Autonomous vehicles, such as vehicles that do not require a human driver, can be used to aid in the transport of passengers or items from one location to another. Such vehicles may operate in a fully autonomous mode where passengers may provide some initial input, such as a pick up or destination location, and the vehicle maneuvers itself to that location.
A component of an autonomous vehicle is the perception system, which allows the vehicle to perceive and interpret its surroundings using cameras, radar, sensors, and other similar devices. Data from the perception system is then used by the autonomous vehicle's computer to make numerous decisions while the autonomous vehicle is in motion, such as deciding when to speed up, slow down, stop, turn, etc. These decisions are used to maneuver between locations, but also to interact with and avoid collisions with other objects along the way.
In advance of, or upon a collision non-autonomous and autonomous vehicles alike may deploy various safety mechanisms to reduce injury to passengers and pedestrians. Typically, the safety mechanisms may include airbag systems employed to protect passengers from impacts with the interior of a vehicle after an object external to a vehicle has impacted a bumper of the vehicle.
Embodiments within the disclosure relate generally to net systems to reduce the risk of injury caused by impact with a vehicle to an object or a pedestrian. The system may comprise a net configured to deploy in a vehicle's environment in order to reduce the likelihood of an object colliding directly with a vehicle and one or more energy reduction structures arranged on the net, wherein the one or more energy reduction structures are configured to reduce injury caused by impact of the object by absorbing impact energy.
In some embodiments the one or more energy reduction structures may include at least one link breaking device. The at least one link breaking device may be configured to tear apart at a predetermined tension threshold.
In some embodiments the one or more energy reduction structures include at least one hobbling string. The one hobbling string may be configured to tear apart at a predetermined tension threshold.
In some embodiments the net may be configured to deploy within the vehicle's interior environment.
In some embodiments the one or more energy reduction structures may include one or more slip knots. The one or more slip knots may include at least one net anchor slip knot, the at least one net anchor slip knot securing the net to one or more supports. The one or more energy reduction structures may further include at least one other energy reduction structure. The one or more slip knots may include basic slip knots, pop-stop slip knots. The one or more slip knots may be positioned throughout the net.
In some embodiments the net is positioned on the vehicle.
In some embodiments the net is stored in a compartment attached to the vehicle.
Another aspect may include a method for deploying a net in a vehicle's vicinity in order to reduce the likelihood of an object colliding directly with the vehicle. The method may include determining, by one or more processors, a collision with the object is imminent. The one or more processors may predict a location on the vehicle where the collision with the object is expected to occur and determine a first net at the location on the vehicle where the collision is expected to occur. The one or more processors may send a triggering signal to deploy the first net and in response to receiving the triggering signal, deploying by one or more processors, the first net, wherein the first net includes at least one energy reduction structure arranged on the first net, wherein the at least one energy reduction structure is configured to reduce injury caused by impact of the object by absorbing impact energy.
This technology relates to an external net system which reduces the potential of impact injuries to pedestrians or other objects impacted by a vehicle. For example, in the event of a vehicle impact with a pedestrian, considerable injury may result to the pedestrian. Computing devices within a vehicle may determine that an impact with an object, such as a pedestrian, cannot be avoided by way of decelerating, steering, and/or accelerating the vehicle. When this is the case, the computing devices may deploy an external net across the vehicle to absorb the impact of the pedestrian and stop the pedestrian from making direct contact with the vehicle. This in turn may help reduce impact injuries to the pedestrian and in some cases, save lives.
Prior to deployment, an external net system may be mounted in a compartment arranged at various locations on a vehicle. The external net system may be comprised of multiple components including at least one net. The net may be attached to one or more supports also arranged within the compartment. The supports may be configured to hold the net in a deployed position such that the net blocks the pedestrian from making contact with the vehicle. The external net system may further include a deployment tool to accomplish deployment of the supports and/or the net from a compartment.
The net may made from cordage or webbing. The net may also be comprised of a strong fabric, nylon, polyester, or other similar material. The net may be of various shapes, such as, for example, square, rectangular, trapezoidal, triangular, oval, etc.
The net may be situated between the supports of the external net system. For example one side of the net may be attached across a portion of a first support extending between a base of the first support to a top portion of the first support. An opposite side of the net may be attached across a portion of a second support extending from around a base of the second support to a top portion of the second support.
The net may be attached to the supports using various attachment tools, such as cable ties, adhesives, clips, clamps, anchors, hooks, snaps, hook and loop straps, cords looped into holes in the supports, sleeves on each side of the net, etc. In an example, the net may be attached to the supports using net anchor slip knots. In this regard, the strands of the net may be terminated with slip knots and attached to the supports.
Upon impact with a pedestrian, the tension in the strands of the net may increase, thereby causing the strands to slip through the knots. The strands may slip through the knots until the knots are taut against the support.
The energy absorption of the slip knots may be adjusted based on the length of the loop of the slip knot. In this regard, the string, or other material, which comprises the knot will untie and lengthen upon a force being applied. As the slip knot unties, energy is absorbed by the net.
Slip knots may be included throughout the body of the net. For example, slip knots may be spaced evenly throughout the net, although the spacing of the slip knots may be uneven. The number and placement of slip knots throughout the net may be dependent upon the amount of energy absorption needed. In this regard, the more slip knots within the net, the more energy the net will absorb as the slip knots unwind.
Hobbling strings may be included throughout the body of the net to absorb impact energy. Hobbling strings may be designed to break at a predetermined tension. For example, hobbling strings may be attached to nodes of the net to bring the nodes of the net closer together. Upon impact with a pedestrian, a predetermined impact threshold may be reached, causing the hobbling strings to break and allowing the net to absorb energy in this breaking. A net may include hobbling strings designed to break at different tensions, to allow for controlled energy absorption.
The net may include link breaking devices to absorb impact energy. In this regard, section of the net may be overlapped and stitched together. For example, sections of the net may be overlapped and stitched together to form a link breaking device. Upon the link breaking device experiencing a predetermined level of tension, the stitches may break resulting in the lengthening of the net. Dependent upon the strength of the stitching material, the level of tension required to break the link breaking device may be adjusted, thereby allowing for controlled release of the link breaking device.
The features described herein may allow for improved safety in and around a vehicle. In this regard, the vehicle may offer safety measures to individuals and objects outside of the vehicle such that the vehicle can operate in environments close to pedestrians and other external objects with a reduced chance of causing injury or damage to the pedestrians or objects in the case of an inadvertent collision. Additionally, the features described herein may allow for improved safety of passengers inside of the vehicle. In this regard, the safety measures may be positioned within the interior of the vehicle to reduce the chance of injury or damage to the passengers in the case of an inadvertent collision.
In addition, as discussed in detail below, the features described herein allow for various alternatives.
As shown in
The memory 130 stores information accessible by the one or more processors 120, including instructions 132 and data 134 that may be executed or otherwise used by the processor 120. The memory 130 may be of any type capable of storing information accessible by the processor, including a computing device-readable medium, or other medium that stores data that may be read with the aid of an electronic device, such as a hard-drive, memory card, ROM, RAM, DVD or other optical disks, as well as other write-capable and read-only memories. Systems and methods may include different combinations of the foregoing, whereby different portions of the instructions and data are stored on different types of media.
The instructions 132 may be any set of instructions to be executed directly (such as machine code) or indirectly (such as scripts) by the processor. For example, the instructions may be stored as computing device code on the computing device-readable medium. In that regard, the terms “instructions” and “programs” may be used interchangeably herein. The instructions may be stored in object code format for direct processing by the processor, or in any other computing device language including scripts or collections of independent source code modules that are interpreted on demand or compiled in advance. Functions, methods and routines of the instructions are explained in more detail below.
The data 134 may be retrieved, stored or modified by processor 120 in accordance with the instructions 132. For instance, although the claimed subject matter is not limited by any particular data structure, the data may be stored in computing device registers, in a relational database as a table having a plurality of different fields and records, XML documents or flat files. The data may also be formatted in any computing device-readable format.
The one or more processor 120 may be any conventional processors, such as commercially available CPUs. Alternatively, the one or more processors may be a dedicated device such as an ASIC or other hardware-based processor. Although
Computing device 110 may all of the components normally used in connection with a computing device such as the processor and memory described above as well as a user input 150 (e.g., a mouse, keyboard, touch screen and/or microphone) and various electronic displays (e.g., a monitor having a screen or any other electrical device that is operable to display information). In this example, the vehicle includes an internal electronic display 152 as well as one or more speakers 154 to provide information or audio visual experiences. In this regard, internal electronic display 152 may be located within a cabin of vehicle 100 and may be used by computing device 110 to provide information to passengers within the vehicle 100.
Computing device 110 may also include one or more wireless network connections 154 to facilitate communication with other computing devices, such as the client computing devices and server computing devices described in detail below. The wireless network connections may include short range communication protocols such as Bluetooth, Bluetooth low energy (LE), cellular connections, as well as various configurations and protocols including the Internet, World Wide Web, intranets, virtual private networks, wide area networks, local networks, private networks using communication protocols proprietary to one or more companies, Ethernet, WiFi and HTTP, and various combinations of the foregoing.
In one example, computing device 110 may be an autonomous driving computing system incorporated into vehicle 100. The autonomous driving computing system may capable of communicating with various components of the vehicle. For example, returning to
As an example, computing device 110 may interact with deceleration system 160 and acceleration system 162 in order to control the speed of the vehicle. Similarly, steering system 164 may be used by computer 110 in order to control the direction of vehicle 100. For example, if vehicle 100 is configured for use on a road, such as a car or truck, the steering system may include components to control the angle of wheels to turn the vehicle. Signaling system 166 may be used by computing device 110 in order to signal the vehicle's intent to other drivers or vehicles, for example, by lighting turn signals or brake lights when needed.
Navigation system 168 may be used by computing device 110 in order to determine and follow a route to a location. In this regard, the navigation system 168 and/or data 134 may store detailed map information, e.g., highly detailed maps identifying the shape and elevation of roadways, lane lines, intersections, crosswalks, speed limits, traffic signals, buildings, signs, real time traffic information, vegetation, or other such objects and information.
Positioning system 170 may be used by computing device 110 in order to determine the vehicle's relative or absolute position on a map or on the earth. For example, the position system 170 may include a GPS receiver to determine the device's latitude, longitude and/or altitude position. Other location systems such as laser-based localization systems, inertial-aided GPS, or camera-based localization may also be used to identify the location of the vehicle. The location of the vehicle may include an absolute geographical location, such as latitude, longitude, and altitude as well as relative location information, such as location relative to other cars immediately around it which can often be determined with less noise that absolute geographical location.
The positioning system 170 may also include other devices in communication with computing device 110, such as an accelerometer, gyroscope or another direction/speed detection device to determine the direction and speed of the vehicle or changes thereto. By way of example only, an acceleration device may determine its pitch, yaw or roll (or changes thereto) relative to the direction of gravity or a plane perpendicular thereto. The device may also track increases or decreases in speed and the direction of such changes. The device's provision of location and orientation data as set forth herein may be provided automatically to the computing device 110, other computing devices and combinations of the foregoing.
The perception system 172 also includes one or more components for detecting objects external to the vehicle such as other vehicles, obstacles in the roadway, traffic signals, signs, trees, etc. For example, the perception system 170 may include lasers, sonar, radar, cameras and/or any other detection devices that record data which may be processed by computing device 110. In the case where the vehicle is a small passenger vehicle such as a car, the car may include a laser sensor 214 (shown in
The computing device 110 may control the direction and speed of the vehicle by controlling various components. By way of example, computing device 110 may navigate the vehicle to a destination location completely autonomously using data from the detailed map information and navigation system 168. Computing device 110 may use the positioning system 170 to determine the vehicle's location and perception system 172 to detect and respond to objects when needed to reach the location safely. In order to do so, computing device 110 may cause the vehicle to accelerate (e.g., by increasing fuel or other energy provided to the engine by acceleration system 162), decelerate (e.g., by decreasing the fuel supplied to the engine, changing gears, and/or by applying brakes by deceleration system 160), change direction (e.g., by turning the front or rear wheels of vehicle 100 by steering system 164), and signal such changes (e.g., by lighting turn signals of signaling system 166). Thus, the acceleration system 162 and deceleration system 162 may be a part of a drivetrain that includes various components between an engine of the vehicle and the wheels of the vehicle. Again, by controlling these systems, computing device 110 may also control the drivetrain of the vehicle in order to maneuver the vehicle autonomously.
The sensors of perception system 172 may detect objects in the vehicle's environment as well as characteristics of those objects such as their location, heading, size (length height and width), type, and approximate center of gravity. For example, the perception system may use the height of an object identified as a pedestrian (or human) to estimate the approximate center of gravity of the object. In this regard, the perception system may compare the characteristics of the object to known anthropomorphic data to determine an approximate center of gravity. For other object types, the approximate center of gravity may be determined from the characteristics of the object using various known statistical analyses. Data and information required for these determinations may be stored, for example, in memory 130 or a different memory of the perception system.
As discussed in more detail below, information from the perception system may be sent to various other systems in order to make decisions about when and how to deploy various safety mechanisms. In this regard, the perception system may send the information to the vehicle's computing devices which make such decisions and forward activation instructions to protection system 174 which deploys one or more safety mechanisms 176 in accordance with the activation instructions. In another example, the perception system 172 may forward the information directly to the protection system 174 which makes then determines whether and how to deploy one or more safety mechanisms 176.
Thus, the vehicle may also include a plurality of safety mechanisms 176. These safety mechanisms may be configured to reduce the likelihood of damage to objects outside of the vehicle as opposed to those meant to specifically protect passengers inside the vehicle. At least some of these safety mechanisms may be active, in that the device must be activated or deployed by a signal generated by one or more computing devices when an impact is imminent.
The one or more safety mechanisms 176 may include one or more external net systems. An external net system may be mounted in a compartment arranged at various locations on a vehicle. For example, an external net system 201 may be mounted in the interior of a front portion 220 of the vehicle 100, as shown in
The external net system may be comprised of multiple components. For instance, the external net system may include at least one net. The net may be attached to one or more supports also arranged within the compartment. For example, as shown in
The net may be a traditional net, such as a net made from strands of cordage or webbing. In this regard, the strands may be woven or combined together to form webbing of the net. The net may also be a sheet of a strong fabric, nylon, polyester, or other similar material. The net may be of various shapes. For example, the net 206 may be square, rectangular, trapezoidal, triangular, oval, etc. The net may also contain energy reduction structures, which may assist in dissipating impact energy.
The net may be backed by a thin fabric to prevent entanglement during deployment. In this regard, the thin fabric may prevent the cordage or webbing from becoming tangled when in a stored position. The thin fabric may also include energy reduction structures, such as knots and link breaking devices, to further increase the energy absorption during impact with an object.
Portions of the net may be attached to the supports. For example, as shown in
The net may be attached to the supports using various attachment tools, such as cable ties, adhesives, clips, clamps, anchors, hooks, snaps, hook and loop straps, cords looped into holes in the supports, sleeves on each side of the net, etc. Additionally, the net may be attached to the supports using and energy reduction structure such as a net anchor slip knot. For example, the strands of the net 406, which is an example configuration of the net 206, may be terminated with a net anchor slip knot and attached to the supports as shown in
Upon a pedestrian, passenger, or object impacting the net, the tension in the strands of the net may increase. The tension may cause the strands to slip through the net anchor slip knots until the knots are taut against the support. For example, as further shown in
Energy reduction structures such as basic slip knots, pop-stop slip knots, link breaking devices, hobbling strings, etc., may also be used as energy reduction structures within the net. As shown in
The pop-stop slip knot prevents the knot from untying, thereby avoiding the additional, non-energy absorbing extension of the strand as occurs in a basic slip knot. For instance, as shown in
As noted above, slip knots, including pop-stop slip knots and basic slip knots, may be positioned within the net. For example, as shown in
Again, the number and placement of slip knots within the net may be dependent upon the amount of energy absorption needed. In this regard, the more slip knots within the net, the more energy the net will absorb as the slip knots unwind. In addition, the energy absorption of the slip knots may be adjusted based on the length of the loop used to make the slip knot. As described herein, the string, or other material, which comprises the slip knot will untie causing the string to lengthen upon a force being applied. As the slip knot unties, energy is absorbed by the net. For, a typical slip knot may be around 6.5 times the size of the loop, with longer loops lengthening the net more than smaller loops. Accordingly, longer loops will allow more energy absorption than smaller loops, as more energy is required to fully lengthen a slip knot with a larger loop. For net anchor slip knots, the energy absorption may be adjusted based on the length of the strands which pass through the net anchor slip knots before they contact the support.
Slip knots may be formed from two or more strands of a net. In this regard, each strand may include one or more slip knots which include one or more loops through which an adjacent strand may pass. Upon impact with an object, the strands may be pulled through their respective slip knots, thereby absorbing energy. For example, as shown in
Upon a force being applied to the net, the multiple strands may slip through the loops of the knots through which they are threaded. For instance, as shown in
In addition or alternatively, hobbling strings may be used as energy reduction structures within the net. In this regard, hobbling strings may be attached to nodes of a net, thereby causing the nodes to be positioned closer together than if no hobbling strings were attached to the net. The hobbling strings may absorb impact energy by breaking at a predetermined tension, thereby allowing the nodes to stretch apart. For example, hobbling strings, such as hobbling strings 922 may be attached to nodes of the net 906, which is one example configuration of the net 206, such as nodes 924, as shown in
Upon impact with a pedestrian, a predetermined impact threshold may be reached, causing the hobbling strings to break and allowing the net to absorb energy in this breaking. The predetermined impact threshold may be about 40,000 N for 50% of the male population, or more or less and may be dependent upon the number of cables in the net. For instance, a force 951 may be applied to the net 906 upon an object colliding with the net as shown in
In addition or alternatively, the net may include link breaking (e.g., stitch ripping) devices to absorb impact energy. In this regard, section of the net may be overlapped and stitched together. Upon the link breaking device experiencing a predetermined level of tension, the stitches may break resulting in the lengthening of the net. Dependent upon the strength of the stitching material, the level of tension required to break the link breaking device may be adjusted, thereby allowing for controlled release of the link breaking device.
For example,
In another embodiment, the net may be attached to the supports via a cable as shown in
The supports may be in various shapes. For example, the supports maybe tubes, plates, solid structures, hollow structures, etc. The cross section of the supports may be circular, oval, rectangular, polygonal, etc.
The supports may also be configured to project from the vehicle upon deployment. In this regard, the supports may telescope, swing, or otherwise release from their stowed position to an erected position. For example, as shown in
The telescoping tubes may expand vertically upwards from a stowed position to an open position upon detection of an impact. In this regard, prior to the impact, the telescoping tubes 1201 may remain in a stowed position within a compartment, as shown in
In some embodiments the supports may be configured to swing into a deployed position, thereby extending the net across the vehicle. In this regard, the supports may be in the shape of tubes, telescoping tubes, plates, etc. The supports may be made of metal or other such hard materials, such as aluminum, iron, copper, nickel, tin, carbon fiber, etc. The supports maybe positioned on a portion of the vehicle horizontally relative to a ground on which the vehicle is positioned. The base of a support may be mounted to the vehicle at a pivot point. The support may be configured to swing up, pivoting about the pivot point, to a vertical position relative to the ground. When a vertical position is reached, the supports may come to a stop upon contact with a stopper. For example, the stopper may be an internal bumper, a latch, a sprawl, etc.
For example, as shown in
The supports may be configured to pivot toward the vehicle on contact with a pedestrian when in the vertical position after deployment. In this regard, the pivot point may be augmented by a spring to provide resistance after an impact with a pedestrian. The spring may be torsional or linear. For example, as shown in
As noted above, a deployment tool may be used to accomplish the deployment of the supports and/or the net. The deployment tool may include springs, compressed gas devices, pyrotechnic devices, pumps, pneumatics, electrical actuators, etc. to release supports from a stowed position to a deployed position. For example, spring 1320 shown in
Once deployed, the net may be extended between supports. Upon impact, a portion of the pedestrian's body may contact the net instead of directly contacting parts of the vehicle, reducing contact forces and hence injury. For example, as shown in
In addition or alternatively to locations at the front end of the vehicle, a compartment may be located within the rear bumper or trunk of the vehicle, within the vehicles doors, arranged in, across, or below a hood panel under a cosmetic cover (as shown in
In some embodiments, the net maybe configured to reduce secondary impact. After the initial impact with the vehicle, a pedestrian may be ejected from (or bounce off of) the external net system in a direction opposite of the direction of the initial impact with the next. As such, the pedestrian may be susceptible to secondary impact injuries, as the pedestrian may hit the ground or another object after being ejected. To minimize or even eliminate the secondary potential impact injuries, the net maybe configured to close in around the pedestrian, or be coated in an adhesive to help retain or slow the release of the pedestrian from the net to reduce injuries caused by a secondary impact. For example, the supports may be configured to bend and lock with one another after the impact, thereby containing the pedestrian within the net. The net may be coated in an adhesive to help retain or slow the release of the object from the net or at least absorb some of the secondary impact forces by slowing the release of the pedestrian from the external net system upon the pedestrian rebounding from the initial impact.
In some embodiments, the external net system may be designed to protect a pedestrian's lower extremities. For example, as shown in
In some embodiments, external airbags may be used in conjunction with the external net system to provide additional protection to the pedestrian. For example, as shown in
In some embodiments, instead of the supports, only airbags may be placed on the hood of the vehicle. For example, as shown in
In some embodiments, triangular structures maybe used as supports. For example, as shown in
In some examples, airbags maybe used as supports. For example, as shown in
In another embodiment, the net maybe attached to the underside of a vehicle panel, such as a hood, trunk, fender, etc. This configuration may eliminate the need for the supports. For example, as shown in
In addition to the operations described above and illustrated in the figures, various operations will now be described. It should be understood that the following operations do not have to be performed in the precise order described below. Rather, various steps can be handled in a different order or simultaneously, and steps may also be added or omitted.
Deployment of the external net system may be done selectively. For instance, deployment may occur in response to a collision or in anticipation of collision based on information from sensors of the vehicle that detect and identify objects in the vehicle's external environment, including pedestrians. For example, to deploy the external net system, a vehicle's computing devices may use information from the vehicle's sensors to identify and track objects in the vehicle's environment. In addition, the vehicle's computing devices may use the characteristics of the object, such as speed and heading, to predict trajectories or future locations where the object and also the vehicle will be.
In addition, the vehicle's computing devices may use the characteristics of the object, such as speed and heading, to predict future locations where the object will be. For example, as shown in example 1900 of
The vehicle's computing devices may also determine whether the future locations indicate that the vehicle will collide with the object (and also approximately where and when). For example, the perception system 174 or computing device 110 may determine that an impact with object 1110 is likely to occur at the locations of predicted impact point 1122, respectively. Each of these impact points may be defined as a three-dimensional coordinate (X, Y, Z) in space such as latitude, longitude, and altitude or similar.
In most cases, if a collision is likely, the vehicle's computing devices may maneuver the vehicle in order to avoid the object. For example, computing device 110 may use the steering, acceleration and deceleration systems to maneuver vehicle 100 out of the path of object 1110.
However if there is not enough time to avoid the object, (i.e. not enough distance, not enough braking power, not enough room to go around or avoid etc.) the vehicle's computing devices may determine that an impact with the object is imminent. For example, an impact may be imminent, when an impact is predicted to occur within a predetermined period of time, such as a few seconds or more or less. When an impact is imminent, the vehicle's computing devices may send a signal to deploy the external net system. This triggering signal may be sent for example by computing device 110, laser sensor 214, or the one or more computing devices of protection system 176.
Once the computing devices have determined to deploy the external net system, a signal from the computing devices may trigger ignition of the deployment tool to deploy the supports and/or the net. For example and referring to
Although the examples described herein are related to the use of vehicles when operating in autonomous driving modes, such features may also be useful for vehicles operating in manual or semi-autonomous modes or for vehicles having only manual driving mode and semi-autonomous driving modes. In such cases, an active safety mechanism may be identified as discussed above. However, when making the determination as to whether to deploy the active safety mechanism and/or control the vehicle as discussed above, the reaction time of the driver may be compared with the estimated time at which an impact with an object is expected to occur. Reaction times may be determined, for example, by monitoring a specific driver's reaction times over time or by using average or expected reaction times for drivers in general. If the reaction time is too slow, the vehicle's computing device may then use the estimated time when an update will be received to determine whether to deploy the active safety mechanism and, in the case of a vehicle with such capabilities to take control and maneuver the vehicle as discussed in the examples above.
Unless otherwise stated, the foregoing alternative examples are not mutually exclusive, but may be implemented in various combinations to achieve unique advantages. As these and other variations and combinations of the features discussed above can be utilized without departing from the subject matter defined by the claims, the foregoing description of the embodiments should be taken by way of illustration rather than by way of limitation of the subject matter defined by the claims. In addition, the provision of the examples described herein, as well as clauses phrased as “such as,” “including” and the like, should not be interpreted as limiting the subject matter of the claims to the specific examples; rather, the examples are intended to illustrate only one of many possible embodiments. Further, the same reference numbers in different drawings can identify the same or similar elements.