Patent Publication Number: US-2019170567-A1

Title: Methods and apparatus to detect load applied to a vehicle suspension

Description:
FIELD OF THE DISCLOSURE 
     This disclosure relates generally to detecting vehicle weight and, more particularly, to methods and apparatus to detect load applied to a vehicle suspension. 
     BACKGROUND 
     In recent years, determining a weight of a vehicle has become increasingly sophisticated. For example, some systems determine a weight of a vehicle based on a measured pressure applied to a suspension. In some examples, vehicle suspension systems include load sensing devices that measure pressure. 
     SUMMARY 
     An example apparatus includes a vehicle spring positioned between a first spring seat and a second spring seat. A cap is coupled to the first spring seat to define a cavity. A force sensor is positioned in the cavity adjacent a surface of the first spring seat. 
     An example apparatus including a spring seat, means for biasing, and a force sensor positioned between the spring seat and the means for biasing. 
     An example apparatus including means for biasing positioned between a first spring seat and a second spring seat. A cap coupled to the first spring seat to define a cavity. An isolator positioned in the cavity. The example apparatus also includes means for sensing a force positioned in the cavity adjacent a surface of the first spring seat. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  illustrates an example vehicle in which the teachings of this disclosure may be implemented. 
         FIG. 2  illustrates an example suspension constructed in accordance with the teachings of this disclosure that may be used to implement the example vehicle of  FIG. 1 . 
         FIG. 3  is a partially exploded view of the example suspension of  FIG. 2 . 
         FIGS. 4A and 4B  illustrate an example sensor of the example suspension of  FIGS. 2 and 3 . 
         FIG. 5  illustrates another example suspension that may be used to implement the example vehicle of  FIG. 1 . 
         FIG. 6  is a partially exploded view of the example suspension of  FIG. 5 . 
         FIGS. 7A and 7B  illustrate an example sensor of the example suspension of  FIGS. 5 and 6 . 
         FIG. 8  is an example method for positioning a sensor on the example vehicle suspension of  FIGS. 2 and 3 . 
         FIG. 9  is an example method for positioning a sensor on the example vehicle suspension of  FIGS. 5 and 6 . 
     
    
    
     The figures are not to scale. Wherever possible, the same reference numbers will be used throughout the drawing(s) and accompanying written description to refer to the same or like parts. 
     DETAILED DESCRIPTION 
     Some known vehicles employ measuring apparatus to detect or measure a vehicle weight. Some known example vehicles employ sensors that are integrated with a vehicle suspension. Integrating a sensor with a suspension system is beneficial because a total weight of the vehicle is sensed through the suspension. 
     Some known vehicle suspensions employ measuring apparatus that measure a pressure applied to an airbag suspension system to determine vehicle weight. Some known vehicle suspension systems include loading apparatus that bend or deflect (e.g., relative to a flat or initial position) to measure a bending force to detect or measure vehicle weight. As a result of the size and/or packaging constraints of such loading apparatus, in some instances, significant modification of preexisting suspension geometries may be needed to avoid changing (e.g., raising) a vehicle ride height and/or handling characteristic of a vehicle. In some cases, modifications necessary to implement such loading apparatus can double the number of suspension components, increasing manufacturing costs. 
     Examples disclosed herein provide an efficient, low-profile solution to determine vehicle weight across multiple platforms without the need to design different suspension architectures. Example suspensions disclosed herein employ a force sensor (e.g., a thin-film transducer) to sense an applied force to the vehicle suspensions. For example, when a load is applied to the suspensions, example sensors disclosed herein produce an electrical signal (e.g., a voltage, a change in resistance, a change in capacitance, etc.) based on amount of force or pressure applied to the suspensions and/or the sensors. Some example sensors disclosed herein may be formed from Quantum Tunneling Composites (e.g., composite materials of metals, non-conducting elastomeric binders, etc.) that allow for the production of thin sensors. 
     Additionally, example sensors disclosed herein may have different configurations to accommodate different types of vehicle suspensions (e.g., a MacPherson strut, a leaf spring suspension, etc.). For example, example sensors disclosed herein may have a rectangular shape, a circular shape, and/or any other shape. In some instances, a shape or profile of an example sensor disclosed herein may improve sensing accuracy. 
     Some example sensors disclosed herein may be isolated between a first side by a spring seat (e.g., that provides natural resistance to shock and environmental conditions) and a second side of the spring seat by a rubber isolator. Isolation of the sensor enables the sensor to more accurately sense a weight of a vehicle. As such, the example sensors disclosed herein improve electronic stability control, accuracy in driveline calibration, algorithms based on vehicle weight distribution, autonomous vehicle systems, and information provided to a driver to reduce unbalanced driving. Some example sensors disclosed herein may be printed or formed directly onto a spring seat or an upper strut surface of a suspension. For example, sensors disclosed herein may be printed onto the spring seat using heat molding manufacturing processes or techniques. Printing an example sensor directly onto a suspension component reduces part count. 
     The teachings of this disclosure may be implemented with any type of suspension (e.g., a steerable suspension, a non-steerable suspension, a MacPherson strut, a Short Long Arms suspension) for use with any types of vehicles. 
       FIG. 1  illustrates an example vehicle  100  in which the teachings of this disclosure may be implemented. In the illustrated example, the vehicle  100  includes front wheels  102 ,  104  supported by a front suspension and rear wheels  106 ,  108  supported by a rear suspension. The vehicle  100  (e.g., the front and rear suspensions) of the illustrated example includes a control system  110  to measure total vehicle weight information to improve ride and/or handling characteristics. For example, the control system  110  may determine an uneven load in a bed  112  of the vehicle  100 . 
       FIG. 2  illustrates an example suspension  200  of the vehicle  100  of  FIG. 1 . For example, the suspension  200  of the illustrated example may support the front driver-side wheel  102  ( FIG. 1 ). The front passenger-side wheel  104  may be supported by a similar (e.g., identical) suspension ( FIG. 1 ). 
     The suspension  200  of the illustrated example is an example coil-spring suspension (e.g., a MacPherson strut). The suspension  200  of the illustrated example includes a shock absorber  202 . The shock absorber  202  includes a first end  204  (e.g., a piston end) coupled to a frame  206  of the vehicle  100  adjacent the wheel  102  and a second end  208  (e.g., a housing) coupled to a suspension control link  210  of the suspension  200 . 
     During operation, the suspension  200  (e.g., the shock absorber  202 ) of the illustrated example controls unwanted motion of the vehicle  100  by reducing a magnitude of vibratory motion. The example suspension  200  of the illustrated example gradually dissipates forces generated when the wheel (e.g., the wheel  102 ) traverses a bump, pothole, and or other road surface anomalies in a controlled manner that helps a driver maintain control over the vehicle  100  and/or provide the driver with a comfortable driving environment. 
     Additionally, the suspension  200  of the illustrated example measures a load applied to the suspension  200 . For example, the shock absorber  202  of the illustrated example measures and/or detects a first load or force  212  applied in a direction between the first end  204  and the second end  208  (e.g., along a longitudinal axis) of the shock absorber  202 . For example, the shock absorber  202  of the illustrated example receives the force  212  applied to the shock absorber  202  in a direction parallel to the longitudinal axis of the shock absorber  202 . When the vehicle  100  receives a load, the shock absorber  202  of the illustrated example absorbs (e.g., damps) and/or dissipates forces and the associated energy to reduce discomfort of a driver of the vehicle  100 . 
       FIG. 3  is a partially exploded view of the example suspension  200  of  FIG. 2 . The shock absorber  202  of the illustrated example includes a housing  300  and a piston rod  302  movable relative to the housing  300 . The illustrated example of  FIG. 3  also includes means for biasing. In the illustrated example, the means for biasing is a spring  304 . The spring  304  of the illustrated example is positioned between a first spring seat  306  formed adjacent an end of the housing  300  and a second spring seat  308  spaced from the first spring seat  306 . The first spring seat  306  of the illustrated example includes a body  310  having a first surface  312  to engage or receive an end of the spring  304  and a second surface  314  opposite the first surface  312 . The body  310  of the illustrated example includes a spring guide  316  (e.g., a first tube) protruding from the first surface  312  to guide the end of the spring  304  and a first boss  318  protruding from the second surface  314  to guide the piston rod  302 . The body  310  of the illustrated example includes an opening  320  (e.g., a through hole) to slidably receive an end of the piston rod  302 . 
     To cover or protect the piston rod  302  from damage and/or debris, the suspension  200  of the illustrated example includes a cap  322 . The cap  322  of the illustrated example couples to the body  310  of the first spring seat  306 . The cap  322  of the illustrated example includes an annular wall  324  (e.g., a circumferential wall) to define a cavity  326 . The cap  322  of the illustrated example includes a second boss  328  positioned in the cavity  326  and having an opening  330  to receive the piston rod  302 . 
     To measure a load (e.g. the force  212  of  FIG. 2 ) applied to the vehicle  100 , the suspension  200  of the illustrated example includes means for sensing a force. In the illustrated example, the means for sensing a force is a sensor (e.g., a force sensor)  332 . The sensor  332  of the illustrated example is positioned on the second surface  314  of the first spring seat  306 . The sensor  332  includes an opening  334  (e.g., a central hole) to receive the first boss  318  of the first spring seat  306 . In some examples, the first boss  318  has a diameter that is substantially similar (e.g., slightly smaller than) a diameter of the opening  334  such that the first boss  318  prevents the sensor  332  from shifting or moving radially relative to a longitudinal axis of the shock absorber  202 . Alternatively, in some examples, the sensor  332  may be printed onto the second surface  314  of the first spring seat  306  to reduce parts count. 
     To mitigate the sensor  332  from moving or displacing relative to the second surface  314 , the suspension  200  of the illustrated example includes an isolator  336  (e.g., a rubber isolator). The isolator  336  includes an opening  338  (e.g., a central hole) to receive the piston rod  302  and an annular flange  340  defining a cavity  342  to receive the sensor  332 . In some examples, the suspension  200  may not include the isolator  336 . 
     To assemble the suspension  200 , the sensor  332  is positioned on the second surface  314  of the first spring seat  306 . The first boss  318  of the illustrated example may guide placement of the sensor  332  on the first spring seat  306 . The isolator  336  is positioned on the sensor  332  and the cap  322  is coupled to the first spring seat  306 . The cap  322  and the first spring seat  306  of the illustrated example define a cavity  344  to receive the isolator  336  and the sensor  332  when the cap  322  is coupled to the first spring seat  306 . Additionally, the second boss  328  of the cap  322  of the illustrated example is adjacent (e.g., enjoins or couples to) the first boss  318  of the first spring seat  306  to provide a support or guide for the piston rod  302 . The cap  322  and the first spring seat  306  of the illustrated example form or provide a tight seal to prevent debris or contaminates from entering the cavity  344  and/or the sensor  332 . The sensor  332  of the illustrated example does not deflect to sense a load. Additionally, the isolator  336  and the sensor  332  of the illustrated example are relatively thin (e.g., 1 millimeter, 2 millimeters, 3 millimeters, etc.) so that a ride height of the vehicle  100  is not meaningfully altered (e.g., increased or decreased), and the components of the suspension  200  do not need to be modified. Thus, the sensor  332  provides a relatively low profile that does not require modification of the shock absorber  202  such that the example sensor  332  may be implemented with an existing shock absorber (e.g., an off-the-shelf shock absorber) and the sensor  332  will not meaningfully affect or vary (e.g., increase or decrease) a ride height of a vehicle. 
     During operation, a load provided to the wheel  102  imparts a load on the suspension  200 . The sensor  332  of the illustrated example senses the load and produces (e.g., outputs) an electrical signal that corresponds to a magnitude of the load. The control system  110  ( FIG. 1 ) may employ the output of the sensor  332  to adjust one or more parameters of the vehicle  100  to improve ride handling characteristics. In some examples, a user may employ the sensor  332  of the suspension  200  determine if a load carried by the vehicle  100  is too large. For example, a load provided or carried by the bed  112  ( FIG. 1 ) of the vehicle  100  may be sensed by the sensor  332  of the suspension  200 . The electrical signal may be sent to the control system  110  of the vehicle  100  to determine if the load is within an acceptable range, for example. If the load is not within an acceptable range, the control system  110  may provide an alert (e.g., a light on the dashboard, an audible noise, etc.) so the user of the vehicle  100  may address the issue. In some examples, the examples disclosed herein may be used to determine if a load is evenly distributed in the vehicle  100 . For example, output signals from sensors (e.g., the sensor  332 ) positioned at each of the four wheels  102 - 108  ( FIG. 1 ) may employed to determine if a load of the vehicle is (e.g., evenly) distributed. For example, if the output signals from sensors (e.g., the sensor  332 ) of the front wheels  102  and  104  are greater than a threshold, and output signals from sensors of the rear wheels  106  and  108  are less than a threshold, the control system  110  may warn the driver of the vehicle  100  to shift a load in the bed  112  of the vehicle  100  in  FIG. 1  more towards a rear of the vehicle  100  so that the load is more evenly distributed. 
     To correlate outputs (e.g., electrical signals) of the sensor  332  to loads, the sensor  332  of the illustrated example is calibrated prior to installation on the suspension  200 . For example, various known loads are applied to the sensor  332  (e.g., during a bench test). The resulting electrical signals produced by the sensor  332  are measured and a calibration curve is produced, indicating the correspondence between the applied load and the produced electrical signal. It is beneficial to calibrate the sensor  332  because some sensors are prone to calibration shift over time when the load distribution is not even (e.g., the resistive material migrates through the substrates to less-loaded areas). However, the disclosed configuration helps mitigate calibration shift because the sensor  332  is enclosed by the isolator  336 , the first spring seat  306  and/or the first boss  318 , which helps distribute the load and capture the entire load through the load path of the vehicle suspension  200 . 
       FIG. 4A  is a top view of the example sensor  332  of  FIG. 3 .  FIG. 4B  is a side view of the example sensor  332  of  FIGS. 3 and 4A . Referring to  FIGS. 4A and 4B , the example sensor  332  includes leads  402  to communicatively couple the sensor  332  to the control system  110  of the vehicle  100 . For example, the leads  402  may receive a voltage from the Engine Control Unit (ECU) to enable the sensor  332  to produce an electrical signal (e.g., a varying voltage) for sensing a load. In some examples, the leads  402  may receive a voltage and the sensor  332  may measure a change in resistance to detect an applied force. In the illustrated example, the sensor  332  is circular in shape. However, in some examples, the sensor  332  may have a square shape, a rectangular shape, and/or another shape. In the illustrated example of  FIG. 4A , the sensor  332  has a first radius  404  and a second radius  406 . The first radius  404  and the second radius  406  affect the output produced by the sensor  332  based on the material properties of the sensor  332 . Additionally, the first radius  404  and the second radius  406  may be modified in any way so the sensor  332  may be positioned in and/or on a particular component or components of a suspension system. Also, to determine the expected output, the sensor  332  is provided a voltage and various known loads. The resulting outputs are correlated to the provided voltage and applied loads to produce a calibration curve. 
     The sensor  332  of the illustrated example may include one or more traces (e.g., electrical traces) to sense a force applied to the sensor  332 . In some examples, the sensor  332  can detect a force without bending. In other words, the sensor  332  remains substantially flat (e.g., remains within 10% deflection from a plane of the thickness  408 ) when a force is applied to the sensor. 
     To manufacture the sensor  332  of the illustrated example, measurements are taken of the suspension component that is to house the sensor  332 . For example, the sensor  332  is formed such that the first radius  404  and the second radius  406  are substantially similar (e.g., slightly smaller than) the second surface  314  of the first spring seat  306  and the diameter of the first boss  318 . The sensor  332  of the illustrated example may be formed from Quantum Tunneling Composites, piezoelectric materials, piezo resistive materials, etc., that allow for the production of thin sensors. For example, the sensor  332  may be formed from a piezoelectric film pressed between two electrodes (e.g., copper) surrounded by a protective coating (e.g., polyethylene). In some examples, the sensor  332  may be a thin film transducer. In some examples, the sensor  332  may be printed onto the second surface  314  of the first spring seat  306  using, for example, heat molding manufacturing processes or techniques. 
       FIG. 4B  illustrates a side view of the example sensor  332 . The example sensor  332  may be manufactured to have a thickness  408  within a certain range. For example, the sensor  332  may have a thickness  408  of approximately between 1 millimeter and 6 millimeters. Manufacturing the sensor  332  to have a thickness within this range may improve results and/or will not meaningfully affect the ride height of the vehicle. In some examples, the sensor  332  may be manufactured to have a thickness outside of the above-noted range. For example, the sensor  332  may be manufactured to have a thickness less than 1 millimeter. 
       FIG. 5  illustrates another example suspension  500  that may be used to implement the example vehicle  100  of  FIG. 1 . For example, the suspension  500  of the illustrated example may support the rear wheels  106  and  108  of the vehicle  100  of  FIG. 1 . The example suspension  500  of the illustrated example is an example leaf-spring suspension. The suspension  500  of the illustrated example includes means for biasing. In the illustrated example, the means for biasing is a biasing element  502 . The biasing element  502  is coupled to an axle  504  of the vehicle  100 . In the illustrated example, the biasing element  502  is a leaf spring that extends perpendicular relative to the axle  504  of the vehicle  100 . The axle  504  of the illustrated example includes a spring seat  506  to receive the biasing element  502  and a bracket  508  and U-bolts  512 ,  514  to couple the biasing element  502  to the axle  504 . 
     During operation, the biasing element  502  deflects in response to forces generated when the wheels  106 ,  108  ( FIG. 1 ) traverse a bump, pothole, and/or other road surface anomaly. In the illustrated example, a shock absorber  516  absorbs (e.g., damps) and/or dissipates forces and the associated energy in a controlled manner to mitigate driver discomfort. Additionally, the suspension  500  of the illustrated example measures a load applied to the suspension  500 . For example, the biasing element  502  of the illustrated example measures and/or detects a first load or force  510  applied at a deflection point of the biasing element  502 . 
       FIG. 6  is a partially exploded view of the example suspension  500  of  FIG. 5  including the biasing element  502 , the axle  504 , the spring seat  506 , and the bracket  508 . The biasing element  502  of the illustrated example includes leaves  602  (e.g., metal strips) coupled to one another. In the illustrated example, the leaves  602  are coupled by a clip  604  (e.g., a rebound clip) that prevents the leaves  602  from fanning out. In the illustrated example, the leaves  602  include openings  606  (e.g., through holes) to receive fasteners  608  to couple the leaves  602  to one another. The spring seat  506  of the illustrated example includes a first surface  610  to support or engage the biasing element  502 . 
     To couple the biasing element  502  to the spring seat  506 , the suspension  500  includes the bracket  508 . The bracket  508  of the illustrated example includes a first portion  614  and a second portion  616  removably coupled to the first portion  614 . The first portion  614  of the illustrated example includes apertures  618  to receive the second portion  616 . In the illustrated example, the first portion  614  includes a recessed area  620  to engage the axle  504 . The second portion  616  of the illustrated example includes the fasteners  608  and a plate  622 . The plate  622  of the illustrated example includes a top bracket  624  to couple the U-bolts  512 ,  514  to the plate  622 . The top bracket  624  of the illustrated example includes a tongue  628  and a recess  630  to receive the U-bolt  514 . For example, to receive the U-bolt  514 , the tongue  628  is elevated and the U-bolt  514  is placed in the recess  630 . The tongue  628  is lowered to secure the U-bolt  514  in the recess  630 . 
     To measure a load applied to the vehicle  100 , the suspension  500  of the illustrated example includes a sensor (e.g., a force sensor)  632 . The sensor  632  of the illustrated example is positioned on the first surface  610  of the spring seat  506 . In the illustrated example, the sensor  632  includes openings  634  to receive the fasteners  608  to enable the fasteners  608  to engage or couple to the spring seat  506 . In some examples, the sensor  632  does not include the openings  634  when the fasteners  608  do not engage or couple to the spring seat  506 . Alternatively, in some examples, the sensor  632  may be printed onto the first surface  610  of the spring seat  506  to reduce parts count. 
     To assemble the suspension  500 , the sensor  632  is positioned on the first surface  610  of the spring seat  506 . The biasing element  502  is positioned on the sensor  632  and the bracket  508  couples the biasing element  502  to the spring seat  506 . In the illustrated example, the sensor  632  is thin (e.g., 1 millimeter, 2 millimeters, 3 millimeters, etc.) so that the ride height of the vehicle  100  is not meaningfully changed, and the components of the suspension  500  do not need to be modified in any way. The sensor  632  functions or operates substantially similar to the sensor  332  of the example suspension  200  of  FIGS. 2-3, 4A and 4B . 
       FIG. 7A  is a top view of the example sensor  632  of  FIG. 6 .  FIG. 7B  is a side view of the example sensor  632  of  FIGS. 6 and 7A . Referring to  FIGS. 7A and 7B , the example sensor  632  of the illustrated example includes leads  700  to communicatively couple the sensor  632  to the control system  110  of the vehicle  100 . For example, the leads  700  may receive a voltage from the ECU to enable the sensor  632  to produce an electrical signal (e.g., a varying voltage) for determining a detected load. In some examples, the leads  700  may receive a voltage and the sensor  632  may measure a change in resistance to detect an applied force. In the illustrated example, the sensor  632  is rectangular in shape. However, in some examples, the sensor  632  may have a square shape, a circular shape, and/or another shape. In the illustrated example, the sensor  632  includes the openings  634  to receive the fasteners  608 . The openings  634  of the illustrated example may be sized to fit any suspension component. In some examples, the sensor  632  may not include the openings  634 . In some examples, the sensor  632  may be the sensor  332  of  FIGS. 2-3, 4A and 4B . 
       FIG. 7B  illustrates a side view of the example sensor  632 . The example sensor  632  may be manufactured to have a thickness  702  within a certain range. For example, the sensor  632  of the illustrated example may have a thickness  702  approximately between 1 millimeter and 6 millimeters. Manufacturing the sensor  632  to have a thickness within this range may improve results and/or does not meaningfully affect the ride height of the vehicle. In some examples, the sensor  632  may be manufactured to have a thickness outside of the above-noted range. For example, the sensor  632  may be manufactured to have a thickness less than 1 millimeter. 
     To manufacture the sensor  632  of the illustrated example, measurements are taken of the suspension component that will house the sensor  632 . For example, the example sensor  632  is formed to be substantially similar (e.g., slightly smaller than) the first surface  610  of the spring seat  506 . The sensor  632  of the illustrated example may be formed from Quantum Tunneling Composites, piezoelectric materials, piezo resistive materials, etc., that allow for the production of thin sensors. For example, the example sensor  632  may be formed from a piezoelectric film pressed between two electrodes (e.g., copper) surrounded by a protective coating (e.g., polyethylene). In some examples, the example sensor  632  may be printed onto the first surface  610  of the spring seat  506  using, for example, heat molding manufacturing processes or techniques. 
       FIG. 8  is an example method  800  of assembling the example vehicle suspension  200  of  FIGS. 2 and 3 .  FIG. 9  is an example method  900  of assembling the example vehicle suspension  500  of  FIGS. 5 and 6 . While an example manner of assembling the suspensions  200  and  500  are illustrated in  FIGS. 8 and 9 , one or more of the steps and/or processes illustrated in  FIGS. 8 and 9  may be combined, divided, re-arranged, omitted, eliminated and/or implemented in any other way. Further still, the example methods of  FIGS. 8 and 9  may include one or more processes and/or steps in addition to, or instead of, those illustrated in  FIGS. 8 and 9 , and/or may include more than one of any or all of the illustrated processes and/or steps. Further, although the example methods are described with reference to the flowcharts illustrated in  FIGS. 8 and 9 , many other methods of assembling the suspensions  200  and  500  of  FIGS. 2-3 and 5-6  may alternatively be used. 
     The example method  800  begins when the sensor  332  is positioned on a surface of the first spring seat  306  (block  802 ). For example, positioning the sensor  332  on the surface  314  of the first spring seat  306 . The isolator  336  is positioned on the sensor  332  (block  804 ). The cap  322  is then coupled to the spring seat  306  (block  806 ). 
     Referring to  FIG. 9 , the sensor  632  is positioned on the spring seat  506  between the spring seat  506  (block  902 ). The biasing element  502  is positioned (e.g., directly) on the sensor  632  (block  904 ). For example, the sensor  632  is positioned between the spring seat  506  and the biasing element  502 . The bracket  508  couples the biasing element  502 , the spring seat  506  and the sensor  632  to the axle  504 . 
     From the foregoing, it will be appreciated that example methods, apparatus and articles of manufacture have been disclosed that enable an efficient, low-profile solution to measure vehicle weight across multiple platforms without the need to design for multiple suspension architectures. The examples disclosed are beneficial because these examples utilize thin sensors that can be implemented with (e.g., installed in) existing suspensions requiring minimal change to manufacturing and assembly of the suspensions. Additionally, the sensors disclosed herein are relatively thin and may increase a ride height by less than one millimeter. The examples disclosed are capable of being used across multiple platforms of the vehicle other than suspensions. For example, under a bed of a vehicle. The disclosed examples increase resistance to environmental factors (e.g., temperature, humidity, shock) and these examples are cost and weight efficient. In addition, the disclosed examples improve electronic stability control, accuracy in driveline calibration, algorithms based on vehicle weight distribution, autonomous vehicle systems, and information provided to driver to reduce unbalanced driving. 
     Although certain example methods, apparatus and articles of manufacture have been disclosed herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the claims of this patent.