System and method for delivering proppant to a blender

Abstract

A system for conveying proppant includes a conveyor assembly having a conveyor belt that receives proppant from one or more containers having proppant stored therein. The system also includes a conveyor auxiliary unit connected to an end of the conveyor assembly having one or more joints to enable expansion and collapse of the conveyor belt from the conveyor assembly. The system further includes a proppant chute to direct the proppant from the conveyor belt into a blending hopper, the proppant chute being positioned at a higher elevation than an inlet of the blending hopper.

Description

BACKGROUND

Summary

In an embodiment, a system for conveying proppant includes a conveyor assembly having a conveyor belt, the conveyor belt receiving proppant from one or more containers having proppant stored therein distributed along the conveyor assembly and carrying the proppant away from the containers. The system also includes a conveyor auxiliary unit connected to an end of the conveyor assembly having one or more joints to enable expansion and collapse of the conveyor belt from the conveyor assembly so as further to extend along the conveyor auxiliary unit. The system further includes a proppant chute positioned at an end of the conveyor auxiliary unit, the proppant chute having an opening to direct the proppant from the conveyor belt into a blending hopper, the proppant chute being positioned at a higher elevation than an inlet of the blending hopper such that the proppant exits the proppant chute into the blending hopper via gravity feed.

In another embodiment, a system to convey proppant includes a conveyor assembly to receive and support one or more containers having proppant stored therein. The system also includes a conveyor belt positioned beneath the one or more containers to receive the proppant dispensed from the one or more containers and to transport the proppant away from the one or more containers. Moreover, the system includes a conveyor auxiliary unit positioned at an end of the conveyor assembly, the conveyor auxiliary unit having an inclined section that increases a vertical position of the conveyor belt relative to a ground plane, one or more joints positioned along the conveyor assembly to enable expansion and compaction of the conveyor belt, and a proppant chute positioned at the end of the conveyor assembly, the proppant chute moveable to direct the proppant away from the convey belt. Additionally, the system includes a blending hopper positioned proximate the conveyor assembly to receive and mix the proppant with one or more proppant fluids for injection into a well. The system also includes a tub positioned at an inlet of the blending hopper between the blending hopper and the proppant chute, the tub being removable from the blending hopper and positioned at a lower elevation than the proppant chute when coupled to the blending hopper.

In a further embodiment, a method includes dispensing proppant from a container positioned on a conveyor assembly onto a conveyor belt. The method also includes transporting the proppant, via the conveyor belt, away from the container and toward a conveyor assembly. The method further includes transferring the proppant to a proppant chute such that the elevation of the proppant on the conveyor belt is increased. The method also includes directing the proppant into a blending hopper via gravity feed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear perspective view of a blender unit, in accordance with embodiments of the present disclosure;

FIG. 2 is a side elevational view of the blender unit of FIG. 1, in accordance with embodiments of the present disclosure;

FIG. 3 is a top plan view of the blender unit of FIG. 1, in accordance with embodiments of the present disclosure;

FIG. 4 is a side elevational view of a blender unit and proppant delivery system, in accordance with embodiments of the present disclosure;

FIG. 5 is a partial side elevational view of a conveyor auxiliary unit, in accordance with embodiments of the present disclosure;

FIG. 6 is a partial side elevational view of a conveyor auxiliary unit, in accordance with embodiments of the present disclosure;

FIG. 7 is a partial side elevational view of a chute of a conveyor assembly, in accordance with embodiments of the present disclosure;

FIG. 8 is a rear perspective view of a chute positioned over a blending hopper, in accordance with embodiments of the present disclosure; and

FIG. 9 is a rear perspective view of a chute positioned over a blending hopper, in accordance with embodiments of the present disclosure.

DETAILED DESCRIPTION

The foregoing aspects, features, and advantages of the present disclosure will be further appreciated when considered with reference to the following description of embodiments and accompanying drawings. In describing the embodiments of the disclosure illustrated in the appended drawings, specific terminology will be used for the sake of clarity. However, the disclosure is not intended to be limited to the specific terms used, and it is to be understood that each specific term includes equivalents that operate in a similar manner to accomplish a similar purpose.

When introducing elements of various embodiments of the present disclosure, the articles “a”, “an”, “the”, and “said” are intended to mean that there are one or more of the elements. The terms “comprising”, “including”, and “having” are intended to be inclusive and mean that there may be additional elements other than the listed elements. Any examples of operating parameters and/or environmental conditions are not exclusive of other parameters/conditions of the disclosed embodiments. Additionally, it should be understood that references to “one embodiment”, “an embodiment”, “certain embodiments”, or “other embodiments” of the present disclosure are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Furthermore, reference to terms such as “above”, “below”, “upper”, “lower”, “side”, “front”, “back”, or other terms regarding orientation or direction are made with reference to the illustrated embodiments and are not intended to be limiting or exclude other orientations or directions.

FIGS. 1-3 illustrate a proppant blender unit 10 mounted on a trailer 12 for ease of transport. In operation, the blender unit 10 mixes proppant at a well site prior to introduction of the proppant into a well during a hydraulic fracturing operation. In the illustrated embodiment, the blender unit 10 has a tub 14 for receiving proppant from a conveyor (not shown). As shown, the tub 14 is arranged to receive the proppant and includes walls to enable large volumes of proppant to be stored in the tub 14 before the proppant is transported along the blender unit 10. For example, in certain embodiments, proppant may be loaded into the tub 14 and gradually moved along the blender unit 10 as the proppant is transported via one or more moving devices, such as augers. As illustrated, an inlet of a blending hopper 18 is arranged at a higher elevation than the tub 14. As a result, the proppant positioned in the tub 14 is lifted to a higher elevation to enable deposition into the blending hopper 18. In the illustrated embodiment, auger units 20 extend from the tub 14 to the inlet 16 and move and direct the proppant out of the tub 14. Furthermore, as shown in FIG. 1, the auger units 20 include an auger housing 22 that encases an auger screw (now shown). As the auger screw turns, the surfaces of the screw lift the proppant from the tub 14, through the auger housing 22 and upward to the inlet 16 of the blending hopper 18. At the inlet 16 of the blending hopper 18, the proppant is expelled from the auger housing 22 into the inlet 16 through a proppant chute 24.

Fracking proppant is a highly dense, often very hard and/or coarse material. As a result, the auger screws of the auger units 20 can quickly become worn and ineffective. For example, the friction between the proppant and the auger screws may wear down the helical sweep of the screw, thereby reducing the amount of proppant the auger screws can transport. In this manner, the blending of proppant has reduced efficiencies that may lead to delays in production and fracturing operations at a well site. Moreover, because the auger screws may be worn quickly, stoppages in work may be frequent to replace the auger screws. Again, stoppages to replace the auger screws reduce the efficiencies of the fracturing operations, thereby increasing costs.

Embodiments of the present disclosure include a conveyor auxiliary unit used in conjunction with a system for delivering proppant. As will be described below, by utilizing the conveyor auxiliary unit, the tub 14 may be positioned directly above the inlet 16 of the blending hopper 18. As a result, use of the auger units 20 can be eliminated, thereby improving efficiencies at the well site.

FIG. 4 is a schematic side elevational view of an embodiment of a proppant delivery system 100 arranged proximate a well site having a proppant blender unit 110. It should be appreciated that certain features of the proppant delivery system 100 have been omitted for clarity and conciseness in the foregoing discussion. The proppant delivery system 100 utilizes modular, stackable, sealed proppant containers 132 to transport proppant for delivery, dispersion, and use at the well site. For example, the proppant containers 132 may be loaded onto trucks and transported to the well site from a sand mine, transloading facility, or the like. Moreover, the modular, pre-loaded boxes reduce demurrage typically experienced at well sites due to unloading sand from bulk pneumatic containers. It will be appreciated that, in certain embodiments, features of the proppant delivery system enable the efficient loading, unloading, and transportation of proppant at the well site.

In the illustrated embodiment, the proppant delivery system 100 includes a conveyor assembly 128 having a conveyor belt 130 positioned to underlie the containers 132. In certain embodiments, the conveyor assembly 128 includes a surface 136 to receive and support the containers 132 in a side-by-side configuration. As a result, the containers 132 can be positioned above the conveyor belt 130 to enable gravity feed of the proppant out of the containers 132. The conveyor belt 130 collects sand from the proppant containers 132 directly from the outlets (not shown) in the bottom of the respective containers 132. As the conveyor belt 130 receives the proppant, the conveyor belt 130 transports the proppant along the length of the surface 136 to an elevated section 138 of the conveyor assembly 128. As will be described below, the conveyor belt 130 continues through the elevated section 138 and extends to a chute 126 arranged above the inlet 116 of the tub 114. In the illustrated embodiment, the elevated section 138 is at an elevation higher than an elevation of the conveyor belt 130 when the conveyor belt 130 is positioned below the containers 132. That is, the elevated section 138 is higher than the surface 136. In this manner, the conveyor belt 130 can transport the proppant to the chute 126 for deposition into the tub 114 and the blending hopper 118 without utilizing the auger units 20 because the tub 114 can gravity feed the proppant into the inlet 116 of the blending hopper 118.

In the illustrated embodiment, the conveyor assembly 128 is collapsible and extendable by use of the conveyor auxiliary unit 140. That is, the conveyor auxiliary unit 140 enables expansion and collapse of the conveyor belt 130. As shown, the conveyor auxiliary unit 140 is coupled to the conveyor assembly 128 via one or more joints 134. In certain embodiments, the joint 134 is coupled to the conveyor assembly 128 via a hinged and/or ball-and-socket configuration. That is, the joint 134 enables the conveyor auxiliary unit 140 to pivot about an axis. In the illustrated embodiment, the conveyor auxiliary unit 140 includes the chute 126 positioned at a far end 142. The chute 126 is coupled to the conveyor auxiliary unit 140 via a pivoting connection 144 driven by an actuator 146 coupled to a control system 148. As will be described below, the actuator 146 enables the chute 126 to rotate about an axis, thereby facilitating different positions of the chute 126 to accommodate a variety of well site configurations.

In certain embodiments, the joint 134 enables compact storage of the conveyor assembly 128 and/or the conveyor auxiliary unit 140 while the proppant delivery system 100 is not in use. Moreover, the joint 134 enables the conveyor auxiliary unit 140 to collapse during transportation of the proppant delivery system 100, thereby reducing the height of the proppant delivery system for travel along roadways having height and/or weight restrictions for commercial loads. Moreover, the joint 134 enables use of the conveyor assembly 128 and the conveyor auxiliary unit 140 with both elevated blending hoppers 118 and conventional blending units where the hopper is close to the ground. As such, removal of the conveyor auxiliary unit 140 will not be necessary when utilizing multiple different blending units on one well site, thereby improving efficiencies and increasing the variety of equipment suitable for use with the proppant delivery system 100.

In certain embodiments, the joint 134 includes a slot and pin connection 152 to enable movement of the joint 134 (e.g., rotation of the conveyor auxiliary unit 140 about the axis) a predetermined distance. For example, the pin fits within the slot and travels the circumferential difference allowed by the slot. In this manner, over-rotation of the conveyor auxiliary unit 140 may be reduced, thereby improving longevity and decreasing wear and tear on the equipment.

Furthermore, in certain embodiments, the tub 114 may be removable from the blending hopper 118 to also enable transportation along roadways. For example, the tub 114 may be removed and stored when the proppant blender unit 110 is not in operation. In certain embodiments, the tub 114 may be stored on the trailer 12 of the proppant blender unit 110 to keep the tub 114 close by the blending hopper 118 to reduce the likelihood of losing or damaging the tub 114.

As described above, the control system 148 may be utilized to monitor and control operations of the proppant delivery system 100. For example, one or more sensors 150 may be utilized to measure the flow of proppant into the blending hopper 118, measure the weight of the proppant in the tub 114 and/or the containers 132, measure a speed of the conveyor belt 130, measure the rate of discharge from the containers 132, measure a proppant level in the tub 114, or the like. As will be known by one skilled in the art, the position of these sensors 150 and the types of sensors used may vary based on the application. For example, a weight sensor may be used to measure the weight of proppant in the tub 114, and thereby the flow of proppant into the blending hopper 118, while a speed sensor may be used to monitor the speed of the conveyor belt 130.

FIG. 5 is a partial schematic side elevational view of the conveyor assembly 128 and the conveyor auxiliary unit 140. In the illustrated embodiment, a cover 160 arranged about the conveyor assembly 128 and the conveyor auxiliary unit 140 is partially removed for clarity. In the illustrated embodiment, the conveyor belt 130 extends along the conveyor assembly 128 and the conveyor auxiliary unit 140 toward the chute 126. As shown, the conveyor belt 130 in the illustrated embodiment is an endless conveyor that loops around at each end, thereby facilitating transportation of the proppant from the containers 132. The proppant is transported along the conveyor belt 130 and deposited into the tub 114 positioned above the inlet 116 of the blending hopper 118. In this manner, the auger units 20 may be eliminated, thereby improving efficiencies of fracturing operations.

As illustrated, the joint 134 is a ball-and-socket connection in which the conveyor auxiliary unit 140 is coupled to the conveyor assembly 128 and pivotable about an axis 162. That is, the conveyor auxiliary unit 140 can increase its elevation relative to a ground plane by rotating about the axis 162 in a first direction 164 and decrease its elevation relative to the ground plane by rotating about the axis 162 in the second direction 166. As illustrated, the joint 162 includes a fastener 168 (e.g., a pin, a bolt, a rod, a geared tooth, etc.) to rotatably couple the conveyor auxiliary unit 140 to the conveyor assembly 128. Moreover, as illustrated, the conveyor auxiliary unit end 170 acts as the ball and the conveyor assembly end 172 acts as the socket to enable rotation of the conveyor auxiliary unit 140 about the axis 162. That is, the conveyor auxiliary unit end 170 may fit into the conveyor assembly end 172. However, it should be appreciated, that in other embodiments the joint 134 may be of a different type. For example, the joint 134 may be a hinge joint, a screw joint, a saddle joint, a plane joint, an ellipsoid joint, a universal joint, an elbow joint, or the like. It should be appreciated that the joint 134 is utilized to facilitate a rotatable connection between the conveyor assembly 128 and the conveyor auxiliary unit 140, and therefore, a variety of different connections may be utilized without departing from the scope of the present disclosure. As a result, the conveyor auxiliary unit 140 may be utilized to position the chute 126 over the tub 114 to enable gravity feed of the proppant into the blending hopper 118.

In the illustrated embodiment, the control system 148 is communicatively coupled to a control hub 174. However, it should be appreciated that, in certain embodiments, the control hub 174 may not be utilized. For example, all actuators, drivers, sensors, and the like in the system may be communicatively coupled directly to the control system 148. As described above, in certain embodiments, the actuator 146 is arranged proximate the pivoting connection 144 to enable movement of the chute 126 to accommodate different configurations at a well site. Moreover, in certain embodiments, the control hub 174 may be communicatively coupled to the joint 134 to direct movement of the joint about the axis 162. However, as described above, the joint 134 may be in direct communication with the control system 148. For example, the joint 162 may include a drive unit 176, such as an electric motor and gear unit, to drive movement of the conveyor auxiliary unit 140 about the axis 162. In this manner, an operator can control the position of the conveyor auxiliary unit 140 from a distance, thereby reducing the likelihood of interference with ongoing fracturing operations. However, in certain embodiments, the position of the conveyor auxiliary unit 140 may be manually operated. Additionally, the fastener 168 may include stops to block rotation of the conveyor auxiliary unit 140. Moreover, the stops may be utilized to block over-rotation of the conveyor auxiliary unit 140.

FIG. 6 is a partial schematic side elevational view of an embodiment of the conveyor auxiliary unit 140 moving in the first direction 164 to thereby increase an elevation of the chute 126 relative to the ground plane. As shown, the conveyor auxiliary unit 140 rotates in the first direction 164 about the axis 162 to raise the elevation of the chute 126 relative to the ground plane and above the tub 114. In this manner, proppant blender units 110 with elevated blending hoppers 118 may receive proppant via the chute 126 to a tub 114 arranged directly over the blending hopper 118, thereby eliminating the need for the auger units 20 and improving overall efficiency and reliability of fracturing operations. In the illustrated embodiment, the slot and pin connection 152 restricts rotation of the conveyor auxiliary unit 140. In certain embodiments, the drive unit 176 controls movement of the conveyor auxiliary unit 140 via the control system 148. In certain embodiments, the stops are operable with the drive unit 176 to block over-rotation of the conveyor auxiliary unit 140. However, in other embodiments, the conveyor auxiliary unit 140 may be manually moved to rotate about the axis 162. As illustrated, even when the elevation of the chute 126 is increased, relative to the ground plane, the conveyor belt 130 is still arranged within the conveyor assembly 128 and the conveyor auxiliary unit 140 such that the proppant can be delivered to the blending hopper 118 via the chute 126.

FIG. 7 is a partial schematic side elevational view of the chute 126 directing proppant into the tub 114 arranged above the blending hopper 118 through an opening in the chute 126. As illustrated, the proppant is conveyed along the conveyor belt 130 toward the chute 126. From the chute 126, the proppant is gravity fed downward into the tub 114 arranged over the inlet 116 of the blending hopper 118. As described above, by positioning the tub 114 over the blending hopper 118 the use of the auger units 20 may be eliminated, thereby reducing the likelihood of work stoppages for repair and replacement of the auger screws.

In the illustrated embodiment, the sensor 150 is arranged proximate the tub 114 to monitor the weight of the proppant in the tub 114. For example, the sensor 150 may include a weight sensor that is in communication with the control system 148 (e.g., via a wired or wireless communication system), such as via BLUETOOTH, IEEE 802.11 networks, cellular networks, Ethernet, USB, or the like. In certain embodiments, the control system 148 may receive information from the sensor 150 (such as the weight of proppant in the tub 114) and change operation of the proppant delivery system 110 based on the information. For example, if the weight of the proppant in the tub 114 is over some predetermined threshold, the control system 150 may be utilized to slow the speed of the conveyor belt 130 and/or slow the drainage of proppant from the containers 132 to prevent overfilling the tub 114. Moreover, if the weight of the proppant in the tub 114 is too low, the control system 148 may speed up the conveyor belt 130, thereby directing more proppant to the tub 114. Similarly, other sensors 150 may be utilized in a similar manner to control operations of the proppant delivery system 100. For example, the speed of the conveyor 130, the weight of the proppant in the tub 114, the level in the tub 114, the rate of discharge from the containers 132, and the like may all be utilized to determine an efficient discharge and blending pace, thereby improving efficiencies and reducing undue strain on associated support equipment.

As illustrated in FIG. 7, the chute 126 is directed toward the tub 114 via the pivoting connection 144, controlled by the actuator 146 communicatively coupled to the control system 148. In certain embodiments, the actuator 146 may be coupled to the control hub 174. The actuator 146 drives rotational movement of the chute 126 to thereby direct the proppant to a desired location. In the illustrated embodiment, the desired location is the tub 114. However, it should be appreciated that the chute 126 may direct the proppant directly into the blending hopper 118, or any other suitable location.

FIG. 8 is a rear perspective view of an embodiment of the chute 126 directing the proppant into the tub 114. As illustrated, the proppant is directed along the conveyor belt 130 through the conveyor assembly 128 and the conveyor auxiliary unit 140 toward the chute 126 for deposition within the tub 114. As described above, the chute 126 is arranged proximate the pivoting connection 144 to enable rotation about an axis 190 via the actuator 146. Rotation of the chute 126 enables operators to select the location of the proppant within the tub 114, thereby improving operating procedures. For example, if the operator notices that proppant is collecting or piling in a particular area of the tub 114, the operator can rotate the chute 126 (e.g., via the control system 148) to change the location of proppant deposition within the tub 114. As a result, operations are not halted to adjust the proppant within the tub 114.

In the illustrated embodiment, the pivoting connection 114 includes a slot 192 that receives a pin 194 to enable rotation of the chute 126 a predetermined distance about the axis 190. That is, the pin 194 extends into the slot 192 and travels a circumferential distance enabled by the slot 192. As described above, the actuator 146 may drive movement of the chute 126, and thereby drive movement of the pin 194 within the slot 192. However, it should be appreciated that other methods may be utilized to control the pivoting and/or rotation of the chute 126. For example, stops may be utilized to block rotation of the chute 126. In this manner, via the actuator 146, the chute 126 may rotate about the axis 190 in a first direction 196 and a second direction 198. Moreover, in certain embodiments, the chute 126 may be manually operated.

FIG. 9 is a rear perspective view of the chute 126 directing the proppant into the tub 114. As shown, compared to FIG. 8, the chute 126 has rotated in the first direction 196 such that the pin 194 is arranged at the end of the slot 192. That is, in the illustrated embodiment, the chute 126 has rotated as far in the first direction 196 as enabled by the slot 192. As described above, the actuator 146 drives movement of the chute 126 about the axis 190. In this manner, the proppant can be directed into the tub 114 such that the proppant does not pile up at one location, thereby enabling more efficient, smooth operation of the fracturing process. For example, if the proppant were to pile up in one location in the tub, the sensor 150 monitoring the level in the tub 114 may inadvertently send a signal to the control system 148 indicative of the high level, thereby interrupting operations. However, because of the pivoting chute 126, the proppant may be evenly distributed within the tub 114, thereby reducing the likelihood of the proppant piling up in one location.

As described above, the proppant delivery system 100 may be utilized with the proppant blender unit 110 to facilitate hydraulic fracturing operations. For example, proppant may be dispensed from the containers 132 onto the conveyor belt 130. The containers 132 are positioned on the conveyor assembly 128, in the illustrated embodiment. As the proppant is deposited on the conveyor belt 130, the proppant is transported, via the conveyor belt 130, away from the containers 132 and toward the conveyor auxiliary unit 140. Thereafter, the proppant is transferred from the conveyor belt 130 to the chute 126 such that the elevation of the proppant on the conveyor belt is increased. In other words, the proppant is transported along the elevated section 138 such that the elevation of the proppant is increased relative to the ground plane. Next, the proppant is directed into the blending hopper 118 via gravity feed. For example, the chute 126 and conveyor auxiliary unit 140 may position the proppant at an elevation greater than the blending hopper 118 and/or the tub 114. As a result, the proppant can be gravity fed from the chute 126 into the tub 114 and/or the blending hopper 118, thereby eliminating the use of the auger units 20. Moreover, in certain embodiments, the sensors 150 positioned about the system may be utilized to control operations via the control system 148. For example, the flow rate of the proppant to the blending hopper 118 can be adjusted via the control system 148 based on feedback from the sensor 150 monitoring the weight of the proppant in the tub 114. Moreover, the speed of the conveyor belt 130 may be adjusted based on feedback from the one or more downstream sensors 150 arranged along the system. In this manner, the control system 148, based on feedback from the various sensors 150, may control delivery of proppant to the blending hopper 118.

This application is a continuation, and claims priority to, and the benefit of, U.S. Non-Provisional application Ser. No. 15/260,371, filed Sep. 9, 2016, titled “System and Method for Delivering Proppant To A Blender,” which is a continuation-in-part of U.S. Non-Provisional application Ser. No. 14/854,622, filed Sep. 15, 2015, titled “System and Method for Delivering Proppant To A Blender,” which claims priority to, and the benefit of U.S. Provisional Application No. 62/217,117, filed Sep. 11, 2015, titled “System and Method for Delivering Proppant To A Blender” and U.S. Provisional Application No. 62/050,752, filed Sep. 15, 2014, titled “System and Method for Delivering Proppant To A Blender,” each of which are incorporated herein by reference in their entireties.

The foregoing disclosure and description of the disclosed embodiments is illustrative and explanatory of the embodiments of the invention. Various changes in the details of the illustrated embodiments can be made within the scope of the appended claims without departing from the true spirit of the disclosure. The embodiments of the present disclosure should only be limited by the following claims and their legal equivalents.

Claims

1. A method of moving proppant at a fracturing site, the method comprising: dispensing proppant from a plurality of containers positioned in a side by side arrangement on a conveyor assembly onto a conveyor belt;transporting the dispensed proppant, via the conveyor belt, away from the plurality of containers and toward a conveyor auxiliary unit;

2. The method of claim 1, further comprising directing the proppant into a tub positioned between the proppant chute and the blending hopper, the tub being removable from the blending hopper and having a lower elevation than the proppant on the conveyor belt.

3. The method of claim 1, further comprising adjusting a flow rate of the proppant to the blending hopper via a control system based on feedback from a weight sensor, the weight sensor outputting a signal to the control system indicative of a quantity of proppant flowing to the blending hopper.

4. The method of claim 1, further comprising adjusting a flow rate of the proppant from each of the plurality of containers via a control system based on feedback from one or more sensors positioned adjacent the conveyor assembly.

5. The method of claim 4, further comprising adjusting a speed of the conveyor belt via feedback from the one or more sensors.