TRAILER TANDEM POSITION SENSOR

A tandem position sensing system of a vehicle includes a plurality of radio frequency identification (RFID) tags coupled to a trailer or a chassis of the vehicle and arranged along a first direction; and an RFID reader coupled to a sliding tandem of the vehicle that is moveable relative to the trailer or the chassis, the RFID reader being configured to identify a unique identifier of one the plurality of RFID tags that is proximate to the RFID reader, the unique identifier corresponding to a position of the sliding tandem relative to the trailer or the chassis.

FIELD

The present disclosure relates to truck-trailer systems and methods of using the same.

BACKGROUND

Most semi-tractor trailers in the US have sliding tandems, which are a set of 8 wheels on two axles that are moveably coupled to the rear underside of the trailer. The tandems can slide along a track under the trailer to allow for the distribution of weight of the trailer to be adjusted to support legal weight distribution, better ride control, handling, and turning radius. Some states (e.g., Michigan and California) have laws pertaining to the minimum and maximum lengths that the tandem can be adjusted to in order to alleviate concerns with semi ride control and/or road weight distribution. It is currently the responsibility of the driver to confirm that the tandem is positioned to a length that is allowed under the laws pertaining to the state in which the semi will be transiting. Violating these laws can result in Federal Motor Carrier Safety Administration (FMCSA) violations, fines, and/or other driver infractions.

Furthermore, the position of the tandem is a significant factor in the turning radius of the overall vehicle when connected to the semi-trailer. For example, a tandem set all the way to the rear of the trailer may have a significantly greater turning radius than a tandem that is set closer to the front of the trailer. As such, when entering inner cities, some drivers may adjust the tandem to provide better turning radius to avoid hitting curbs on turns in tight areas. In the related art, tandem position observations are performed manually/visually by the driver, and the process of repositioning the sliding tandem may require the driver to exit and reenter the truck cab many times to visually check the actual position of the tandem and to move the tractor, which can be tedious and time consuming.

SUMMARY

Aspects of embodiments of the present invention are directed to a tandem position sensing system including a plurality of RFID tags with unique identifications that are mounted to the underside of a trailer/chassis, and an RFID reader attached to a fixed position on the sliding tandem, which can read the unique identifiers of the RFID tags, and can translate the unique RFID identifications and their relative signal strength into a sliding tandem position (e.g., in real time). In some examples, the positions of the RFID tags and reader may be reversed, that is, the RFID tags may be coupled to the moveable tandem and the RFID reader may be connected to a fixed position at the underside of the trailer. The tandem position sensing system may further include a communication circuit capable of delivering the information gathered and analyzed to another processor that can deliver the data to the driver or autonomous truck controller to make actionable decisions from.

According to some embodiments of the present disclosure, there is provided a tandem position sensing system of a vehicle, including: a plurality of radio frequency identification (RFID) tags coupled to a trailer or a chassis of the vehicle and arranged along a first direction; and an RFID reader coupled to a sliding tandem of the vehicle that is moveable relative to the trailer or the chassis, the RFID reader being configured to identify a unique identifier of one the plurality of RFID tags that is proximate to the RFID reader, the unique identifier corresponding to a position of the sliding tandem relative to the trailer or the chassis.

In some embodiments, the sliding tandem is configured to move relative to the trailer or the chassis along the first direction, and wherein the first direction is a longitudinal direction of the trailer or the chassis.

In some embodiments, the plurality of RFID tags are fixedly coupled to a tag platform that is fixedly coupled to an underside of the trailer or the chassis, and at least an antenna of the RFID reader is fixedly coupled to a cross-bar of the sliding tandem below the tag platform.

In some embodiments, the tag platform includes at least one of a rail, a channel, or a strip, and extends along the first direction, and the plurality of RFID tags are adhered to the tag platform.

In some embodiments, the antenna of the RFID reader and the tag platform are oriented such that the RFID tags pass directly above the antenna of the RFID reader as the sliding tandem moves relative to the trailer or the chassis, and a vertical offset between the RFID reader and the tag platform is about 1 inch to about 3 inches.

In some embodiments, the plurality of RFID tags are arranged at regular intervals.

In some embodiments, the sliding tandem has a plurality of tandem locking positions, and is configured to lock in position relative to the trailer at each of the plurality of tandem locking positions, the plurality of tandem locking positions are spaced at regular intervals, and at least one of the plurality of RFID tags corresponds in position to each of the plurality of tandem locking positions.

In some embodiments, a separation between adjacent ones of the tandem locking positions is integer multiples of a separation between adjacent ones of the plurality of RFID tags.

In some embodiments, a spacing between consecutive ones of the plurality of tandem locking positions is about 4 inches to about 6 inches, and a spacing between consecutive ones of the plurality of RFID tags is about 2 inches to about 4 inches.

In some embodiments, an RFID tag of the plurality of tags includes: a tag antenna configured to transmit and receive radio frequency (RF) signals; and an integrated circuit configured to store a unique identifier of the RFID tag, to receive RF energy from the tag antenna, and to modulate the RF energy with the unique identifier to generate a modulated RF signal for transmission by the tag antenna.

In some embodiments, the RFID reader includes: a reader antenna configured to transmit and receive RF signals; and a processing circuit configured to generate an RF signal for transmission by the reader antenna, to receive a modulated RF signal from the one the plurality of RFID tags that is proximate to the RFID reader via the reader antenna, and to detect the unique identifier based on the modulated RF signal.

In some embodiments, the processing circuit is further configured to determine the position of the sliding tandem relative to the trailer or the chassis based on the unique identifier, and the unique identifier includes data indicating a corresponding tandem locking position.

In some embodiments, the processing circuit is further configured to determine the position of the sliding tandem relative to the trailer or the chassis based on the unique identifier and a lookup table.

In some embodiments, the lookup table is stored at the processing circuit and maps unique identifiers of the plurality of RFID tags to a plurality of relative positions of the sliding tandem and the trailer or the chassis.

In some embodiments, the RFID reader further includes: a communication circuit in electrical communication with a telematics gateway circuit at the trailer or the chassis of the vehicle and is configured to transmit data generated by the processing circuit to the telematics gateway circuit over a controller area network (CAN) bus of the trailer or the chassis, an RS232/485 connection, a power line communication (PLC) connection, or a wireless communication link.

In some embodiments, the RFID reader further includes: an internal battery configured to provide electrical power to the RFID reader.

In some embodiments, the RFID reader is coupled to an electrical system of the trailer or the chassis of the vehicle and receives electrical power from at least one of an electrical circuit of an anti-lock braking system (ABS) of the trailer or the chassis, a light circuit providing power to lights of the trailer or the chassis, a power-over-ethernet (PoE) connection, or a solar panel of the trailer or the chassis.

Other aspects, features, and characteristics that are not described above will be more clearly understood from the accompanying drawings, claims, and detailed description.

DETAILED DESCRIPTION

The detailed description set forth below in connection with the appended drawings is intended as a description of illustrative embodiments of a trailer system including a tandem position sensor in accordance with the present invention, and is not intended to represent the only forms in which the present invention may be implemented or utilized. The description sets forth the features of the present invention in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and structures may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the present invention. As denoted elsewhere herein, like element numbers are intended to indicate like elements or features.

Aspects of embodiments of the present disclosure are directed to a tandem position sensing system mounted to a trailer (e.g., the undercarriage of the trailer) and chassis, which is capable of measuring the position of the trailer/chassis sliding tandem and reporting this information to the driver of the vehicle and/or to a dispatch/external server.

FIG.1illustrates a vehicle utilizing the tandem position sensing system, according to some embodiments of the present disclosure.FIG.2is a perspective view of the a portion of the vehicle illustrating the sliding tandem and the tandem position sensing system, according to some embodiments of the present disclosure.FIG.3illustrates a block diagram of the tandem position sensing system, according to some embodiments of the present disclosure.

Referring toFIGS.1and2, the vehicle (e.g., the heavy duty vehicle)100includes a tow vehicle (e.g., a truck or tractor)102coupled to a trailer/chassis104, which has a sliding tandem106with a set of wheels that can slide along the length of the trailer/chassis104. In some embodiments, the tandem position sensing system200includes a radio frequency identification (RFID) reader210fixedly mounted to the sliding tandem106that can move forward and backward with respect to the trailer/chassis104along a first direction D1(e.g., the longitudinal direction of the trailer or the chassis), and further includes a plurality of RFID tags220fixedly connected to the underside (e.g., an undercarriage) of the trailer/chassis104at fixed positions (e.g., at predefined intervals). Each of the RFID tags220has a unique identifier that the RFID reader110may map to a particular location under the towed vehicle. The RFID reader210is configured to identify the unique identifier of one the plurality of RFID tags that is proximate to (e.g., closest to) the RFID reader210and to map the identifier to a particular position of the sliding tandem relative to the trailer/chassis104.

As illustrated inFIG.2, in some examples, the RFID tags220may be prepositioned on/within a tag platform202that is installed (e.g., fixedly coupled) at the bottom/underside of the trailer/chassis104. The RFID reader210may be positioned at the sliding tandem106in such a way that it is able to read the RFID tags220on the tag platform202. For example, at least an antenna of the RFID reader210may be attached to a cross-bar107of the sliding tandem106, which may extend in a second direction D1(that crosses the first direction D1), below the tag platform202, such that when the slider tandem106moves back and forth relative to the trailer/chassis104, the RFID tags220pass directly above the antenna of the RFID reader210. The remainder of the RFID reader electronics may be mounted in the same enclosure as, or in a separate enclosure from, the antenna element of the RFID reader210.

The tag platform202may be a long rail, channel (e.g., U-channel), strip, or the like, and may be made of any suitable non-conductive material such as plastic, fiberglass, and/or the like. The tag platform202may also be made of conductive material, such as metal, so long as a layer of non-conductive material is positioned between the conductive platform202and the RFID tags220. The tag platform202may be mounted to one or more frame cross members (e.g., cross bars or I-beams) at the undercarriage of the trailer/chassis104in any suitable manner. For example, the tag platform202may be attached to the trailer/chassis104by any suitable means, such as welding, fastening (e.g., via rivets/screws), adhering via an adhesive, and/or the like.

The position of the RFID reader110and the RFID tags220are not limited to that described above. For example, the strip of RFID tags220may be installed at the tandem106and may move forward and backwards with the tandem106, and the RFID reader210may be attached to a fixed position under the towed vehicle104in close proximity to the strip.

The position of the sliding tandem106relative to the trailer/chassis104may be locked by virtue of one or more pins105that pass through corresponding ones of the trailer/chassis holes104aand tandem holes106awhen correctly lined up. Thus, tandem locking positions may be defined as positions where the holes104aand106aline up (to allow passage of the one or more pins105). In some embodiments, at least one of the RFID tags220corresponds in position to each of the tandem locking positions. For example, when the tandem locking positions are spaced at regular intervals, at least some of the RFID tags220may be spaced at the same regular interval. In some embodiments, a separation between adjacent ones of the tandem locking positions is integer multiples (e.g., 1×, 2×, . . . ) of a separation between adjacent ones of the plurality of RFID tags220. For example, when the tandem locking positions are spaced at 4-inch intervals, the adjacent RFID tags220may be spaced apart by about 4 inches, 2 inches, or about 1 inch.

Referring toFIG.3, according to some embodiments, each RFID tag220includes a tag antenna222and an integrated circuit (IC; or RFID IC)224. The tag antenna222is configured to transmit and receive radio frequency (RF) signals. In some examples, the tag antenna222may activate the RFID IC224in response to receiving an RF signal. The RFID IC224stores the unique identifier of the RFID tag220(e.g., in an internal memory). When the RFID IC224receives RF energy from the tag antenna222, it modulates the RF energy with the unique identifier to generate a modulated RF signal for return transmission by the tag antenna222.

In some embodiments, the RFID reader210includes a reader antenna212, a processing circuit214, and a communication circuit216. The reader antenna212is configured to transmit and receive RF signals. The processing circuit214is configured to generate an RF signal for transmission by the reader antenna212, to receive a modulated RF signal from an RFID tag220that is proximate to (e.g., closest to) the RFID reader210via the reader antenna212, and to detect the unique identifier based on the modulated RF signal. The reader antenna212may transmit/receive at around 13.56 MHz, however, this is merely an example, and any suitable interrogation frequency may be employed. Further, width of the beam produced by the reader antenna212may depend on the separation between adjacent RFID tags220(e.g., narrower beam for shorter separation). Further, the transmit strength and receive sensitivity of the reader antenna212may depend on the vertical offset (e.g., along the third direction D3) between the reader antenna121and the RFID tags220, and other factors.

In some embodiments, the processing circuit214translates the unique RFID identifications from one or more nearby RFID tags220and their relative signal strengths into a sliding tandem position. As the slider tandem106moves relative to the trailer/chassis104, the RFID tags220will move relative to the RFID reader210. As an RFID tag220moves closer to the reader antenna212, its corresponding signal strength will grow until it reaches a maximum when the RFID tag220is directly above the reader antenna212(and the two RFID tags220are aligned in the vertical direction D3). This signal strength diminishes as the RFID tag220moves further away from the reader antenna212. By monitoring this signal strength, the RFID reader210can determine when it is aligned with a particular RFID tag220. However, embodiments of the present disclosure are not limited thereto. For example, the RFID reader210may merely identify an RFID tag220with the strongest signal strength and assume alignment with that RFID tag220.

In some embodiments, the RFID reader210(e.g., the processing circuit214) may then map the RFID tag identifier to a particular sliding tandem position. This mapping may be performed based on a lookup table stored in the memory of the processing circuit214that maps the individual unique identifiers of the tags to particular sliding tandem positions. However, embodiments of the present disclosure are not limited thereto. For example, the actual positions of the tandem holes106a(which may be expressed as sequential numeric values) may be programmed into the non-volatile memories of the respective RFID tags220, and may be read directly by the RFID reader220without the need for a lookup table.

When the reader antenna212is similarly distanced from two RFID tags220(e.g., is around the midpoint between adjacent tags220), the strengths of the return signals from the adjacent tags220may be similar. This can create a collision zone in which the reader210may not be able to accurately determine the location of the sliding tandem106. In such instances, the RFID reader210does not update/change its previous determination as to the sliding tandem position until the signal strength from one of the two adjacent tags220is maximized or greatly increased to the signal strength of the other.

The communication circuit216is configured to communicate the data generated by the processing circuit214to one or more external sources for compiling and/or further processing. This data may include, for example, the determined sliding tandem position and the unique identifier(s) of nearest RFID tag(s)220.

In some examples, the communication circuit216may communicate directly with a telematics gateway (e.g., a telematics gateway circuit)114, which may be at the nose box of the trailer/chassis104and have wireless communication capability, so the data from the processing circuit214may be transmitted via cellular or broadband (e.g., Wi-Fi) connection to an external server10(e.g., a remote server10on the cloud20) for monitoring and/or processing. The communication circuit216may transmit data to the telematics gateway114over a controller area network (CAN) bus of the trailer/chassis104, an RS232/485 connection, a power line communication (PLC) connection, a wireless communication link (e.g., Wi-Fi or Bluetooth) or any other connection via a suitable protocol.

In some examples, the external server10may transmit corresponding information to a data receiver116(e.g., a mobile tablet or phone, a display device, an autonomous truck controller, etc.) at the vehicle100(e.g., in the cab of tractor102) to allow a truck driver or autonomous system to make actionable decisions based on the position of the sliding tandem106. However, embodiments of the present disclosure are not limited thereto, and the communication circuit216may also communicate directly with the data receiver116via a wireless communication link (e.g., Wi-Fi or Bluetooth) or any other connection via a suitable protocol.

When the sliding tandem position is relayed to a driver or a dispatcher, this information may be instrumental in ensuring the proper functionality and safety of the sliding tandem106. In addition to alerting the driver of potentially critical safety concerns, the data gathered by the tandem position sensing system200may be incorporated into online or offline algorithms (that may be running on the remote server10or the data receiver116) to alert the driver when CSA violations are pending or changes in the turning radius of the vehicle are anticipated. In some examples, the remote server10or the data receiver116may monitor the location of the vehicle100and inform the driver of the need to adjust the sliding tandem position when the vehicle crosses a state border that necessitates the adjustment. Further, having knowledge of the sliding tandem position as the tandem is being repositioned, reduces the number of times that the driver needs to exit the truck cab to check the position, thus simplifying the tandem repositioning process.

In some embodiments, the RFID reader210is coupled to the electrical system of the trailer/chassis104and is electrically powered from the electrical circuit of the anti-lock braking system (ABS), the light circuit providing power to the lights of the trailer/chassis104, one or more solar panels on the roof of the trailer104or at the chassis, a power-over-ethernet (PoE) connection, wireless power transmission, and/or any other suitable source of power. For example, the RFID reader210may also include an internal battery (e.g., a rechargeable battery)218that can power operations of the RFID reader210.

As used herein, the term “processing circuit” includes any combination of hardware, firmware, and software, employed to process data or digital signals. Processing circuit hardware may include, for example, application specific integrated circuits (ASICs), general purpose or special purpose central processing units (CPUs), digital signal processors (DSPs), graphics processing units (GPUs), and programmable logic devices such as field programmable gate arrays (FPGAs). In a processing circuit, as used herein, each function is performed either by hardware configured, i.e., hard-wired, to perform that function, or by more general-purpose hardware, such as a CPU, configured to execute instructions stored in a non-transitory storage medium. A processing circuit may be fabricated on a single printed wiring board (PWB) or distributed over several interconnected PWBs. A processing circuit may contain other processing circuits; for example, a processing circuit may include two processing circuits, an FPGA and a CPU, interconnected on a PWB.

The tandem position sensing system200may be designed to be easily installed during trailer manufacture or a retrofit. Referring again toFIGS.1-2, the housing of the RFID reader210may have a visible indication (e.g., a notch, line, arrow, or the like) showing where the center of the reader antenna212is located, and the tag platform202may have visible indications showing where the center of each tag antenna222is located along with a sequential numeric indicator. In some examples, the RFID reader210may be attached to the frame of the sliding tandem106near the top of the tandem frame such that the antenna is pointing up and about 1 inch to about 2 inches below the lowest trailer frame cross members. The linear position of the installed tag platform202may be such that the RFID tag220corresponding to the actual tandem locking position is located directly above the reader antenna212. Here, there is no need to install the tag platform202such that the individual RFID tags220are precisely aligned with their respective sliding tandem holes106a(i.e., for each tandem locking position). A linear offset may exist to allow more convenient installation of the components if the correct RFID tag220is positioned over the reader antenna212for each tandem locking position.

In some examples, the reader antenna212may be a 65 mm square antenna or a 25 mm round antenna, and the tag platform202may be a 2 inch wide plastic or fiberglass strip with about a 2 inch or about a 4 inch tag separation; however, this is merely an example, and each of the tag platform202width and the tag separation may assume any suitable value. The total length of the tag platform202may be sufficient to cover all possible sliding tandem locations. For example, the tag platform202may be about 60 inches in length to accommodate 29 RFID tags220that may be arranged at 2 inch intervals. However, embodiments of the present disclosure are not limited thereto, and the tag platform202may be made up of multiple shorter sections (e.g., multiple channels/strips) for ease of installation and shipping.

In some examples, the tag platform202may be a channel (e.g., a U-channel) that is filled with a non-conductive encapsulant (e.g., epoxy) to seal the RFID tags220from exposure and prevent damage from environmental hazards (e.g., dirt, debris, water, etc.). Here, the wireless nature of the RFID reader interrogation makes the tandem position sensing system200less prone to environmental noise/obstruction/contamination.

As described above, the tandem position sensing system200is a low-cost solution for determining and reporting the position and state of the sliding tandem, which provides a number of desirable features absent from a trailer not equipped with a tandem position sensor. For example, the driver (or autonomous vehicle) can be alerted to the expected turning radius of the coupled trailer/chassis104. This information is desirable prior to entering inner cities or other places where tighter turning radiuses are expected or necessary. Further, the driver, dispatcher, or autonomous vehicle can be alerted to sliding tandem positions that violate local laws or ordinances before enforcement officers notice or have a chance to react to the infraction, thus avoiding fines, CSA violations, or the like. The sliding tandem position data can also be used to confirm whether or not the sliding tandem106has inadvertently moved during operation, indicating an unlocked tandem106, which can be a potentially critical safety concern. Furthermore, with tandem position reporting, the driver (or autonomous vehicle) can execute the tandem repositioning without visually checking/verifying the actual position of the sliding tandem (less trips between the cab and tandem leads to less time spent adjusting the sliding tandem and is safer for the driver). Additionally, the tandem position sensing system200can be installed during production of new trailers or may be easily retrofitted to existing fielded trailers without the need for complicated calibration. That is, the RFID reader210can be “calibrated” with a tape measure and proper placement of the strip relative to the RFID reader210, and doesn't necessary require communication with a computer.

As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. For example, the expression “A and/or B” denotes A, B, or A and B. Expressions such as “one or more of” and “at least one of,” when preceding a list of elements, modify the entire list of elements and do not modify the individual elements of the list. For example, the expression “one or more of A, B, and C,” “at least one of A, B, or C,” “at least one of A, B, and C,” and “at least one selected from the group consisting of A, B, and C” indicates only A, only B, only C, both A and B, both A and C, both B and C, or all of A, B, and C.

Further, the use of “may” when describing embodiments of the inventive concept refers to “one or more embodiments of the inventive concept.” Also, the term “exemplary” is intended to refer to an example or illustration.

It will be understood that when an element or layer is referred to as being “on”, “connected to”, “coupled to”, or “adjacent” another element or layer, it can be directly on, connected to, coupled to, or adjacent the other element or layer, or one or more intervening elements or layers may be present. When an element or layer is referred to as being “directly on,” “directly connected to”, “directly coupled to”, or “immediately adjacent” another element or layer, there are no intervening elements or layers present.