the same direction as the rotation of the force (or weight) or counter to that direction.
In yet another embodiment, the non-circular wheels may be in the form of spokes without a rim or may be in the form of star-shaped rods having no material between non-central end-points of the rods, wherein the end-points of the rods define vertices on a perimeter of a polygon. This would further facilitate movement over uneven terrain. The end-points may also be covered with support pads or they may form rounded tips, and the tips may also be of resilient material to further cushion movement of the vehicle.
The non-circular wheels discussed so far are generally polygons, having straight line segments joined about the wheel perimeter, where a contact angle of sequential line segments changes abruptly from one segment to the next segment. The non-circular wheels thus have discrete (discontinuous) changes in contact angles around the perimeter, from segment to segment. Just as The Calculus moves from the Riemann Sum to the definite integral (rough discontinuous functions to smooth continuous functions), so the contact angle of the non-circular wheel perimeter can change continuously, without discontinuity around the perimeter. Such non-circular wheel shapes therefore also include: non-circular wheels having smooth perimeters, such as an elliptical shape, or a round or circular perimeter with an axle of the wheel offset from a center of a circle, as discussed below; smooth contours connected at sharp points, such as a bi-convex wheel; straight segments connected at curved points, such as a square with round corners; combinations of smooth and abrupt contact angles; and, combinations thereof.
An exemplary and valuable embodiment of a different type of non-circular shape includes a vehicle that may be in the form of a vehicle having what is referred to herein as non-circular rotational perimeter wheels propelled by a moving weight or force. In this embodiment, the same principles described above utilize gravity of the rotating weight or other forces described herein to propel the vehicle along a direction of travel, using the described mechanical linkage of the wheels to each other (such as through the axles), the sequential alignment of the wheels, and the offset arm rotating a weight about the weight-circumference. However, each non-circular rotational perimeter wheel of this embodiment is secured to the axle in an essentially eccentric manner so that a point on the perimeter of a non-circular rotational wheel is a first distance from the axle, and an adjacent point is a distance from the axle that is different than the first distance.
Additionally, each non-circular rotational perimeter wheel includes a first contact segment that may consist of between about fifteen degrees and about forty-five degrees of the perimeter of the wheel (wherein each perimeter consists of three-hundred and sixty degrees about the axle) that is closest to the axle, and a second contact segment adjacent to the first contact segment, the second contact segment consisting of about at least fifteen degrees of the perimeter next to the first contact segment. The sequential alignment of the non-circular rotational perimeter wheel embodiment is the same as described above for the other embodiments. In other words, whenever a first contact segment of a first non-circular rotational perimeter wheel is secured to the first axle in the above described contact alignment to contact the support surface below the vehicle, a first contact segment of a second non-circular rotational perimeter wheel is secured to the opposed end of the first axle in a collapse alignment. Additionally, whenever the first contact segment of the second non-circular rotational perimeter wheel is in a contact alignment, a first contact segment of a third non-circular rotational perimeter wheel is secured to the second axle in the collapse alignment. As the vehicle of this embodiment proceeds along the direction of travel, like the other embodiments, the resulting vehicle motion produces a wobble-like effect because the perimeters of the wheels define non-circular rotation. The perimeters of the non-circular rotational perimeter wheels may be round, oval, egg-shaped, etc., provided they conform to the definitions above.
The invention also includes a method of propelling a vehicle, including the steps of securing three or more non-circular wheels or non-circular rotational perimeter wheels to a periphery of a frame of the vehicle, wherein the wheels are secured in the described alignment so that whenever a contact segment of the first non-circular wheel is in the contact alignment, a first contact segment of a second non-circular wheel is secured in the collapse alignment, then rotating an offset arm secured to a motor on the frame so that a weight supported by a weight end of the arm defines a weight-circumference around a geometric center between the wheels to sequentially tip the wheels from collapse alignments to contact alignments, thereby moving the vehicle in a direction of travel.
Accordingly, it is a general purpose of the present invention to provide a vehicle having non-circular wheels propelled by a moving weight that overcomes deficiencies of the prior art.
It is a more specific purpose to provide a vehicle having non-circular wheels propelled by a moving weight that readily moves over uneven terrain and that also minimizes manufacturing and operating costs of the vehicle.
These and other purposes and advantages of the present vehicle having non-circular wheels propelled by a moving weight will become more readily apparent when the following description is read in conjunction with the accompanying drawing.
Referring to the drawings in detail, a vehicle having non-circular wheels is shown in
A first non-circular wheel 20 and a second non-circular wheel 22 are firmly secured to opposed ends of the first axle 14, and a third non-circular wheel 24 and a fourth non-circular wheel 26 are firmly secured to opposed ends of the second axle 16. As best shown in
The non-circular wheels 20, 22, 24, 26 are secured to the frame 12 in a specific, sequential alignment. In
In
The moving force of the gravity of the weight 84 must create a moment on at least one of the non-circular wheels in the sequential alignment that thereby tends to drive the vehicle 10 in a rectilinear motion. The maximum magnitude of the necessary moment decreases as the number of sides increases, wherein a limit is that the wheel may not be a circular wheel so that such a wheel would be circular relative to rotation about the axle 14, 16.
Returning to
As with the
As the vehicle 100 of this
In a particular preferred embodiment as shown in
Steering apparatus to support the vehicle 10 as it moves along the direction of travel 30 have been discussed in general terms above, and also include all known steering means known in the art, including conventional steering mechanisms, that could be utilized with the firmly attached, non-circular wheels. It is pointed out, that in embodiments of the vehicle having non-circular wheels wherein the angles between segments of the wheels are all the same angle, the vehicle may readily move in a forward direction of travel 80, or in a rearward direction of travel if the rotation of the offset arm is reversed from the clockwise direction to a counter clockwise direction (not shown). Such forward then rearward motion may be part of a steering mechanism, wherein two fixed arcs, or two alternate steering directions are integrated into the relationship between the wheels, so that the vehicle 10 may travel in a forward direction on one arc for a predetermined distance and for a predetermined portion of an arc. Then the vehicle 10 is configured, such as by pivoting of a front end of the vehicle 10 relative to a back end of the vehicle 10. Then the rotation of the off set arm 76 is reversed, and the vehicle then progresses toward a predetermined destination along the second arc.
The driving force described is produced by gravity or a gravitational force, through the use of the weight 84, 84′ on the end of offset arm 76, 76′ which produces a normal force off-set from the geometric center of the non-circular wheels. The
For example, aerodynamic forces can be used to create advantageous forces on a vehicle without greatly increasing the mass (inertia) of the vehicle. “Formula I” race cars use airfoils to push the car down, thus increasing wheel friction and resistance to sliding, without increasing the inertia of the vehicle. This allows them to go around corners much faster than would otherwise be possible. In a similar way, the present vehicle 10, 100 could use aerodynamic forces to provide the off-set normal force to propel the vehicle 10 without increasing the inertia of the vehicle 10. An airfoil (or hydrofoil) could be employed in place of the off-set weight, and linked so that it always faced the flow source. An example of an electromagnetic embodiment could use an electro-magnet located near each wheel, which can pull down towards a steel (ferrous) riding surface. Each electro-magnet could be sequenced so as to provide the moving off-set force to propel the vehicle. Such magnets could be digitally sequenced, activating the next magnet in the sequence as (or just after) the current active magnet is deactivated. Alternatively, the power to the magnets could be smoothly varied so as to produce the effect of a normal force moving smoothly around a circular path, much like the weight. For extremely small versions of the present vehicle 10, 100 a moving magnetic force could be generated by a microelectronic circuit interacting with the vehicle. It seems that electro-magnetic and electro-static forces increase their effectiveness as the size of an object decreases, thus making the potential to propel objects much greater as the size decreases, which is a good case for micro-machines. Electrostatics could be used to create the off-set force using positively and negatively charged components.
While all the aforementioned embodiments 10, 100 use a moving force means that is not connected directly to the axles/wheels to facilitate the movement of the car, there are advantages to the sequential alignment, phase-locked nature of these embodiments in and of itself, such as in alternate embodiments (not shown) where the axles/wheels are directly driven by a motor/transmission of some sort. For example, a standard car with four square wheels would be very difficult to propel because at one time or another all the wheels would be in collapsed alignment at the same time, greatly lowering the center of gravity, and requiring all the wheels to lift the car at the same time. And, the ride would be very rough to say the least. This would not happen with the sequential alignment, phased-locked version, with 4 square wheels sequentially phased by 22.5 degrees for example, because the center of gravity remains much higher, and the wheels are never in collapsed alignment at the same time, consequently the ride is much smoother and the car much easier to propel. It is surprisingly easy to push the four square, non-circular wheel prototypes. This same embodiment with the four spoke wheel defining the corners of a square, non-circular wheel should have advantages over the conventional round wheel version traversing rough terrain. Embodiments with other number of wheels would also have this advantage. Consequently, this invention also includes the described embodiments having sequential alignment, phase-locked non-circular wheels propelled by a force acting upon the wheels in any manner known in the art, such as acting directly upon the wheels or upon the linkage between the wheels.
Research has been done upon actual embodiments 10, 100 and upon computer models of the present invention, and the research results are very encouraging. A mechanical locomotive device was modeled using an “AUTOLEV” brand name computer program. With an “ANIMAKEK” brand name software tool, visualization of the resulting motion was displayed. The model was created with twenty parameters of which six were critical to the design variation process. Each of these six parameters was varied independently so as to understand the relative robustness of the current design. The operating range of these parameters was determined. The working prototype's specific value of these six critical parameters was interestingly found in the middle third of the good operating range, meaning that the working prototype 10 shown in
To best understand the operational steps of the vehicle 10, each distinct step of a complete cycle of the offset weight rotation through a weight circumference about all of the wheels 20, 22, 24, 26 was determined. Gait is a term often used to understand the walking sequence of a human, a horse, or even a six legged robotic vehicle. There were nine steps represented within this test, demonstrating one-half of a weighted arm cycle or weight circumference. These steps were performed at quasi-static positions, without any concern about inertia, dynamics, or any sort of active rocking motion. At slow speeds these steps relate to reality, but at higher speeds may be different;
The computer model used was a multi-rigid body model where the wheels, car body, and arm are all treated as individual bodies. The equations were formulated using a well established technique in the multibody systems based on a generalization of Jourdain's Principle which yields the correct system equations of motion in a form which is particularly efficient and suitable for computer simulation. The equations of motion were actually developed with the aid of the software package “AUTOLEV” brand name which is marketed by Online Dynamics, Inc. This is a particularly versatile tool which was chosen for this problem because of its versatility, and the associated visualization software “ANIMAKE” brand name, which in combination made the simulation and visualization of this interesting problem straight forward.
The computer model itself used a generalized velocity projections method, popularly referred to as “Kane's Method”. Projection methods such as this are the dominant methods used for the efficient and accurate modeling of large scale, industrial scope problems. The model allows virtually all dimensions, wheel angles, and body masses to be varied easily and there effects investigated. The motor speed which moves the arm at a prescribed rate relative to the car is an infinitely variable user input. The wheel interaction with the ground is through a Hertzian contact model which the user can vary to represent different ground contact surface materials. Computer wheel to ground (tangential component) friction is also included. The friction model which is used is more elaborate than a simple coefficient of friction model, being both a nonlinear function of wheel speed and contact model penetration. This computer model could accommodate the representation of smooth, rough, dry, lubricated, soft or hard surfaces. The model is sufficiently general that it is capable of capturing behaviors such as wheel sliding, impacts, and the potential tumbling or flipping of the vehicle.
Parameter Testing: There are six parameters that have significant impact on the overall performance of the computer model. They are: a. arm height; b. end mass; c. rotational rate of the arm; d. wheelbase length; e. wheel size; f. wheel track width. All of these parameters were varied individually over a range of values that determined the extremes, which were defined by unusable performance. The results of these modeling in the “AUTOLEV” brand name program are given in Table 1 below. The computer working prototype model was used as the nominal case. The results were judged upon visual inspection of the “ANIMAKE” brand name computer display program. A nominal case, an optimized case, as well as several of the more interesting (yet unusable) sets of parameters are summarized in Tables below.
There is a broad working range for each of the six parameters tested. This speaks highly about the robustness of the overall invention. There is great robustness in the concept and there is no parameter on the knife edge ready to be a major issue if any parameter varies slightly. This overall robustness is highly desired. The working prototype of
While the present invention 10, 100 has been disclosed with respect to the described and illustrated embodiments, it is to be understood that the invention is not to be limited to those embodiments. Accordingly, reference should be made primarily to the following claims rather than the foregoing description to determine the scope of the invention.
This Application claims the benefit of U.S. Provisional Patent Application Ser. No. 60/733,320 that was filed on Nov. 3, 2005, entitled “Vehicle Having A Non-Circular Wheels Propelled By A Moving Weight”.
| Number | Name | Date | Kind |
|---|---|---|---|
| 1511928 | Zboril | Oct 1924 | A |
| 2711221 | Kopczynski | Jun 1955 | A |
| 2786540 | Sfredda | Mar 1957 | A |
| 2886976 | Dean | May 1959 | A |
| 3196580 | Rakestraw | Jul 1965 | A |
| 3311184 | Beck | Mar 1967 | A |
| 3584515 | Matyas | Jun 1971 | A |
| 3782751 | Williams | Jan 1974 | A |
| 4662465 | Stewart | May 1987 | A |
| 4817747 | Kopczynski | Apr 1989 | A |
| 4834200 | Kajita | May 1989 | A |
| 4884465 | Zachystal | Dec 1989 | A |
| 5088949 | Atkinson et al. | Feb 1992 | A |
| 5090260 | Delroy | Feb 1992 | A |
| 5361186 | Tanie et al. | Nov 1994 | A |
| 5720644 | Ku | Feb 1998 | A |
| 5758734 | Hong et al. | Jun 1998 | A |
| 5881831 | Harvey | Mar 1999 | A |
| 6308791 | Spletzer et al. | Oct 2001 | B1 |
| 20020179342 | Quinn et al. | Dec 2002 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 60733320 | Nov 2005 | US |
