Pressure sensing of a cylinder actuator using a position sensor

Abstract

An example system includes: a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides the cylinder to a first actuator chamber and a second actuator chamber; an auxiliary cylinder having a sensing piston that is movable within the auxiliary cylinder, wherein the sensing piston divides the auxiliary cylinder into a fluid sensing chamber that is fluidly coupled to the first actuator chamber, and a gas chamber having precharged gas; a position sensor that provides sensor information indicating a position of the sensing piston within the auxiliary cylinder; and a controller performing operations comprising determining, based on the sensor information indicating the position of the sensing piston, a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

Description

Pressure Sensing of an Actuator Using a Position SensorCROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Provisional Patent Application No.63 / 751,328, filed January 30, 2025, the entire contents of which are incorporated herein by reference.FIELD OF THE INVENTION

[0002] The present disclosure relates generally to fluid power systems and, more particularly, to systems and methods for determining pressure in an actuator using position sensing rather than direct pressure measurement.BACKGROUND

[0003] Control of a hydraulic or pneumatic cylinder actuator may involve controlling forces applied with a piston of the cylinder actuator with high precision. It may thus be desirable to obtain information indicating forces or pressures in the cylinder actuator, and such information can then be used by a controller to control operation of the cylinder actuator.

[0004] Using direct pressure sensors has several drawbacks. Pressure sensors add more complexity to a fluid system as they may require additional parts. Also, a pressure sensor taps into the fluid, creating an additional leak path and failure point. Existing pressure sensors can leak over time and have a limited operational lifespan. Further, if the pressure sensor needs to be replaced, the system may leak fluid to the environment, which is not desirable.

[0005] In some applications, force sensors (e.g., load cells) may be used. There are several types of such force sensors such as Wheatstone bridge circuits, strain gauge load cells, S-beamload cells (also called tension load cells), compression load cells, canister load cells, pneumatic load cells, and single-point load cells.

[0006] Regardless of the type of force sensor, they also have drawbacks. Similar to pressure sensors, force sensors add more complexity to the fluid system as they may require additional parts. It may also be difficult to find an effective location to place the force sensor in the cylinder actuator, without reducing overall reliability of the fluid system.

[0007] It may thus be desirable to measure forces or pressures in an actuator cylinder without using pressure sensors or force sensors / load cells. Particularly, it may be desirable to have a sensing configuration that does not involve physically tapping into the fluid, thus eliminating the failure point from a pressure sensor. It may also be desirable for the sensing configuration to avoid having to mount force sensors / load cells that add complexity to the system.

[0008] It is with respect to these and other considerations that the disclosure made herein is presented.SUMMARY

[0009] The present disclosure describes implementations that relate to pressure sensing of an actuator using a position sensor.

[0010] In a first example implementation, the present disclosure describes systems for pressure sensing of an actuator using a position sensor. An example system includes: a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides an internal space of the cylinder to a first actuator chamber and a second actuator chamber; an auxiliary cylinder having a sensing piston that is movable within the auxiliary cylinder, wherein the sensing piston divides a respective internal space of theauxiliary cylinder into a fluid sensing chamber and a gas chamber, wherein the fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the gas chamber includes gas that is precharged to a particular pressure level; a position sensor that provides sensor information indicating a position of the sensing piston within the auxiliary cylinder; and a controller performing operations comprising determining, based on the sensor information indicating the position of the sensing piston, a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

[0011] In a second example implementation, the present disclosure also describes a method of operating the system of the first example implementation.

[0012] In a third example implementation, the present disclosure further describes assemblies related to the system of the first example implementation and the method of the second example implementation.

[0013] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, implementations, and features described above, further aspects, implementations, and features will become apparent by reference to the figures and the following detailed description.BRIEF DESCRIPTION OF THE FIGURES

[0014] The novel features believed characteristic of the illustrative examples are set forth in the appended claims. The illustrative examples, however, as well as a preferred mode of use, further objectives and descriptions thereof, will best be understood by reference to thefollowing detailed description of an illustrative example of the present disclosure when read in conjunction with the accompanying Figures.

[0015] Figure 1 illustrates a block diagram of a system having a pressure sensing configuration based on position sensing, according to an example implementation.

[0016] Figure 2 illustrates a system having a double-acting cylinder actuator and a pressure sensing configuration based on position sensing, according to an example implementation.

[0017] Figure 3 illustrates a system having a single-acting cylinder actuator and a pressure sensing configuration based on position sensing, according to an example implementation.

[0018] Figure 4A is a graph showing correlation between position of a sensing piston and a pressure level of fluid in a first actuator chamber of a cylinder actuator, according to an example implementation.

[0019] Figure 4B is a graph showing correlation betw een pressure level of fluid in the first actuator chamber and a voltage signal generated by a position sensor, according to an example implementation.

[0020] Figure 5 is a block diagram of a controller, according to an example implementation.

[0021] Figure 6 is a flow chart of a method for determining pressure in a cylinder actuator using position sensing, according to an example implementation.

[0022] Figure 7 is a flowchart of a method for determining pressure based on gas volume calculations, according to an example implementation.

[0023] Figure 8 is a flowchart of a method for controlling a cylinder actuator using pressure sensing and valve control, according to an example implementation.

[0024] Figure 9 is a flowchart of a method for using a transfer function or lookup table to correlate sensing piston position to pressure level, according to an example implementation.DETAILED DESCRIPTION

[0025] Within examples, disclosed herein are systems, methods, and assemblies relating to using position sensing to infer pressure in an actuator chamber of an actuator. In an example implementation, a system includes an auxiliary sensing container such as an auxiliary cylinder. The system may also have a movable member such as a sensing piston that is movable in the auxiliary cylinder. The sensing piston divides the auxiliary cylinder into a gas chamber and a fluid sensing chamber. The fluid sensing chamber is fluidly coupled to the actuator chamber of the cylinder actuator, while the gas chamber has a gas that is precharged to a particular pressure. The position of the sensing piston is detected by a position sensor, and the position information is used to infer the pressure level of fluid in the actuator chamber of the cylinder actuator.

[0026] Figure 1 illustrates a block diagram of a system 10 having a pressure sensing configuration based on position sensing, according to an example implementation. The system 10 includes a source 12 of fluid that supplies fluid. The source 12 of fluid may be a pump or other fluid supply mechanism (e.g.. an accumulator or other portion of a hydraulic system, etc.). A fluid reservoir 14 is provided for storing fluid and receiving fluid discharged from other components of the system 10.

[0027] A valve assembly 16 is positioned to control fluid flow within the system 10. The valve assembly 16 may regulate the direction and rate of fluid flow to and from an actuator 18. The actuator 18 may be a cylinder actuator as described in Figures 2 and 3 or may be a motor (e.g., hydraulic motor), and may be coupled to an implement 20. The implement 20 mayrepresent any type of load or equipment that the actuator 18 operates, such as ground engaging equipment or other machinery components.

[0028] The system 10 includes one or more sensing containers for pressure sensing based on position detection. In the example shown, the system 10 includes a first sensing container 22 with an associated first position sensor 23. In examples, the system 10 may include other sensing containers and sensors such as second sensing container 24 with an associated second position sensor 25, and a third sensing container 26 with an associated third position sensor 27.

[0029] Each sensing container 22, 24, 26 may be used to target, or may be tuned for, a particular range of pressure where precise control may be desired. Particularly, each sensing container may have a gas chamber with gas precharged to a particular pressure level that is suitable for a particular range of pressure of fluid in the actuator 18.

[0030] For example, one sensing container may be used to sense pressure in the range between 0-500 pounds per square inch (psi), another sensing container may be used to sense pressure in the range between 1000 psi and 2000 psi, and so on. As such, the use of multiple sensing containers 22, 24, 26 may allow for pressure sensing across different pressure ranges, with each sensing container having gas precharged to a different pressure level.

[0031] Each position sensor 23, 25, 27 may detect the position of a movable member (such as a sensing piston) within the respective sensing container. The position sensors 23, 25, 27 are communicatively coupled to a controller 28. The controller 28 receives sensor information from the position sensors 23, 25, 27 and processes this information to determine pressure levels in the actuator 18. The controller 28 may also be communicatively coupled to the source 12 of fluid and the valve assembly 16 to control fluid flow based on the determined pressure levels, and particularly to control the force applied by the implement 20 coupled to the actuator 18.

[0032] Having described the general system architecture and components in Figure 1, the following sections provide example implementations. Particularly, Figures 2-3 illustrate specific configurations of cylinder actuators with integrated pressure sensing systems based on position detection. These implementations demonstrate how the components described in the block diagram of Figure 1 may be arranged and interconnected in practical applications, including both double-acting and single-acting cylinder configurations, as examples.

[0033] Figure 2 illustrates a system 100 having a cylinder actuator 101 and a pressure sensing configuration based on position sensing, according to an example implementation. The system 100 is an example implementation of the system 10 of Figure 1.

[0034] The cylinder actuator 101 has a cylinder 102 and an actuator piston 104 that is slidably accommodated (axially movable) in the cylinder 102. The actuator piston 104 is configured to move in a linear direction (e.g., up and down in Figure 2) in the cylinder 102.

[0035] The actuator piston 104 includes a piston head 106 and a rod 108 extending from the piston head 106 along a central longitudinal axis direction of the cylinder 102. The rod 108 can be coupled to a load that represents, for example, an implement (e.g., the implement 20) of a machine and any forces applied thereto.

[0036] The piston head 106 divides the internal space of the cylinder 102 into a first actuator chamber 110 and a second actuator chamber 112. The first actuator chamber 110 can be referred to as head-side chamber as the fluid therein interacts with the piston head 106, and the second actuator chamber 112 can be referred to as rod-side chamber as the rod 108 is disposed partially therein.

[0037] If fluid (e.g., hydraulic fluid or gas / air) is provided from the source 12 of fluid (e.g., a pump) through the valve assembly 16 then via fluid line 114 to the first actuator chamber 110, the actuator piston 104 may extend (e.g., move downward in Figure 2), while fluid isdischarged from the second actuator chamber 112 via fluid line 116 and the valve assembly 16 to the fluid reservoir 14. Conversely, if fluid is provided from the source 12 of fluid through the valve assembly 16 then via the fluid line 116 to the second actuator chamber 112, the actuator piston 104 may retract (e.g., move upward in Figure 2), while fluid is discharged from the first actuator chamber 110 via the fluid line 114 and the valve assembly 16 to the fluid reservoir 14. As mentioned above with respect to Figure 1, the valve assembly 16 may control fluid flow between the source 12 of fluid, the cylinder actuator 101, and the fluid reservoir 14.

[0038] In many applications, it may be desirable to determine the force that the actuator piston 104 (and the implement attached hereto) applies or is subjected to. This may allow the controller 28 of the cylinder actuator 101 to control fluid flow and pressure level to apply a specific force via the actuator piston 104, for example.

[0039] Using a pressure sensor, force sensor, or load cell may complicate the system, increase cost, and reduce reliability. As such, the system 100 includes a sensing configuration that involves determining position of a movable member and infer pressure level of fluid in the first actuator chamber 110 based on the determined position.

[0040] Particularly, the system 100 includes an auxiliary container or auxiliary cylinder 118 having a sensing movable member such as sensing piston 120 that is linear / axially movable therein. The auxiliary cylinder 118 represents any of the sensing containers 22, 24, 26 of Figure 1 and can take any form or shape (e.g., can be a body of a valve, a body of a piston or bladder accumulator, etc.). The sensing piston 120 can be any type of a movable member (e.g., a poppet, a spool, a compressible member such as a bladder, etc.).

[0041] The sensing piston 120 divides the internal space of the auxiliary7cylinder 118 into a fluid sensing chamber 122 and a gas chamber 124. The fluid sensing chamber 122 is fluidly coupled via fluid line 126 to the first actuator chamber 110 of the cylinder actuator 101. On theother hand, the gas chamber 124 is filled with gas 128 that is precharged to a predetermined pressure.

[0042] As the fluid sensing chamber 122 is fluidly coupled to the first actuator chamber 1 10, pressure level of fluid in the fluid sensing chamber 122 is substantially the same as pressure level of fluid in the first actuator chamber 110. Thus, determining pressure level of fluid in the fluid sensing chamber 122 amounts to determining pressure level of fluid in the first actuator chamber 110.

[0043] As fluid is provided to or is withdrawn from the fluid sensing chamber 122, the sensing piston 120 responsively moves because of the gas 128 in the gas chamber 124. Particularly, if fluid is provided to the fluid sensing chamber 122, the fluid sensing chamber 122 expands and the sensing piston 120 moves (e.g., downward in Figure 2), compressing the gas 128. Conversely, if fluid is withdrawn from the fluid sensing chamber 122 (as fluid is discharged from the first actuator chamber 110), the sensing piston 120 moves (e.g., upward in Figure 2) as the gas 128 (w hich is pressurized) expands, thus increasing the volume of the gas chamber 124 and contracting the fluid sensing chamber 122.

[0044] The auxiliary cylinder 118 includes a position sensing configuration to determine the position of the sensing piston 120, thus facilitating inference of pressure level of fluid in the fluid sensing chamber 122. For example, the position sensing configuration includes one or more magnets attached to the sensing piston 120. For instance, the position sensing configuration may include a magnet 130 attached to or embedded in the sensing piston 120 as shown in Figure 2.

[0045] Further, the position sensing configuration may include one or more position sensors mounted externally to the auxiliary cylinder 118. If more than one sensor are used, they could be spaced apart along a length of the auxiliary cylinder 118.

[0046] In the example implementation of Figure 2, one position sensor 132 (e g., a magnetic sensor) is shown. However, it should be understood that more than one sensor could be used depending on a stroke or range of movement of the sensing piston 120.

[0047] Tn an example, the position sensor 132 may be an anisotropic magnetoresistive (AMR) sensor. An AMR sensor may be made up of a thin film of alloy on a glass or silicon board. Such AMR sensor measures the position of the sensing piston 120 by interacting with the magnet 130 and measuring the angle of a magnetic field by detecting changes in an electrical resistance of the alloy material.

[0048] Particularly, such AMR sensor may operate by interacting with the magnet 130 where the magnet 130 generates an external magnetic field that is applied in a direction perpendicular to the axial direction of the auxiliary cylinder 118 or the sensing piston 120. The electric resistance value of the alloy material of the AMR sensor changes according to the magnetic field strength or intensity. AMR sensors utilize this effect to determine the position of the sensing piston 120.

[0049] Notably and advantageously, if the position sensing configuration uses multiple AMR sensors distributed along a length of the auxiliary cylinder 118, the range of movement or stroke of the sensing piston 120 is divided into a set of ranges, and each sensor of the sensors is configured to detect position of the sensing piston 120 in a particular respective range of the set of ranges. This may enhance position sensing accuracy. Also, using multiple sensors may facilitate cancelling atmospheric or environmental magnetic noise.

[0050] Other types of magnetic sensors could be used. For example, another type of magnetic sensor can detect changes in magnetic flux as the magnet 130 moves with the sensing piston 120. The position of the magnet 130 and the sensing piston 120 may then be determined based on such changes in the magnetic flux.

[0051] For example, the position sensor 132 may be a magnetostrictive position sensor. A magnetostrictive position sensor may include a waveguide and the magnet 130 attached to the sensing piston 120. The sensor may generate an interrogation pulse that travels along the waveguide. When the interrogation pulse interacts with the magnetic field from the magnet 130, a strain pulse may be generated that travels back to the sensor. By measuring the time between the interrogation pulse and the return strain pulse, the position of the sensing piston 120 may be determined.

[0052] In some examples, the position sensor 132 may be a Hall effect sensor. A Hall effect sensor may detect the position of the sensing piston 120 by measuring the voltage difference (Hall voltage) across an electrical conductor when a magnetic field is applied perpendicular to the cunent flow. As the magnet 130 moves with the sensing piston 120, the Hall effect sensor may detect changes in the magnetic field strength and direction, thereby determining the position of the sensing piston 120.

[0053] In other examples, the position sensor 132 may be a giant magnetoresistance (GMR) sensor. A GMR sensor may use the giant magnetoresistance effect, where the electrical resistance of thin layers of ferromagnetic and non-magnetic materials changes significantly in response to an applied magnetic field. As the magnet 130 moves with the sensing piston 120, the GMR sensor may detect variations in the magnetic field, allowing for determination of the position of the sensing piston 120.

[0054] In further examples, the position sensor 132 may be a tunnel magnetoresistance (TMR) sensor. A TMR sensor may operate based on the quantum mechanical tunneling effect, where electrons tunnel through a thin insulating barrier between two ferromagnetic layers. The tunneling current may be highly sensitive to the relative orientation of the magnetization in the ferromagnetic layers, which changes in response to an external magnetic field from the magnet130. This may allow the TMR sensor to detect the position of the sensing piston 120 with high sensitivity7.

[0055] In additional examples, the position sensor 132 may be a magnetoinductive sensor. A magnetoinductive sensor may include one or more coils that generate an alternating magnetic field. When the magnet 130 moves with the sensing piston 120, the magnetic field from the magnet 130 may interact with the alternating magnetic field generated by the coils, inducing changes in the impedance or inductance of the coils. These changes may be measured to determine the position of the sensing piston 120.

[0056] In some examples, the position sensor 132 may be a Wiegand sensor. A Wiegand sensor may utilize a Wiegand wire, which is a specially processed ferromagnetic wire that exhibits a rapid change in magnetization when exposed to a changing external magnetic field. As the magnet 130 moves with the sensing piston 120, the Wiegand wire may generate voltage pulses that can be counted or timed to determine the position of the sensing piston 120.

[0057] Also, although a magnetic sensing configuration is shown, any other type of position sensor can be used. For instance, a Linear Variable Differential Transformer (LVDT), which is a device that converts an object’s linear motion into an electrical signal, can be used.

[0058] In other examples, the position sensor 132 may be a capacitive displacement sensor. A capacitive displacement sensor may measure changes in capacitance between the sensor and a target surface on the sensing piston 120. As the sensing piston 120 moves within the auxiliary cylinder 118, the distance between the sensor and the target surface changes, resulting in a corresponding change in capacitance that can be measured to determine the position of the sensing piston 120.

[0059] In some examples, the position sensor 132 may be an inductive proximity sensor. An inductive proximity7sensor may generate an electromagnetic field and detect changes in thefield caused by the presence or movement of a conductive target attached to or forming part of the sensing piston 120. As the sensing piston 120 moves, the sensor may detect variations in the electromagnetic field, allowing for determination of the position of the sensing piston 120.

[0060] Tn further examples, the position sensor 132 may be an optical position sensor. An optical position sensor may use light-based detection methods, such as laser triangulation, time-of-flight measurement, or optical encoders. The sensor may emit light toward the sensing piston 120 or a reflective surface attached thereto, and measure reflected light or changes in light patterns to determine the position of the sensing piston 120 within the auxiliary cylinder 118.

[0061] In additional examples, the position sensor 132 may be an ultrasonic position sensor. An ultrasonic position sensor may emit ultrasonic sound waves toward the sensing piston 120 and measure the time required for the sound waves to reflect back to the sensor. By calculating the time-of-flight of the ultrasonic waves, the sensor may determine the distance to the sensing piston 120, thereby determining its position within the auxiliary' cylinder 118.

[0062] In some implementations, the position sensor 132 may be a potentiometric position sensor. A potentiometric position sensor may include a resistive element and a wiper that moves with the sensing piston 120. As the sensing piston 120 moves, the wiper may slide along the resistive element, changing the electrical resistance between the wiper and one or more terminals. This change in resistance may be measured and correlated to the position of the sensing piston 120.

[0063] Regardless of whether one or multiple sensors are used, and the ty pe of sensor, the one or more sensors may generate sensor information, e g., a voltage signal, a digital signal, or a message, that is indicative of the position of the sensing piston 120.

[0064] Although the auxiliary' cylinder 118 is shown in an orientation that is parallel to, and schematically separate from, the cylinder actuator 101, other configurations arecontemplated. For example, the auxiliary cylinder 118 can be integrated into a shared single housing with the cylinder 102. Particularly, while the auxiliary cylinder 118 can be separated from the cylinder actuator 101 and connected thereto via the fluid line 126 (e.g., a hose, pipe, or tube), in other example implementations, it can be integrated in a single housing with the cylinder actuator 101 such that the fluid line 126 is a passage drilled in such housing to connect the first actuator chamber 110 to the auxiliary cylinder 118.

[0065] Further, although the auxiliary cylinder 118 is shown to be parallel to the cylinder actuator 101, in other example implementation, the axis of travel of the sensing piston 120 of the auxiliary cylinder 118 may be co-linear, co-planar, or disposed in any other orientation relative to the cylinder actuator 101.

[0066] Also, the cylinder actuator 101 is shown as a double-acting cylinder (where fluid is used to move the actuator piston 104 in both directions) in Figure 2. In other examples, a single-acting cylinder could be used.

[0067] Figure 3 illustrates a system 200 having a cylinder actuator 202 and a pressure sensing configuration based on position sensing, according to an example implementation. The system 200 has several components of the system 100, and such components are referred to using the same reference numbers.

[0068] The system 200 differs from the system 100 in that the system 200 includes a cylinder actuator 202 that is single-acting. Particularly, rather than retracting the actuator piston 104 via fluid provided to the second actuator chamber 112, the cylinder actuator 202 includes a spring 204 that can bias the actuator piston 104 and cause it to retract as fluid is discharged from the first actuator chamber 110.

[0069] Tn other example implementation, a different type of actuator can be used. For example, a motor (e.g., a hydraulic motor) rather than a cylinder actuator can be used. Suchmotor may have a rotating member and tw o chambers similar to the chambers of the cylinder actuator 101, 202. In this case, the disclosed system may be used to determine or infer a rotary position of the rotating member of such motor using pressure information.

[0070] Regardless of the type of actuator (e.g., single-acting cylinder, double-acting, or motor), by detecting the position of the sensing piston 120, the pressure level of fluid in the fluid sensing chamber 122, and thus in the first actuator chamber 110, can be inferred. Particularly, the position of the sensing piston 120 is correlated with the pressure level in the fluid sensing chamber 122.

[0071] For example, the ideal gas law- can be used to determine pressure level in the gas chamber 124 based on the volume of the gas chamber 124 (which is based on the position of the sensing piston 120). By determining pressure of gas in the gas chamber 124, the pressure level of fluid in the fluid sensing chamber is 122 is also determined.

[0072] Particularly, the ideal gas law7, also called the general gas equation, can be expressed as:PV = nRTwhere P is the pressure of the gas 128. V is the volume of the gas chamber 124, n is the amount of gas, R is the ideal gas constant, and T is the temperature of the gas 128. Thus, for a given temperature, the term nRT can be considered as a constant. The position of the sensing piston 120 determines the volume V of the gas chamber 124, and thus the pressure level in the gas chamber 124 can be determined from the equation above.

[0073] By determining the pressure of the gas 128, the pressure of fluid in the fluid sensing chamber 122 is also determined. For example, once the sensing piston 120 reaches an equilibrium position, the pressure of fluid in the fluid sensing chamber 122 is equal to the gas pressure in the gas chamber 124. As such, the position of the sensing piston 120 is used todetermine or infer pressure level of fluid in the fluid sensing chamber 122, and thus in the first actuator chamber 110.

[0074] The precharge pressure level to which the gas 128 is pressurized may depend on a particular range of pressure of fluid in the first actuator chamber 110 where precise control may be desired. For example, if the desired pressure control range of fluid is between 1000 psi and 2000 psi, it may be desirable to have the gas precharge level as 1000 psi. If a lower precharge pressure level (e.g., 100 psi) is used, the sensing piston 120 may substantially reach its bottommost position before pressure level of fluid in the fluid sensing chamber 122 reaches 1000 psi. Thus, the range of motion of the sensing piston 120 as fluid pressure changes between 1000 psi and 2000 psi would be minimal, thus reducing the resolution of position sensing generally.

[0075] In some examples, multiple control ranges may be desired. For example, it may be desirable to have precise pressure or force control around 500 psi and also around 2000 psi. In these examples, multiple auxiliary cylinders similar to the auxiliary cylinder 118 may be used, where each auxiliary cylinder has gas precharged at a respective pressure level that corresponds to a desired fluid pressure control range. This is represented in Figure 1 where the system 100 includes multiple sensing containers 22, 24, 26 that can be used to target multiple control ranges.

[0076] Figure 4A is a graph 300 showing correlation between position of the sensing piston 120 and the pressure level of fluid in the first actuator chamber 110, according to an example implementation. In the graph 300, the x-axis represents position of the sensing piston 120 in inches, the lefty-axis represents hydraulic pressure of fluid in the fluid sensing chamber 122 (and thus in the first actuator chamber 110) in psi. and the right y-axis represents the voltage generated by the position sensor 132 in Volts. Line 302 is a plot of the voltage signal generated by the position sensor 132 based on the position of the sensing piston 120, and line304 is a plot of the pressure level in the fluid sensing chamber 122 based on the position of the sensing piston 120 (or the voltage generated by the position sensor 132).

[0077] In this example, a desired fluid pressure control range in the first actuator chamber 110 may be between 1000 and 3000 psi, which is varied by any type of pressure control system or pressure control valve. The position sensor 132 has a measurement range of 6 inches and generates an output voltage signal between 0 Volts (when the sensing piston 120 is at 0 inch position) and 5 Volts (when the sensing piston 120 is at 6 inch position). Also, in this example, the sensing piston 120 has a diameter of 1.5 inch and has an allowable stroke of 6 inch with the gas 128 having a precharge of 1000 psi.

[0078] When hydraulic fluid is initially provided to the first actuator chamber 110 and the fluid sensing chamber 122, the sensing piston 120 does not move until the pressure level of fluid exceeds the precharge pressure (1000 psi) as shown in Fig. 3 A. Whenever pressure level is under 1000 psi, the sensing piston 120 is considered to be in a fully -retracted initial position at 0 inch, and the position sensor 132 generates 0 Volts.

[0079] As hydraulic pressure level increases as indicated by the line 304, the sensing piston 120 begins to move and the position sensor 132 generates a signal of an increasing voltage as indicated by the line 302. At 3000 psi hydraulic pressure, the sensing piston 120 is at 4 inches of travel within the auxiliary cylinder 118 and a voltage output signal of 3.33V is generated by the position sensor 132.

[0080] A transfer function that relates the voltage output of the position sensor 132 to the hydraulic pressure in the fluid sensing chamber 122 (and thus in the first actuator chamber 110) can therefore be created as shown in Figure 4B.

[0081] Figure 4B is a graph 400 showing correlation between the pressure level of fluid in the first actuator chamber 110 and the voltage signal generated by the position sensor 132,according to an example implementation. In the graph 400, the x-axis represents the voltage signal generated by the position sensor 132, and the y-axis represents hydraulic pressure of fluid in the fluid sensing chamber 122 (and thus in the first actuator chamber 110) in psi. Line 402 is a plot of the relationship between the voltage generated by the position sensor 132 and pressure level of fluid in the fluid sensing chamber 122. Thus, the pressure level of the fluid sensing chamber 122 (and in the first actuator chamber 110) is inferred from the position signal generated by the position sensor 132.

[0082] Thus, in operation, the controller 28 may receive the sensor information from the position sensor 132 indicating the position of the sensing piston 120 within the auxiliary cylinder 118. Based on this position information, the controller 28 may determine the volume of the gas chamber 124. Using the ideal gas law and the known precharge pressure of the gas 128, the controller 28 may calculate the current pressure in the gas chamber 124. Since the sensing piston 120 reaches an equilibrium position where the pressure of fluid in the fluid sensing chamber 122 equals the gas pressure in the gas chamber 124. the controller 28 may thereby determine the pressure level of fluid in the fluid sensing chamber 122. Because the fluid sensing chamber 122 is fluidly coupled to the first actuator chamber 110 via the fluid line 126, the determined pressure level in the fluid sensing chamber 122 corresponds to the pressure level in the first actuator chamber 110.

[0083] In some implementations, the controller 28 may use a transfer function or lookup table that correlates the position of the sensing piston 120 (or the voltage signal from the position sensor 132) directly to the pressure level in the first actuator chamber 110, as illustrated in Figures 4A and 4B. This may allow for rapid determination of pressure without requiring real-time calculation of gas volumes and pressures. The controller 28 may use the determined pressure information to control operation of the valve assembly 16, thereby regulating fluid flow to the cylinder actuator 101 or 202 to achieve desired force or pressure levels.

[0084] An analog voltage signal output is used herein as an example for illustration. The output of the position sensor 132 can take other output format such as a message on a Communication Area Network (CAN) bus, or other forms of digital output.

[0085] Figure 5 illustrates a block diagram of the controller 28, according to an example implementation. The controller 28 may include one or more processors 500, a communication interface 502, data storage 504, and an output interface 510, all of which may be communicatively linked together by a bus 506.

[0086] The processor(s) 500 may include one or more general-purpose processors and / or one or more special-purpose processors. The processor(s) 500 may be configured to execute computer-readable program instructions such as executable instructions 508 that are stored in the data storage 504 and are executable to provide the functionality' of the controller 28 described herein.

[0087] The communication interface 502 may' allow the controller 28 to communicate with other components of the system, such as the position sensor 132 (or the position sensors 23, 25, 27 in the system 10 of Figure 1) and also communicate with the source 12 of fluid and the valve assembly 16. The communication interface 502 may be configured to receive sensor information from the position sensor 132 indicating the position of the sensing piston 120. The communication interface 502 may support wired or wireless communication protocols, and may facilitate data exchange between the controller 28 and various sensors, actuators, and other control elements within the system.

[0088] The data storage 504 may include one or more non-transitory computer-readable storage media that may be read or accessed by the processor(s) 500. The data storage 504 may include volatile and / or non-volatile storage components, such as optical, magnetic, organic or other memory' or disc storage, which may be integrated in whole or in part with the processor(s)500. The data storage 504 may contain the executable instructions 508 that, when executed by the processor(s) 500, cause the controller 28 to perform various operations described herein, such as determining pressure levels based on position sensor information, calculating gas volumes and pressures using the ideal gas law7, and controlling the valve assembly 16 to regulate fluid flow7.

[0089] The output interface 510 may allow the controller 28 to send control signals to other components of the system. For example, the output interface 510 may be configured to send control signals to the valve assembly 16 to regulate fluid flow to the cylinder actuator 101 or 202. The output interface 510 may also provide signals to other system components, such as displays, indicators, or additional control systems that may be part of a larger machine or equipment assembly.

[0090] The bus 506 may provide a communication link between the various components of the controller 28, allowing data and control signals to be exchanged between the processor(s) 500, the communication interface 502, the data storage 504, and the output interface 510. The bus 506 may be implemented using various architectures and protocols suitable for interconnecting electronic components w ithin a computing device.

[0091] Figure 6 is a flow-chart of a method 600 for determining pressure in a cylinder actuator using position sensing, according to an example implementation. The method 600 begins at step 602, which involves providing a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides an internal space of the cylinder to a first actuator chamber and a second actuator chamber.

[0092] At step 604, the method 600 involves providing an auxiliary cylinder having a sensing piston that is movable within the auxiliary cylinder, wherein the sensing piston divides a respective internal space of the auxiliary7cylinder into a fluid sensing chamber and a gaschamber, wherein the fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the gas chamber includes gas that is precharged to a particular pressure level.

[0093] At step 606, the method 600 includes receiving (at the controller 28) sensor information from a position sensor, the sensor information being indicative of a position of the sensing piston within the auxiliary cylinder. The method 600 then proceeds to step 608, which involves determining (by the controller 28), based on the sensor information, a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

[0094] Figure 7 is a flowchart of a method 700 for determining pressure based on gas volume calculations, according to an example implementation. The method 700 can be implemented by the controller 28, for example.

[0095] The method 700 begins at step 702, which involves receiving sensor information indicating the position of a sensing piston within an auxiliary cylinder. At step 704, the method 700 includes determining a volume of a gas chamber based on the position of the sensing piston. The method 700 then proceeds to step 706, which involves calculating gas pressure in the gas chamber using the ideal gas law based on the determined volume and a particular precharge pressure level.

[0096] At step 708, the method 700 includes determining a pressure level of fluid in a fluid sensing chamber based on the calculated gas pressure, wherein the pressure level of fluid in the fluid sensing chamber corresponds to a pressure level of fluid in a first actuator chamber that is fluidly coupled to the fluid sensing chamber.

[0097] Figure 8 is a flowchart of a method 800 for controlling a cylinder actuator using pressure sensing and valve control, according to an example implementation. The method 800 can be implemented by the controller 28, for example.

[0098] The method 800 begins at step 802, which involves determining a pressure level of fluid in a first actuator chamber using position sensing of a sensing piston in an auxiliary cylinder. At step 804, the method 800 includes controlling a valve assembly to regulate fluid flow to the first actuator chamber based on the determined pressure level of fluid in the first actuator chamber.

[0099] The method 800 then proceeds to step 806, which involves adjusting force applied by an actuator piston by controlling fluid flow through the valve assembly. At step 808, the method 800 includes monitoring the position sensor for feedback control to continue adjusting the force applied by the actuator piston based on updated pressure determinations.

[0100] Figure 9 is a flowchart of a method 900 for using a transfer function or lookup table to correlate sensing piston position to pressure level, according to an example implementation. The method 900 can be implemented by the controller 28, for example.

[0101] The method 900 begins at step 902, which involves receiving position information of a sensing piston from a position sensor. At step 904, the method 900 includes accessing a transfer function or lookup table that correlates sensing piston position to pressure level in a first actuator chamber. The method 900 then proceeds to step 906, which involves applying the transfer function or lookup table to correlate the position of the sensing piston to the pressure level in the first actuator chamber. At step 908, the method 900 includes outputting the determined pressure level for system control, wherein the determined pressure level may be used to control force applied by an actuator piston or to regulate fluid flow through a valve assembly.

[0102] The disclosed systems and methods provide several advantages over conventional pressure sensing approaches. By using position sensing to infer pressure levels in a cylinder actuator, the need for direct pressure sensors that tap into the fluid is eliminated, therebyremoving potential leak paths and failure points. This may enhance system reliability- and reduce maintenance requirements, as pressure sensors can leak over time and have limited operational lifespans.

[0103] Additionally, the disclosed approach avoids the complexity and installation challenges associated with force sensors or load cells, which may be difficult to position effectively within a cylinder actuator without compromising system reliability. The use of an auxiliary container / cy Under with a sensing piston / movable member and precharged gas chamber provides a non-intrusive method for pressure determination that does not require physical contact with the fluid in the actuator chamber.

[0104] In implementations using multiple auxiliary cylinders with different precharge pressures, the system may achieve high-resolution pressure sensing across multiple pressure ranges, allowing for precise control in various operating conditions. The position sensing configuration may utilize readily available sensor technologies such as magnetic sensors, which can be mounted externally to the auxiliary cylinder, further simplifying installation and maintenance. The controller may employ transfer functions or lookup tables to rapidly correlate position information to pressure levels, enabling real-time control of fluid flow and force application without requiring complex real-time calculations.

[0105] The detailed description above describes various features and operations of the disclosed systems with reference to the accompanying figures. The illustrative implementations described herein are not meant to be limiting. Certain aspects of the disclosed systems can be arranged and combined in a wide variety of different configurations, all of which are contemplated herein.

[0106] Further, unless context suggests otherwise, the features illustrated in each of the figures may be used in combination with one another. Thus, the figures should be generallyviewed as component aspects of one or more overall implementations, with the understanding that not all illustrated features are necessary for each implementation.

[0107] Additionally, any enumeration of elements, blocks, or steps in this specification or the claims is for purposes of clarity. Thus, such enumeration should not be interpreted to require or imply that these elements, blocks, or steps adhere to a particular arrangement or are carried out in a particular order.

[0108] Further, devices or systems may be used or configured to perform operations presented in the figures. In some instances, components of the devices and / or systems may be configured to perform the operations such that the components are actually configured and structured (with hardware and / or software) to enable such performance. In other examples, components of the devices and / or systems may be arranged to be adapted to, capable of, or suited for performing the operations, such as when operated in a specific manner.

[0109] By the term ‘'substantially” it is meant that the recited characteristic, parameter, or value need not be achieved exactly, but that deviations or variations, including for example, tolerances, measurement error, measurement accuracy limitations and other factors known to those with skill in the art, may occur in amounts that do not preclude the effect the characteristic was intended to provide.

[0110] The arrangements described herein are for purposes of example only. As such, those skilled in the art will appreciate that other arrangements and other elements (e.g., machines, interfaces, operations, orders, and groupings of operations, etc.) can be used instead, and some elements may be omitted altogether according to the desired results. Further, many of the elements that are described are functional entities that may be implemented as discrete or distributed components or in conjunction with other components, in any suitable combination and location.

[0111] While various aspects and implementations have been disclosed herein, other aspects and implementations will be apparent to those skilled in the art. The various aspects and implementations disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope being indicated by the following claims, along with the full scope of equivalents to which such claims are entitled. Also, the terminology used herein is for the purpose of describing particular implementations only, and is not intended to be limiting.

[0112] Embodiments of the present disclosure can thus relate to one of the enumerated example embodiments (EEEs) listed below.

[0113] EEE 1. A system comprising: a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides an internal space of the cylinder to a first actuator chamber and a second actuator chamber; an auxiliary cylinder having a sensing piston that is movable within the auxiliary cylinder, wherein the sensing piston divides a respective internal space of the auxiliary cylinder into a fluid sensing chamber and a gas chamber, wherein the fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the gas chamber includes gas that is precharged to a particular pressure level; a position sensor that provides sensor information indicative of a position of the sensing piston within the auxiliary' cylinder; and a controller performing operations comprising: receiving the sensor information indicating the position of the sensing piston, and determining a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

[0114] EEE 2. The system of EEE 1. further comprising: a magnet that is coupled to the sensing piston, wherein the position sensor comprises one or more sensors mounted externally to the auxiliary cylinder and configured to detect a respective position of the magnet.

[0115] EEE 3. The system of EEE 2, wherein each sensor of the one or more sensors is an anisotropic magnetoresistive sensor.

[0116] EEE 4. The system of EEE 2, wherein the magnet is embedded in the sensing piston.

[0117] EEE 5. The system of any of EEEs 1-4, wherein the cylinder actuator is a doubleacting cylinder or a single-acting cylinder.

[0118] EEE 6. The system of any of EEEs 1-5, wherein the controller performs further operations comprising: determining a volume of the gas chamber based on the sensor information indicating the position of the sensing piston; and determining gas pressure in the gas chamber based on the volume, wherein determining the pressure level of fluid in the fluid sensing chamber is based on the gas pressure.

[0119] EEE 7. The system of any of EEEs 1-6, wherein the auxiliary’ cylinder is a first auxiliary cylinder, and wherein the system further comprises: a second auxiliary cylinder having a respective sensing piston, a respective fluid sensing chamber, and a respective gas chamber, wherein the respective fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the respective gas chamber includes gas that is precharged to a respective pressure level that is different from the particular pressure level of the gas in the gas chamber of the first auxiliary cylinder.

[0120] EEE 8. The system of any of EEEs 1-7, wherein the position sensor is a magnetostrictive position sensor, a Hall effect sensor, a giant magnetoresistance sensor, a tunnel magnetoresistance sensor, a magnetoinductive sensor, a Wiegand sensor, a Linear Variable Differential Transformer, a capacitive displacement sensor, an inductive proximity sensor, an optical position sensor, an ultrasonic position sensor, or a potentiometric position sensor.

[0121] EEE 9. The system of any of EEEs 1-8, further comprising: a valve assembly configured to control fluid flow to the first actuator chamber, wherein the controller is communicatively coupled to the valve assembly and configured to control the valve assembly based on the pressure level of fluid in the first actuator chamber.

[0122] EEE 10. The system of any of EEEs 1-9, wherein the auxiliary cylinder is integrated into a shared housing with the cylinder actuator.

[0123] EEE 11. A method of determining pressure in a cylinder actuator of the system of any of EEEs 1-10. The method comprises: providing a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides an internal space of the cylinder to a first actuator chamber and a second actuator chamber; providing an auxiliary cylinder having a sensing piston that is movable within the auxiliary cylinder, wherein the sensing piston divides a respective internal space of the auxiliary cylinder into a fluid sensing chamber and a gas chamber, wherein the fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the gas chamber includes gas that is precharged to a particular pressure level; receiving sensor information from a position sensor, the sensor information indicative of a position of the sensing piston wi thin the auxiliary cylinder; and determining, based on the sensor information, a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

[0124] EEE 12. The method of EEE 11, wherein determining the pressure level of fluid in the fluid sensing chamber comprises: determining a volume of the gas chamber based on the position of the sensing piston; and calculating gas pressure in the gas chamber based on the volume and the particular pressure level.

[0125] EEE 13. The method of EEE 11 or EEE 12, further comprising: controlling a valve assembly to regulate fluid flow to the first actuator chamber based on the pressure level of fluid in the first actuator chamber.

[0126] EEE 14. The method of any of EEEs 11-13, wherein the position sensor comprises a magnet coupled to the sensing piston and one or more magnetic sensors mounted externally to the auxiliary cylinder.

[0127] EEE 15. The method of any of EEEs 11-14, further comprising: using a transfer function or lookup table to correlate the position of the sensing piston to the pressure level in the first actuator chamber.

[0128] EEE 16. A system comprising: a source of fluid; an actuator fluidly coupled to the source of fluid; one or more sensing containers, each sensing container having a movable member that divides an internal space of the sensing container into a fluid sensing chamber and a gas chamber, wherein each fluid sensing chamber is fluidly coupled to the actuator, and wherein each gas chamber includes gas that is precharged to a respective pressure level; one or more position sensors, each position sensor providing sensor information indicative of a position of a respective movable member within a respective sensing container; and a controller configured to receive the sensor information from the one or more position sensors and determine pressure levels of fluid in the respective fluid sensing chambers based on respective positions of respective movable members of the one or more sensing containers.

[0129] EEE 17. The system of EEE 16, further comprising: a valve assembly positioned to control fluid flow between the source of fluid and the actuator, wherein the controller is communicatively coupled to the valve assembly .

[0130] EEE 18. The system of EEE 16 or EEE 17, wherein each sensing container of the one or more sensing containers is tuned for a particular range of pressure where precise control is desired.

[0131] EEE 19. The system of any of EEEs 16-18, wherein gas in the respective gas chambers of the one or more sensing containers is precharged to different pressure levels to enable pressure sensing across different pressure ranges.

[0132] EEE 20. The system of any of EEEs 16-19, further comprising: an implement coupled to the actuator, wherein the controller is configured to control force applied by the implement based on the determined pressure levels.

Claims

CLAIMSWhat is claimed is:

1. A system comprising:a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides an internal space of the cylinder to a first actuator chamber and a second actuator chamber;an auxiliary cylinder having a sensing piston that is movable within the auxiliary cylinder, wherein the sensing piston divides a respective internal space of the auxiliary cylinder into a fluid sensing chamber and a gas chamber, wherein the fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the gas chamber includes gas that is precharged to a particular pressure level;a position sensor that provides sensor information indicative of a position of the sensing piston within the auxiliary cylinder; anda controller performing operations comprising:receiving the sensor information indicating the position of the sensing piston, anddetermining a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

2. The system of claim 1, further comprising:a magnet that is coupled to the sensing piston, wherein the position sensor comprises one or more sensors mounted externally to the auxiliary cylinder and configured to detect a respective position of the magnet.

3. The system of claim 2, wherein each sensor of the one or more sensors is an anisotropic magnetoresistive sensor.

4. The system of claim 2, wherein the magnet is embedded in the sensing piston.

5. The system of claim 1 , wherein the cylinder actuator is a double-acting cylinder or a single-acting cylinder.

6. The system of claim 1, wherein the controller performs further operations comprising:determining a volume of the gas chamber based on the sensor information indicating the position of the sensing piston; anddetermining gas pressure in the gas chamber based on the volume, wherein determining the pressure level of fluid in the fluid sensing chamber is based on the gas pressure.

7. The system of claim 1, wherein the auxiliary cylinder is a first auxiliary cylinder, and wherein the system further comprises:a second auxiliary cylinder having a respective sensing piston, a respective fluid sensing chamber, and a respective gas chamber, wherein the respective fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the respective gas chamber includes gas that is precharged to a respective pressure level that is different from the particular pressure level of the gas in the gas chamber of the first auxiliary cylinder.

8. The system of claim 1, wherein the position sensor is a magnetostrictive position sensor, a Hall effect sensor, a giant magnetoresistance sensor, a tunnelmagnetoresistance sensor, a magnetoinductive sensor, a Wiegand sensor, a Linear Variable Differential Transformer, a capacitive displacement sensor, an inductive proximity sensor, an optical position sensor, an ultrasonic position sensor, or a potentiometric position sensor.

9. The system of claim 1, further comprising:a valve assembly configured to control fluid flow to the first actuator chamber, wherein the controller is communicatively coupled to the valve assembly and configured to control the valve assembly based on the pressure level of fluid in the first actuator chamber.

10. The system of claim 1 , wherein the auxiliary cylinder is integrated into a shared housing with the cylinder actuator.

11. A method of determining pressure in a cylinder actuator, the method comprising:providing a cylinder actuator having a cylinder and an actuator piston that is movable within the cylinder, wherein the actuator piston divides an internal space of the cylinder to a first actuator chamber and a second actuator chamber;providing an auxiliary cylinder having a sensing piston that is movable within the auxiliary7cylinder, wherein the sensing piston divides a respective internal space of the auxiliary' cylinder into a fluid sensing chamber and a gas chamber, wherein the fluid sensing chamber is fluidly coupled to the first actuator chamber, and wherein the gas chamber includes gas that is precharged to a particular pressure level;receiving sensor information from a position sensor, the sensor information indicative of a position of the sensing piston w ithin the auxiliary' cylinder; anddetermining, based on the sensor information, a pressure level of fluid in the fluid sensing chamber, thereby determining a respective pressure level of fluid in the first actuator chamber.

12. The method of claim 11, wherein determining the pressure level of fluid in the fluid sensing chamber comprises:determining a volume of the gas chamber based on the position of the sensing piston; andcalculating gas pressure in the gas chamber based on the volume and the particular pressure level.

13. The method of claim 11, further comprising:controlling a valve assembly to regulate fluid flow to the first actuator chamber based on the pressure level of fluid in the first actuator chamber.

14. The method of claim 11, wherein the position sensor comprises a magnet coupled to the sensing piston and one or more magnetic sensors mounted externally to the auxiliary cylinder.

15. The method of claim 11, further comprising:using a transfer function or lookup table to correlate the position of the sensing piston to the pressure level in the first actuator chamber.

16. A system comprising:a source of fluid;an actuator fluidly coupled to the source of fluid;one or more sensing containers, each sensing container having a movable member that divides an internal space of the sensing container into a fluid sensing chamber and a gas chamber, wherein each fluid sensing chamber is fluidly coupled to the actuator, and wherein each gas chamber includes gas that is precharged to a respective pressure level;one or more position sensors, each position sensor providing sensor information indicative of a position of a respective movable member within a respective sensing container; anda controller configured to receive the sensor information from the one or more position sensors and determine pressure levels of fluid in the respective fluid sensing chambers based on respective positions of respective movable members of the one or more sensing containers.

17. The system of claim 16, further comprising:a valve assembly positioned to control fluid flow between the source of fluid and the actuator, wherein the controller is communicatively coupled to the valve assembly.

18. The system of claim 16, wherein each sensing container of the one or more sensing containers is tuned for a particular range of pressure where precise control is desired.

19. The system of claim 16, wherein gas in the respective gas chambers of the the one or more sensing containers is precharged to different pressure levels to enable pressure sensing across different pressure ranges.

20. The system of claim 16, further comprising:an implement coupled to the actuator, wherein the controller is configured to control force applied by the implement based on the determined pressure levels.

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