Patent Application
20130084774
This specification relates to devices that move based on oscillatory motion and/or vibration, autonomous devices that can be partially controlled using magnetic fields, and tracks for devices.
One example of vibration driven movement is a vibrating electric football game. A vibrating horizontal metal surface induced inanimate plastic figures to move randomly or slightly directionally. More recent examples of vibration driven motion use internal power sources and a vibrating mechanism located on a vehicle.
One method of creating movement-inducing vibrations is to use rotational motors that spin a shaft attached to a counterweight. The rotation of the counterweight induces an oscillatory motion. Power sources include wind up springs that are manually powered or DC electric motors. The most recent trend is to use pager motors designed to vibrate a pager or cell phone in silent mode. Vibrobots and Bristlebots are two modern examples of vehicles that use vibration to induce movement. For example, small, robotic devices, such as Vibrobots and Bristlebots, can use motors with counterweights to create vibrations. The robots' legs are generally metal wires or stiff plastic bristles. The vibration causes the entire robot to vibrate up and down as well as rotate. These robotic devices tend to drift and rotate because no significant directional control is achieved.
Vibrobots tend to use long metal wire legs. The shape and size of these vehicles vary widely and typically range from short 2″ devices to tall 10″ devices. Rubber feet are often added to the legs to avoid damaging tabletops and to alter the friction coefficient. Vibrobots typically have 3 or 4 legs, although designs with 10-20 exist. The vibration of the body and legs creates a motion pattern that is mostly random in direction and in rotation. Collision with walls does not result in a new direction and the result is that the wall only limits motion in that direction. The appearance of lifelike motion is very low due to the highly random motion.
Bristlebots are sometimes described in the literature as tiny directional Vibrobots. Bristlebots use hundreds of short nylon bristles for legs. The most common source of the bristles, and the vehicle body, is to use the entire head of a toothbrush. A pager motor and battery complete the typical design. Motion can be random and directionless depending on the motor and body orientation and bristle direction. Designs that use bristles angled to the rear with an attached rotating motor can achieve a general forward direction with varying amounts of turning and sideways drifting. Collisions with objects such as walls cause the vehicle to stop, then turn left or right and continue on in a general forward direction. The appearance of lifelike motion is minimal due to a gliding movement and a zombie-like reaction to hitting a wall.
In general, one innovative aspect of the subject matter described in this specification can be embodied in apparatus (e.g., a toy vehicle) that includes a motor, a battery, a switch adapted to connect the battery to the motor, a plurality of wheels adapted to contact and roll on a surface, a vibrating mechanism connected to the motor, and at least one driving leg. Vibration caused by the vibrating mechanism causes the at least one driving leg to move the vehicle across the surface.
These and other embodiments can each optionally include one or more of the following features. The one or more driving legs are curved toward a rear end of the vehicle. The vehicle includes a single driving leg. The single driving leg is laterally centered and/or located toward a front end of the vehicle. The one or more driving legs are constructed from a rubber material or other elastomer. The motor is a rotational motor and the vibrating mechanism includes an eccentric load adapted to be rotated by the rotational motor. The rotational motor includes a housing and the eccentric load includes a counterweight disposed within the housing. The housing of the rotational motor includes two flat, round sides connected by a cylindrical portion. The motor includes a rotational axis perpendicular to a direction in which the vehicle is adapted to move and parallel to a surface that supports the vehicle. The motor is adapted to rotate in a clockwise direction when viewed from the right side of the vehicle. The vehicle includes a chassis, with the motor, battery, switch, and at least one driving leg connected to the chassis. The chassis includes holes for receiving axles for the wheels. The chassis includes multiple holes adapted to support multiple alternative wheelbases. One or more of the holes for receiving an axle are slotted to allow a corresponding axle to move vertically as the toy vehicle hops. The switch includes a reed switch adapted to be actuated by a magnet adjacent to the vehicle. The vehicle replicates a production vehicle and has dimensions of smaller than 1:75 scale of the production vehicle. The vehicle has a length of less than 2 inches and a width of less than 1 inch. The plurality of wheels include front wheels and back wheels, with the motor situated longitudinally between the front wheels and the back wheels. The motor is centered laterally in the vehicle. The motor is located as far forward as the vehicle type allows to maximize energy transfer to the legs. The motor is skewed to one side to allow for off center gearing. The vehicle includes a rear axle adapted to engage the back wheels and the battery is situated longitudinally over the rear axle. The battery is situated toward the back of the vehicle relative to the motor. The battery is situated longitudinally between the front wheels and the back wheels. The plurality of wheels includes a rubber circumferential surface. The plurality of wheels are constructed from a plastic material.
In general, another aspect of the subject matter described in this specification can be embodied in apparatus that include a motor adapted to induce motion of the vehicle, a battery, a reed switch adapted to connect the battery to the motor or disconnect the battery from the motor based on a magnetic field in a vicinity of the vehicle, and a plurality of wheels.
In general, another aspect of the subject matter described in this specification can be embodied in a system that includes at least one intersection component having a plurality of connectors adapted to interconnect the intersection component with at least one other track component. Each of the components include at least one lane and the intersection component includes a magnet selectively moveable between at least a first location underneath a first lane and second location defining one of a retracted position or a second location underneath a second lane. A selectively moveable magnet is included in a modular interactive device that can be selectively attached to a track component.
These and other embodiments can each optionally include one or more of the following features. The magnet is adapted to actuate a reed switch included in a toy vehicle as the toy vehicle moves on the first lane when the magnet is in the first location. The magnet is adapted to rotate about an axis perpendicular to a surface on which the toy vehicle moves. The magnet is indirectly coupled to a knob adapted to rotate the magnet between at least the first position and the second position. The intersection component includes detents adapted to tend to maintain the magnet in each of the first position and the second position. The intersection component includes a three-way intersection. The intersection component includes a curved wall portion adapted to cause a toy vehicle to turn. The intersection component includes a four-way intersection. At least one of the lanes of the intersection component includes a selectively rotatable vertical diverter adjacent to a lane wall of the intersection component, and the selectively rotatable vertical diverter is adapted to be selectively positioned at least between a first plane defined by a lane wall of the intersection component and a second plane situated at an oblique angle to the first plane. Positioning the selectively rotatable vertical diverter at an oblique angle to the first plane is adapted to cause a toy vehicle to change direction. Positioning the selectively rotatable vertical diverter at an oblique angle to the first plane is adapted to cause a toy vehicle to turn toward a lane having a different direction. The intersection component includes a set of one or more main lanes and a set of one or more secondary lanes and the first position of the magnet is beneath a particular one of the secondary lanes. The magnet is coupled to a button for lowering the magnet, with the second position located farther beneath the particular secondary lane than the first position. The system further includes a plurality of straight track components and a plurality of curved track components, and each of the components is adapted to connect to at least one of the other components. A vehicle includes a reed switch adapted to connect and disconnect a battery of the vehicle from a motor of the vehicle based on proximity to a magnet. The vehicle includes a motor, a battery, a switch adapted to connect the battery to the motor, a plurality of wheels adapted to contact and roll on a surface, a vibrating mechanism connected to the motor, and at least one driving leg, wherein vibration caused by the vibrating mechanism causes the at least one driving leg to move the vehicle across the surface. At least a portion of the one or more track components include a first surface feature adapted to contact the at least one driving leg when any number of the plurality of wheels are in contact with the surface and at least a portion of the one or more track components include a second surface feature adapted to avoid contact with the at least one driving leg when any number of the plurality of wheels are in contact with the surface. A curved two-lane track has a raised solid lane divider to keep cars on the inside lane in their lane. A straight two-lane track includes a dashed lane divider so one car can be diverted to the opposite lane when car collisions occur in a single lane.
In general, another aspect of the subject matter described in this specification can be embodied in methods that include inducing vibration of a toy vehicle having a vibration drive to cause the toy vehicle to move using one or more driving appendages contacting a first surface of a track and wheels contacting the track and at least one of: allowing the toy vehicle to roll on the wheels based on a second surface of the track being adapted to preclude contact with the one or more driving appendages, or causing the vehicle to stop using a magnet connected to the track, wherein the magnet causes actuation of a reed switch that connects a battery to a motor of the vehicle.
In general, another aspect of the subject matter described in this specification can be embodied in a vehicle or other apparatus that includes a battery; a plurality of wheels, wherein at least one wheel is adapted to contact and roll on a surface; a vibrating mechanism connected to the battery; and at least one driving leg. Vibration caused by the vibrating mechanism causes the at least one driving leg to move the vehicle across the surface.
These and other embodiments can each optionally include one or more of the following features. The vibrating mechanism includes a motor and a counterweight adapted to be oscillated by the motor. The at least one driving leg is curved toward a rear end of the vehicle. The toy vehicle includes a single driving leg. The single driving leg is at least one of laterally centered or located toward a front end of the vehicle. The vehicle includes a pair of driving legs. The pair of driving leg are located toward a front end of the vehicle and are laterally spaced inside of a pair of front wheels. The at least one driving leg is constructed from a rubber material, elastomer or thermoplastic elastomer. The vibrating mechanism includes a rotational motor having a housing and a counterweight disposed within the housing and adapted to be rotated by the rotational motor, with the housing of the rotational motor including two flat, round sides connected by a cylindrical portion. The vibrating mechanism comprises a rotational motor and a counterweight adapted to be rotated by the rotational motor, with the counterweight adapted to be rotated about an axis perpendicular to a direction in which the vehicle is adapted to move and parallel to a surface that supports the vehicle. A center of mass of the counterweight is substantially aligned with a longitudinal centerline of the vehicle. The counterweight is situated near a front axle of the vehicle that supports a pair of front wheels. A rotational axis of the counterweight is substantially aligned with a front axle of the vehicle that supports a pair of front wheels. The motor includes a rotational axis perpendicular to a direction in which the vehicle is adapted to move and parallel to a surface that supports the vehicle. The motor is adapted to rotate in a clockwise direction when viewed from the right side of the vehicle. The vehicle includes a chassis, with the vibrating mechanism, battery, switch, and at least one driving leg connected to the chassis. The chassis includes holes for receiving axles for the wheels. One or more of the holes for receiving an axle are slotted to allow a corresponding axle to move vertically as the toy vehicle hops. A front linkage is connected to the chassis, wherein the linkage is attached to a pivot to allow the front wheels to move vertically as the toy vehicle hops. The front wheels are rotatably coupled to a front axle supported by the front linkage, with the front linkage having a pivot parallel to the front axle and spaced away from the front axle. The front axle engages a slot adapted to limit vertical movement of the front axle. A longitudinal offset between a leg tip and a leg base of the at least one driving leg and a vertical offset between the leg tip and the leg base of the at least one driving leg form at least a twenty-five degree angle relative to a vertical plane orthogonal to a longitudinal dimension of the vehicle. The longitudinal offset between the leg tip and the leg base of the at least one driving leg and the vertical offset between the leg tip and the leg base of the at least one driving leg form an angle relative to a vertical plane orthogonal to a longitudinal dimension of the vehicle of approximately forty degrees. A circumferential surface of at least one of the plurality of wheels is tapered smaller away from an outside edge of the wheel. A switch is adapted to be actuated by a magnet adjacent to the vehicle. The vehicle replicates a production vehicle and has dimensions of smaller than 1:75 scale of the production vehicle. The vehicle has a length of less than 2 inches and a width of less than 1 inch. The plurality of wheels include front wheels and back wheels, with the vibrating mechanism situated longitudinally between the front wheels and the back wheels. The vehicle includes a rear axle adapted to engage the back wheels and the battery is situated longitudinally over the rear axle. The battery is situated toward the back of the vehicle relative to the vibrating mechanism. The battery is situated longitudinally between the front wheels and the back wheels.
In general, another aspect of the subject matter described in this specification can be embodied in a vehicle or other apparatus that includes a battery; a plurality of wheels, wherein at least one wheel is adapted to contact and roll on a surface; a vibrating mechanism connected to the battery; and a plurality of bristles. Vibration caused by the vibrating mechanism causes the plurality of bristles to move the vehicle across the surface.
These and other embodiments can each optionally include one or more of the following features. The vibrating mechanism includes a motor and a counterweight adapted to be oscillated by the motor. The vibrating mechanism comprises a rotational motor having a housing and a counterweight disposed within the housing and adapted to be rotated by the rotational motor, with the housing of the rotational motor including two flat, round sides connected by a cylindrical portion. The vibrating mechanism comprises a rotational motor and a counterweight adapted to be rotated by the rotational motor, with the counterweight adapted to be rotated about an axis perpendicular to a direction in which the vehicle is adapted to move and parallel to a surface that supports the vehicle. A center of mass of the counterweight is substantially aligned with a longitudinal centerline of the vehicle. The counterweight is situated near a front axle of the vehicle that supports a pair of front wheels. A rotational axis of the counterweight is substantially aligned with a front axle of the vehicle that supports a pair of front wheels. The vibrating mechanism comprises a rotational motor having a rotational axis perpendicular to a direction in which the vehicle is adapted to move and parallel to a surface that supports the vehicle. The motor is adapted to rotate in a clockwise direction when viewed from the right side of the vehicle. The vehicle includes a chassis, with the vibrating mechanism, battery, and switch connected to the chassis. The chassis includes holes for receiving axles for the wheels. One or more of the holes for receiving an axle are slotted to allow a corresponding axle to move vertically as the toy vehicle moves vertically. A front linkage is connected to the chassis, wherein the front linkage is attached to a pivot to allow wheels coupled to the front linkage to move vertically as the toy vehicle moves vertically. The front wheels are rotatably coupled to a front axle supported by the front linkage, with the front linkage having a pivot parallel to the front axle and spaced away from the front axle. The front axle engages a slot adapted to allow vertical movement of the front axle. A circumferential surface of at least one of the plurality of wheels is tapered smaller away from an outside edge of the wheel. A switch adapted to be actuated by a magnet adjacent to the vehicle.
In general, another aspect of the subject matter described in this specification can be embodied in a vehicle or other apparatus that includes a motor adapted to induce motion of the autonomous vehicle; a battery; a switch adapted to connect the battery to the motor or disconnect the battery from the motor based on a signal in a vicinity of the vehicle; and a plurality of wheels.
These and other embodiments can each optionally include one or more of the following features. The switch comprises a reed switch and the signal comprises a magnetic field. The switch comprises an optical switch and the signal comprises an optical signal. The switch is adapted to receive a radio signal and the signal comprises a radio signal. The switch comprises a touch sensor and the signal comprises a contact adapted to engage the touch sensor. A circumferential surface of at least one of the plurality of wheels is tapered smaller away from an outside edge of the wheel. The vehicle includes a chassis, with the motor, battery, and switch connected to the chassis and wherein the chassis includes holes for receiving axles for the wheels, with one or more of the holes for receiving an axle being slotted to allow a corresponding axle to move vertically as the toy vehicle hops.
In general, another aspect of the subject matter described in this specification can be embodied in a track system for a toy vehicle that includes at least one intersection component having a plurality of connectors adapted to interconnect the intersection component with at least one other track component, wherein each of the components include at least one lane and the intersection component includes a magnet selectively moveable between at least a first location adjacent to a first lane and second location defining one of a retracted position or a second location adjacent to a second lane.
These and other embodiments can each optionally include one or more of the following features. The magnet is adapted to actuate a switch included in a toy vehicle as the toy vehicle moves on the first lane when the magnet is in the first location. The magnet is adapted to rotate about an axis perpendicular to a surface on which the toy vehicle moves.
In general, another aspect of the subject matter described in this specification can be embodied in a track system for a toy vehicle that includes one or more straight track components having side walls and a plurality of lanes defined by a dashed raised centerline adapted to cause vehicles traveling down one of the lanes to tend to stay within the lane.
These and other embodiments can each optionally include one or more of the following features. One or more curved track components include side walls and a substantially continuous raised centerline adapted to cause vehicles traveling down one of the lanes to tend to stay within the lane as the vehicles move through the curve, wherein each of the straight track components include connectors adapted to interconnect the track component with at least one other track component. The dashed raised centerline and the substantially continuous raised centerline are defined by an upward slope situated at least at an edge of the lane. The dashed raised centerline and the substantially continuous raised centerline are defined by a vertical protrusion having substantially vertical sides at an edge of the lane.
In general, another aspect of the subject matter described in this specification can be embodied in a track system for a toy vehicle that includes an attachment for a track component, wherein the track component includes one or more lanes and is adapted to interconnect with one or more other track components and the attachment includes a signal generating mechanism adapted to selectively generate a signal in a vicinity of a lane of the track component adjacent to the attachment and the signal is adapted to actuate a switch in a vehicle located in the lane, wherein actuation of the switch is adapted to cause power from a battery in the vehicle to be removed from a motor in the vehicle.
These and other embodiments can each optionally include one or more of the following features. The signal generating mechanism includes a magnet selectively moveable between at least a first location adjacent to a first lane and second location defining a retracted position, with the magnet being adapted to interact with a switch in the vehicle when the magnet is in the first location to cause power from the battery to be removed from the motor. The signal generating mechanism selectively generates an optical signal adapted to interact with an optical sensor in the vehicle when the vehicle is in a first lane adjacent to the signal generating mechanism to cause power from the battery to be removed from the motor. The signal generating mechanism selectively generates a radio signal adapted to interact with a radio sensor in the vehicle when the vehicle is in a first lane adjacent to the signal generating mechanism to cause power from the battery to be removed from the motor.
In general, another aspect of the subject matter described in this specification can be embodied in a track system for a toy vehicle that includes an attachment for a track component, wherein the track component includes one or more lanes and is adapted to interconnect with one or more other track components and the attachment is adapted to selectively, depending on a position of a switch included in the attachment, activate a manual switch in the vehicle when the vehicle is in a first lane adjacent to the attachment to cause power from the battery to be removed from the motor.
In general, another aspect of the subject matter described in this specification can be embodied in a track system for a toy vehicle that includes a track component including one or more lanes for autonomous vehicles and one or more parking spaces for the vehicles, wherein the track component is adapted to interconnect with one or more other track components and the track component includes a magnet adjacent to each of the one or more parking spaces, with the magnet being adapted to interact with a switch in the vehicle when the vehicle is in a corresponding parking space to cause power from the battery to be removed from the motor.
These and other embodiments can each optionally include one or more of the following features. Each of the one or more parking spaces further comprises at least one sidewall and a lower profile ridge separating the parking space from a lane of the track component.
The details of one or more embodiments of the subject matter described in this specification are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages of the subject matter will become apparent from the description, the drawings, and the claims.
Like reference numbers and designations in the various drawings indicate like elements.
Small autonomous devices, or vibration-powered vehicles, can be designed to move across a surface, e.g., a floor, table, or other relatively smooth and/or flat surface. A miniature device (e.g., made to resemble a small-scale car) can be adapted to move autonomously and turn in response to external forces (e.g., by being guided by a sidewall of a track). In addition, when the device collides with object (e.g., a wall or another vehicle), the device can be constructed to deflect in a relatively random manner. In general, the devices include a chassis, multiple wheels, one or more driving legs or driving bristles, and a vibrating mechanism (e.g., a motor or spring-loaded mechanical winding mechanism rotating an eccentric load, a motor or other mechanism adapted to induce oscillation of a counterweight or other arrangement of components adapted to rapidly alter the center of mass of the device). As a result of vibration induced by the vibrating mechanism, the one or more driving legs can propel the miniature device in a forward direction as the driving leg or legs contacts a support surface.
Movement of the miniature device can be induced by the motion of a rotational motor inside of, or attached to, the device, in combination with a rotating weight with a center of mass that is offset relative to the rotational axis of the motor. The rotational movement of the weight causes the motor and the device to which it is attached to vibrate. In some implementations, the rotation is approximately in the range of 6000-9000 revolutions per minute (rpm's), although higher or lower rpm values can be used. Alternatively, the vibration mechanism can operate to induce vibration in a non-rotational manner. As an example, the device can use the many types of vibration mechanisms that exists in many pagers and cell phones that, when in vibrate mode, cause the pager or cell phone to vibrate. The vibration induced by the vibration mechanism can cause the device to move (e.g., by rolling on the wheels) across the surface (e.g., the floor) using one or more legs or bristles (e.g., groups of bristles) that are configured to alternately flex (in a particular direction based on contact with the surface) and return to the original position as the vibration causes the device to move up and down.
Various features can be incorporated into the miniature devices. For example, various implementations of the devices can include features (e.g., shape of the leg or legs, number of legs, frictional characteristics of the leg tips, relative stiffness or flexibility of the legs, resiliency of the legs, relative location of the rotating counterweight with respect to the legs, etc.) for facilitating efficient transfer of vibrations to forward motion. The speed and direction of the device's movement can depend on many factors, including the rotational speed of the motor, the size of the offset weight attached to the motor, the power supply, the characteristics (e.g., size, orientation, shape, material, resiliency, frictional characteristics, etc.) of the one or more driving legs attached to the chassis of the device, the properties of the surface on which the device operates, the overall weight of the device, the natural oscillatory frequency of the device or the driving legs, and so on. The components of the device can be positioned to maintain a relatively low center of gravity (or center of mass) to discourage tipping (e.g., based on the lateral distance between the leg tips).
In operation, when the switch 130 is turned on, the rotational motor 115 induces vibration by rotating an internal eccentric load or counterweight in a plane that is perpendicular to the support surface 150 and aligned with the longitudinal dimension of the device 100. Thus, the rotational axis of the eccentric load is perpendicular to the direction of motion and parallel to the support surface 150. This orientation can minimize or eliminate lateral forces that can be present in other orientations of the motor 115, which in turn can help the device 100 tend to move in a straight direction. In addition, centering the motor 115 laterally can minimize or eliminate torque that can further facilitate movement in a straight direction. The rotational motor 115 can also be positioned in the longitudinal dimension between the front and rear axles 145a, 145b.
The vibration of the device 100 causes the driving leg 140 to propel the device 100 in a forward direction. In particular, the rotation of the eccentric load induces upward and downward forces (i.e., forces directed away from and toward the support surface 150). The downward force induced by the rotation of the eccentric load causes the driving leg 140 to compress and bend, and a resiliency of the leg along with the upward force induced by rotation of the eccentric load causes the device 100 to hop. The repeated compression, bending of the leg, and hopping causes the device 100 to move in a forward direction. In some cases, the hop is sufficient to cause the driving leg 140 to leave the support surface, while in other cases, the hop does not cause the driving leg 140 to leave the support surface but is sufficient to reduce friction between the driving leg 140 and the support surface. By orienting the motor 115 such that the radial motor rotation direction is clockwise when facing the right side of the device 100, a forward component of the motor force further tends to push the car forward when the driving leg 140 is off the support surface 150, and a backward component of the motor force is minimized when the driving leg 140 is in contact with the support surface and acting as a brake against backward movement. The battery 120 can also be situated toward the rear of the device 100 (e.g., above but close to the rear axle 145b), which can facilitate hopping of the front end by reducing the rotational moment of inertia about the rear axle 145b. Alternatively, in some embodiments, the battery 120 can be positioned longitudinally between the front and rear axles 145a, 145b. In addition, the device 100 can include a vertical slot (as indicated at 155) that allows the front axle 145a (and thus the front wheels 110a) to move up and down as the device 100 hops, which allows the front wheels 110a to maintain contact with the support surface 150 for at least a greater percentage of the time, thereby facilitating a tendency to move in a straight direction and also further reducing the rotational moment of inertia about the rear axle 145b as the front of the device 100 hops.
Although not shown in
Movement of the device can also be influenced by the geometry of the driving leg 140 (or legs). For example, a longitudinal offset between the leg tip (i.e., the end of the leg that touches the surface 150) and the leg base (i.e., the end of the leg that attaches to the device housing) of the driving leg(s) induces movement in a forward direction as the device vibrates. Including some curvature, at least in the driving legs, can further facilitate forward motion as the legs tend to bend, moving the device forward, when vibrations force the device downward and then spring back to a straighter configuration as the vibrations force the device upward (e.g., resulting in hopping completely or partially off the surface, such that the leg tips move forward above or slide forward across the surface 150). Speed can also be increased by altering an angle of the driving leg(s) 140 with respect to the surface 150 such that the leg(s) 140 tend to cause less hop and a greater forward push. In particular, increasing the longitudinal offset between the leg tip and the leg base (without increasing the length of the leg) can increase speed. For example, the longitudinal offset between the leg tip and the leg base can be approximately equal to a vertical offset between the leg tip and the leg base (i.e., the legs are angled back at approximately ninety degrees), although in a typical embodiment the legs are angle back at least ten degrees (e.g., fifteen degrees) and generally more than about twenty five degrees (e.g., approximately forty degrees). Lower angles (i.e., closer to vertical will tend to cause the device to hop more, while higher angles tend to cause the device to move faster.
The ability of the driving leg(s) 140 to induce forward motion can result in part from the ability of the device to vibrate vertically on the resilient legs (e.g., using a rubber material or other elastomer, using flexible plastic, or using bristles). The properties of the driving leg(s) 140, including the position of the leg base relative to the leg tip, resiliency of the leg(s) 140, amount of curvature, angle of the leg relative to a support surface, and coefficient of friction (at least for the leg tip that contacts the support surface 150), can contribute to the tendency of the driving leg(s) 140 to generate forward movement and the speed in which the device 100 tends to move. Using wheels 110 with a circumferential surface having a sufficient coefficient of friction (e.g., rubber or other elastomer) can also reduce a tendency to drift laterally. In some cases, however, at least some lateral drifting may be desirable (e.g., for turning away from obstacles and/or turning along a side wall or other guide that may be intended to cause turning of the device 100). Accordingly, wheels 110 having a relatively low coefficient of friction (e.g., wheels constructed from a relatively hard plastic) can be used.
For example, the device can also be configured to facilitate some turning when vibration induced by rotation of the eccentric load induces hopping. The hopping can further induce a vertical acceleration (e.g., away from the surface 110) and a forward acceleration (e.g., generally toward the direction of forward movement of the device 100). During each hop, the driving leg(s) 140 and the front wheels 110a can hop (with or without completely leaving the support surface 150) to allow the device 100 to turn toward one side or the other at least in response to an external lateral force (e.g., from a side wall). The tendency to facilitate turning can be increased if the geometry and/or configuration of the legs is set to increase the amplitude of hopping.
The geometry of the driving leg (s) 140 can contribute to the way in which the device 100 moves. Aspects of leg geometry include: locating the leg base in front of the leg tip, curvature of the legs, deflection properties of the legs, to name a few examples. Generally, depending on the position of the leg tip relative to the leg base, the device 100 can experience different behaviors, including the speed of the device 100. For example, if the leg tip is nearly directly below the leg base when the device 100 is positioned on a support surface 150, movement of the device 100 that is caused by vibration can be limited or precluded. This is because there is little or no slope to the line in space that connects the leg tip and the leg base. In other words, there is no “lean” in the leg 140 between the leg tip and the leg base. However, if the leg tip is positioned behind the leg base (e.g., farther from the front end of the device 100), then the device 100 can move faster, as the slope or lean of the driving leg(s) 140 is optimized, providing a leg geometry that is more conducive to movement.
The legs can be either straight or curved. Leg geometry can be defined and implemented based on ratios of various leg measurements, including leg length, diameter, and radius of curvature. One ratio that can be used is the ratio of the radius of curvature of the leg 140 to the leg's length. As just one example, if the leg's radius of curvature is 49.14 mm and the leg's length is 10.276 mm, then the ratio is 4.78. In another example, if the leg's radius of curvature is 2.0 inches and the leg's length is 0.4 inches, then the ratio is 5.0. Other leg 140 lengths and radii of curvature can be used, such as to produce a ratio of the radius of curvature to the leg's length that leads to suitable movement of the device 100. In general, the ratio of the radius of curvature to the leg's length can be in the range of 2.5 to 20.0. The radius of curvature can be approximately consistent from the leg base to the leg tip. This approximate consistent curvature can include some variation, however. For example, some taper angle in the leg(s) may be required during manufacturing of the device (e.g., to allow removal from a mold). Such a taper angle may introduce slight variations in the overall curvature that generally do not prevent the radius of curvature from being approximately consistent from the leg base to the leg tip.
Another ratio that can be used to characterize the device 100 is a ratio that relates leg length to leg diameter or thickness (e.g., as measured in the center of the leg or as measured based on an average leg diameter throughout the length of the leg and/or about the circumference of the leg). For example, the length of the leg(s) 140 can be in the range of 0.2 inches to 0.8 inches (e.g., 0.405 inches) and can be proportional to (e.g., 5.25 times) the leg's thickness in the range of 0.03 to 0.15 inch (e.g., 0.077 inch). Stated another way, leg(s) 140 can be about 15% to 25% as thick as they are long, although greater or lesser thicknesses (e.g., in the range of 5% to 60% of leg length) can be used. Leg lengths and thicknesses can further depend on the overall size of the device 100. In general, at least one driving leg can have a ratio of the leg length to the leg diameter in the range of 2.0 to 20.0 (i.e., in the range of 5% to 50% of leg length).
As discussed above, the driving leg(s) 140 can be curved. Because the leg(s) 140 are typically made from a flexible material, the curvature of the leg(s) 140 can contribute to the forward motion of the device 100. Curving the leg can accentuate the forward motion of the device 100 by increasing the amount that the leg compresses relative to a straight leg. This increased compression can also increase vehicle hopping. The driving leg(s) 140 can also have at least some degree of taper from the leg base to the leg tip.
The leg(s) 140 are generally constructed of rubber or other flexible but resilient material (e.g., polystyrene-butadiene-styrene with a durometer near 55, based on the Shore A scale, or in the range of 45-75, based on the Shore A scale). Thus, the legs tend to deflect when a force is applied. Generally, the leg(s) 140 include a sufficient stiffness and resiliency to facilitate consistent forward movement as the device vibrates. The selection of leg materials can have an effect on how the device 100 moves. For example, the type of material used and its degree of resiliency can affect the amount of bounce in the leg(s) 140 that is caused by vibration. As a result, depending on the material's stiffness (among other factors, including positions of leg tips relative to leg bases), the speed of the device 100 can change. In general, the use of stiffer materials in the leg(s) 140 can result in more bounce, while more flexible materials can absorb some of the energy caused by vibration, which can tend to decrease the speed of the device 100.
A vibration-driven wheeled vehicle, such as device 100 or device 400, or a vehicle with another drive mechanism, can be used in connection with a track system. The track system can be modular and can include components that can be assembled (e.g., snapped together using connectors) in virtually any configuration. The track system can include walls or other protrusions for guiding the vehicle along straight and curved paths. In addition, some protrusions or guide members can be selectively positioned to cause different behaviors (e.g., turning or going straight). The track system can also include built-in magnets that can be used to actuate a reed switch in the vehicles to cause the vehicles to stop. Such magnets can be selectively moved closer to or farther away from vehicles that are adjacent to (e.g., above or beside) the magnet to selectively actuate or de-actuate such reed switches. The components of the track system can include one or more lanes.
In some implementations, a track system can include inclines or declines. By including surface features on the track that at least substantially prevent one or more driving legs from contacting the surface, it is possible to allow a vibration-driven wheeled device to freely roll (e.g., downhill).
As an alternative, a flat surface can be used instead of a groove 2005 to allow the device to roll freely, if a shorter driving leg of the device is used. In such a case, portions of the track can include a raised feature that engages with the driving leg to enable the driving leg to propel the device.
Thus, particular embodiments of the subject matter have been described. Other embodiments are within the scope of the following claims.
This application claims the benefit under 35 U.S.C. §119(e) of U.S. Patent Application No. 61/543,047, entitled “Vibration Powered Vehicle,” filed Oct. 4, 2011, which is incorporated herein by reference in its entirety.
| Number | Date | Country | |
|---|---|---|---|
| 61543047 | Oct 2011 | US |
