System and method for material handling vehicle tiller arm angle detection

Abstract

The invention relates to a system and method for material handling vehicle tiller arm angle detection. A tiller arm detection system for a material handling vehicle may include a tiller arm having a cam assembly. The cam assembly may include a first cam having a first surface profile and a second cam having a second, different surface profile. The tiller arm detection system may further include a first sensor to detect a portion of the first cam; a second sensor for detecting a portion of the second cam; and a controller for communicating with the first sensor and the second sensor to determine a position of the tiller arm based on the detected portion of the first cam or the second cam. The controller may activate the feedback system based on the detected portion of the first cam or the second cam.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application No. 63 / 523,589, filed on June 27, 2023, which is incorporated herein by reference in its entirety. Background Art

[0002] Material handling vehicles are commonly found in warehouses, factories, shipping yards, and generally anywhere that pallets, packages, or cargo are moved from one place to another. A material handling vehicle typically includes load carrying forks (e.g., for supporting a load), a motor, a steering system, and brakes. In some examples, a material handling vehicle may include an operator station from which an operator may control (e.g., operate) the material handling vehicle. Summary of the invention

[0003] In one aspect, the present disclosure describes a tiller arm detection system for a material handling vehicle. The tiller arm detection system may include a tiller arm having a cam assembly. The cam assembly may include a first cam having a first surface profile and a second cam having a second, different surface profile. The tiller arm detection system may also include: a first sensor for detecting a portion of the first cam; a second sensor for detecting a portion of the second cam; and a controller for communicating with the first sensor and the second sensor to determine a position of the tiller arm based on the detected portion of the first cam or the second cam. The controller may activate a feedback system based on the detected portion of the first cam or the second cam.

[0004] In another aspect, the present disclosure describes a method of providing feedback to an operator of a material handling vehicle. The method may include: detecting a first cam of a cam assembly disposed at one end of a tiller arm of the material handling vehicle via a first sensor, the first cam defining a first surface profile; detecting a second cam of the cam assembly via a second sensor, the second cam defining a different second surface profile; determining a position of the tiller arm via a controller in communication with the first sensor and the second sensor; and activating a feedback system of the material handling vehicle based on the position of the tiller arm to provide feedback to the operator corresponding to the position of the tiller arm.

[0005] In another aspect, the present disclosure describes a tiller arm for a material handling vehicle. The tiller arm may include a cam assembly having: a first cam having a first protrusion defining a first surface profile; and a second cam arranged substantially parallel to the first cam and laterally spaced from the first cam. The second cam may include a second protrusion and a third protrusion separated by a gap, the second protrusion, the third protrusion, and the gap defining a second surface profile. In one example, the first cam is arranged such that the first protrusion of the first cam is substantially arranged within a gap formed between the second protrusion and the third protrusion of the second cam. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present invention and, together with the description, serve to explain the principles of the embodiments of the present invention:

[0007] Figure 1 is a diagrammatic view of a material handling vehicle in accordance with aspects of the present disclosure.

[0008] Figure 2 According to various aspects of the present disclosure Figure 1 An axonometric view of an example of a material handling vehicle.

[0009] Figure 3 According to various aspects of the present disclosure Figure 2 Side view of a material handling vehicle.

[0010] Figure 4 According to various aspects of the present disclosure, Figure 1 A plan view of a tiller arm detection system for use with a material handling vehicle.

[0011] Figure 5 According to various aspects of the present disclosure, Figure 4 A first side view of a tiller arm used in conjunction with the tiller arm detection system.

[0012] Figure 6 According to various aspects of the present disclosure Figure 5 Second side view of the tiller arm.

[0013] Figure 7 According to various aspects of the present disclosure, Figure 4 A first side view of a cam assembly of a tiller arm detection system.

[0014] Figure 8 is in the second position according to various aspects of the present disclosure, Figure 4 A first side view of a cam assembly of a tiller arm detection system.

[0015] Fig. 9 According to various aspects of the present disclosure, Figure 4 A first side view of a cam assembly of a tiller arm detection system.

[0016] Fig.10 According to various aspects of the present disclosure, Figure 4 A second side view of the cam assembly of the tiller arm detection system.

[0017] Fig.11 is in the second position according to various aspects of the present disclosure, Figure 4 A second side view of the cam assembly of the tiller arm detection system.

[0018] Fig.12 According to various aspects of the present disclosure, Figure 4 A second side view of the cam assembly of the tiller arm detection system.

[0019] Fig.13 According to various aspects of the present disclosure, Figure 4 A second side view of the cam assembly of the tiller arm detection system.

[0020] Fig.14 According to various aspects of the present disclosure, the fifth position Figure 4 A second side view of the cam assembly of the tiller arm detection system.

[0021] Fig.15 According to various aspects of the present disclosure, the first position is used for Figure 1 A second side view of a cam assembly of another example of a tiller arm detection system for use with a material handling vehicle.

[0022] Fig.16 is in the second position according to various aspects of the present disclosure, Fig.15 A second side view of the cam assembly of the tiller arm detection system.

[0023] Fig.17 According to various aspects of the present disclosure, Fig.15 Second side view of the cam assembly of the tiller arm detection system.

[0024] Fig.18 According to various aspects of the present disclosure, the first position is used for Figure 4 A first side view of another example of a cam assembly for use with a tiller arm detection system.

[0025] Fig.19 is in the second position according to various aspects of the present disclosure, Fig.18A first side view of a cam assembly.

[0026] Fig. 20 According to various aspects of the present disclosure, Fig.18 A first side view of a cam assembly. DETAILED DESCRIPTION

[0027] The following discussion is provided to enable those skilled in the art to make and use embodiments of the present invention. In view of the benefit of this disclosure, various modifications to the illustrated embodiments will be readily apparent to those skilled in the art, and the principles herein may be applied to other embodiments and applications without departing from embodiments of the present invention. Thus, embodiments of the present invention are not intended to be limited to the embodiments shown, but should conform to the widest scope consistent with the principles and features disclosed herein.

[0028] The following detailed description is read with reference to the accompanying drawings, wherein the same elements in different drawings have the same reference numerals. The accompanying drawings depict selected embodiments and are not intended to limit the scope of embodiments of the present invention, and the accompanying drawings are not necessarily to scale. Those skilled in the art will recognize that the examples provided herein have many useful alternatives and fall within the scope of embodiments of the present invention.

[0029] Before explaining any embodiment of the present invention in detail, it should be understood that the present invention is not limited to the construction details and component arrangements set forth in the following specification or illustrated in the accompanying drawings in this application. The present invention can be applied to other embodiments and can be practiced or executed in various ways. Moreover, it should be understood that the wording and terminology used herein are for descriptive purposes and should not be considered restrictive. In this article, the use of "including", "comprising" or "having" and its variants is meant to cover the items listed later and their equivalents and additional items. Unless otherwise specified or limited, the terms "install", "connect", "support" and "couple" and their variants are widely used and cover direct and indirect installation, connection, support and coupling. Further, "connect" and "couple" are not limited to physical or mechanical connections or couplings.

[0030] It should also be appreciated that material handling vehicles (MHVs) are designed in various categories and configurations to perform various tasks. It will be apparent to those skilled in the art that the present disclosure is not limited to any particular MHV and may also be provided with various other types of MHV categories and configurations (including, for example, lift trucks, forklifts, reach trucks, SWING The present invention relates to a material handling vehicle, a turret truck, a side-loading truck, a counterbalanced lift truck, a pallet stacker truck, a command sorter, a transfer truck, a tractor, and a man-up truck), and can be commonly found in warehouses, factories, shipyards, and (generally speaking) anywhere where pallets, large packages, or cargo loads are typically required to be transported from one place to another. The various systems and methods disclosed herein are applicable to any of the following: operator-controlled material handling vehicles, pedestrian-controlled material handling vehicles, remotely-controlled material handling vehicles, and autonomously-controlled material handling vehicles. Further, the present disclosure is not limited to material handling vehicle applications. On the contrary, the present disclosure can be provided for use with other types of vehicles, such as automobiles, buses, trains, tractor trailers, agricultural vehicles, factory vehicles, etc.

[0031] It should be noted that the various material handling vehicles (MHVs) listed above can perform various load handling operations. For example, the MHV can operate the MHV and / or the load handling portion of the MHV (e.g., forks, mast, and / or fork frame, etc.) to pass (e.g., move the forks up to a full load depth), dump, extend (e.g., move the forks up to a partial load depth), rotate, drive (e.g., move the MHV), travel (e.g., move the MHV), and / or perform any combination thereof to complete a load handling operation.

[0032] It should be noted that for certain types of vehicles, there are training requirements stipulated by various government agencies, laws, regulations and ordinances. For example, OSHA stipulates that employers are obliged to train and supervise operators of various types of material handling vehicles. It is also required to re-certify every three years. In some instances, operators should be provided with refresher training on related topics when necessary. In all instances, during the execution of any action, the operator maintains control of the material handling vehicle. Further, the warehouse manager maintains control of the fleet of material handling vehicles in the warehouse environment. The training of the operator and the supervision to be provided by the warehouse manager require appropriate operating practices, etc., including that the operator maintains control of the material handling vehicle, pays attention to the operating environment, and always looks at the direction of travel, etc.

[0033] Conventional material handling vehicles may include a tiller arm for controlling the operation of the material handling vehicle. For example, the tiller arm may be utilized by an operator to steer, advance (e.g., move), or brake the material handling vehicle. However, during use of the tiller arm, the operator may be unaware of the position of the tiller arm relative to the braking or operating position of the tiller arm.

[0034] Examples of the present disclosure may address these issues, for example, by providing a tiller arm detection system that monitors the position of the tiller arm. The tiller arm detection system may also communicate with a feedback system to provide feedback to an operator indicating the position of the tiller arm relative to the braking area or operating area. In some examples, the feedback may include audible, tactile, visual, or mechanical feedback.

[0035] Further, to determine the position of the tiller arm, the tiller arm may include a cam assembly at one end, the cam assembly including a first cam arranged parallel to and laterally offset from a second cam. The first and second cams may include different surface profiles configured to interact with the first and second sensors. For example, the first cam may include a first protrusion, and the second cam may include a second protrusion and a third protrusion separated by a gap. In some examples, the first and second cams may be arranged such that the first protrusion is aligned with the gap between the second and third protrusions.

[0036] During movement of the tiller arm, the first sensor may detect the first protrusion to determine whether the tiller arm is in the braking region (when the first protrusion is not detected) or in the operating region (when the first protrusion is detected). Correspondingly, the second sensor may detect the second protrusion or the third protrusion to determine whether the tiller arm is in the first transition region (when the second protrusion is detected) or the second transition region (when the third protrusion is detected). In some examples, when the tiller arm is determined to be in the first or second transition region, the feedback system may provide feedback indicating the position of the tiller arm. In some examples, the first sensor may detect the first protrusion, while the second sensor detects the second or third protrusion.

[0037] Figure 1An example of a material handling vehicle (MHV) 100 including a tiller arm detection system 128 is shown. In one example, the tiller arm detection system 128 may be configured to determine a position (e.g., an angular position) of a tiller arm 112 of the material handling vehicle 100. For example, the tiller arm detection system 128 may include and communicate with one or more sensors 124 (e.g., a proximity sensor, a distance sensor, etc.) to detect the position of the tiller arm 112 during operation of the material handling vehicle 100. In some examples, based on the position of the tiller arm 112, the controller 120 may output a command to the feedback system 104 that may indicate to the operator that the tiller arm 112 is approaching a braking position (e.g., a substantially horizontal or vertical position of the tiller arm 112). In some examples, the feedback system 104 may include tactile feedback, visual feedback, audible feedback, mechanical feedback, or any combination thereof. It should be appreciated that the feedback system 104 may mitigate situations in which an operator inadvertently activates the brakes 116 of the material handling vehicle 100 during operation of the vehicle.

[0038] In some examples, the material handling vehicle 100 can include a power source 132 (e.g., an electric motor, an internal combustion engine, etc.), which can be operably connected to one or more wheels 108 for moving the material handling vehicle 100. In some examples, the power source 132 and the wheels 108 can be operably connected to the tiller arm 112 so that the tiller arm 112 can control the operation of the material handling vehicle 100 (e.g., control the speed of movement, direction, etc.). For example, the tiller arm 112 can be rotated or otherwise manipulated by an operator to control the speed and direction of movement of the material handling vehicle 100. As described above, the material handling vehicle 100 includes a brake 116, which can be activated or deactivated based on the position of the tiller arm 112. For example, when the tiller arm is in a first (e.g., home) position, the brake 116 can be automatically activated. In one example, the first position of the tiller arm can correspond to a substantially vertical arrangement of the tiller arm 112. In some examples, the brake 116 may also be activated when the tiller arm 112 is in a substantially horizontal position.

[0039] In some examples, before actuating the brakes 116, the controller 120 may activate the feedback system 104 to warn the operator that the brakes 116 may soon be engaged. For example, the controller 120 may determine the angular position of the tiller arm 112 via the sensor 124, and send feedback to the operator indicating that further movement (e.g., rotation) of the tiller arm 112 may activate the brakes 116 based on the position of the tiller arm 112. Thus, the feedback system 104 may mitigate against unintentional activation of the brakes 116 during operation of the material handling vehicle 100. In some examples, the feedback system 104 may provide feedback to the operator via one or more lights, audible feedback, tactile feedback (e.g., haptic feedback), or mechanical feedback (e.g., slowing down the movement of the material handling vehicle 100).

[0040] Figure 2 An example of a material handling vehicle 100 is shown, which may include a body 200 having one or more forks 204 extending from a first end 205 of the body 200. The forks 204 may be configured to lift, hold, or otherwise transport a load during operation of the material handling vehicle 100. In some examples, a tiller arm 112 may extend from an opposing second end 215 of the body 200. As previously described, the tiller arm 112 may be rotatably coupled to the body 200. For example, the tiller arm 112 may rotate relative to the body 200 about a vertical axis 228 (e.g., an axis substantially perpendicular to a ground plane supporting the material handling vehicle 100). Further, the tiller arm 112 may also rotate about a horizontal axis 232 (e.g., an axis substantially perpendicular to the vertical axis 228). In some examples, rotating the tiller arm 112 about the vertical axis 228 may steer the material handling vehicle 100 (e.g., via movement of the wheels 108). Accordingly, rotation of the tiller arm 112 about the horizontal axis 232 may activate or deactivate the brake 116 to allow movement of the material handling vehicle 100. In some examples, the tiller arm 112 may include a handle 445 (see, e.g., Figure 4 ) to allow the operator to hold and operate the tiller arm 112.

[0041] Reference now Figure 3, the tiller arm 112 may be rotatable through a plurality of positions (e.g., angular positions), each of which may correspond to a corresponding operation of the material handling vehicle 100. For example, in the first (e.g., home) position 300, the brakes 116 of the material handling vehicle 100 may be applied to prevent forward movement of the vehicle. In some examples, in the first position 300, portions of the tiller arm 112 may be positioned substantially parallel to the vertical axis 228. Further, in some examples, the tiller arm 112 may be configured to automatically return to the first position 300 (and thus apply the brakes 116) if the operator releases the tiller arm 112. For example, a resilient member (e.g., a spring or other known resilient member) may bias the tiller arm 112 to the first position 300 (e.g., referred to as a deadman braking system). In some examples, when the tiller arm 112 is in the second position 304, the brakes 116 may be applied (e.g., similar to when in the first position 300). In some examples, in the second position 304 , the portion of the tiller arm 112 may be positioned substantially perpendicular to the vertical axis 228 .

[0042] In some examples, in addition to the first position 300 and the second position 304, the tiller arm 112 may also be movable between a plurality of control regions disposed between the first position 300 and the second position 304. For example, the tiller arm 112 may rotate between a first braking region 308, an operating region 312, and a second braking region 316. In some examples, the first braking region 308 may be disposed between the first position 300 and a first braking boundary 320 of the operating region 312. The operating region 312 may be disposed between the first braking boundary 320 and the second braking boundary 328. Accordingly, the second braking region 316 may be disposed between the second braking boundary 328 of the operating region 312 and the second position 304.

[0043] In some examples, the brakes 116 of the material handling vehicle 100 may be engaged when the tiller arm 112 is positioned within the first braking region 308 or the second braking region 316. Accordingly, when the tiller arm 112 is positioned within the operating region 312, the brakes 116 may be disengaged and the material handling vehicle 100 may be moved through the work area. In some examples, the operating region 312 may be larger than one or both of the first braking region 308 and the second braking region 316.

[0044] In some examples, the tiller arm 112 may also be movable between a first transition region 340 and a second transition region 344. The first transition region 340 and the second transition region 344 may be disposed within (e.g., as part of) the operating region 312, adjacent to the first braking boundary 320 and the second braking boundary 328, respectively. Specifically, the first transition region 340 and the second transition region 344 may extend from the first braking boundary 320 and the second braking boundary 328, respectively, into the operating region 312. In some examples, the feedback system 104 may be activated when the tiller arm 112 is within the first transition region 340 or the second transition region 344. For example, the feedback system may be activated to notify the operator that further movement of the tiller (e.g., toward the corresponding braking region) may activate the brakes 116 of the material handling vehicle 100. It should be appreciated that in some examples, the feedback system may be configured to notify the operator only when exiting the operating region 312 and entering the first moving region 308 or the second braking region 316, but may not notify the operator when entering the operating region 312 from the first moving region 308 or the second braking region 316.

[0045] Steering Figure 4-Figure 6 , the tiller detection system 128 may include a tiller arm 112 and one or more sensors 124. The one or more sensors 124 may determine the position (e.g., angular position) of the tiller arm 112 via the position of one or more cams of a cam assembly 425 at a first end 405 of the tiller arm 112. In some examples, the cam assembly 425 may include a first cam 220 and a second cam 224. The first cam 220 and the second cam 224 may be laterally spaced apart from each other such that each cam may correspond to a sensor 124. For example, the first cam 220 may correspond to the first sensor 700, and the second cam 224 may correspond to the second sensor 800. In some examples, the cams 220, 224 may each define different surface profiles that are configured to trigger the sensors 124 at different rotational positions.

[0046] For example, see Figure 5 , the first cam 220 may include a protrusion 504 (e.g., a single protrusion) that extends away from a surface 525 of the first cam 220 and defines a substantially arcuate surface profile. In some examples, the first cam 220 may be configured to interact with the first sensor 700 to indicate whether the tiller arm 112 is in the first braking region 308, the operating region 312, or the second braking region 316. Correspondingly, see Figure 6, the second cam 224 may include a pair of protrusions 616, 620 extending away from a surface 625 of the second cam 224. The protrusions 616, 620 may be separated from each other by a gap 635, which may correspond to the size of the protrusion 504 of the first cam 220. In some examples, the protrusions 616, 620 may be configured to interact with the second sensor 800 to indicate whether the tiller arm 112 is in the first transition region or the second transition region.

[0047] In some examples, the protrusions 616, 620 may be spaced apart such that when viewed from the side, the protrusion 504 may be disposed substantially between the protrusions 616, 620. Thus, during rotation of the tiller arm 112, when the protrusion 504 is about to leave the field of view of the sensor 124, the protrusions 616, 620 may be sensed by the sensor 124. Thus, when the sensor 124 senses one of the protrusions 616, 620, the feedback system may trigger a notification to alert the operator that further rotation of the tiller arm 112 may activate the brake.

[0048] In some examples, sensor 124 may be in the form of a switch or button that may be depressed or otherwise actuated by cams 220, 224 (e.g., during rotation of the cams). Sensor 124 may be in the form of a time-of-flight sensor, an infrared proximity sensor, a pressure sensor, an ultrasonic sensor, an inductive sensor, a Hall effect sensor, or any other known sensor.

[0049] refer to Figure 7-Figure 14 , illustrates an example operation of the tiller arm 112, with particular reference to the interaction between the cams 220, 224 and the sensors 700, 800 during operation (e.g., rotation) of the tiller arm 112. For example, during rotation of the tiller arm 112, the protrusions 504, 616, 620 extending from the cams 220, 224 may be sensed by the sensors 700, 800 to determine whether the tiller arm 112 is positioned within the operating region 312, the first braking region 308, the second braking region 316, the first transition region 340, or the second transition region 344.

[0050] like Figure 7-Figure 9 As illustrated, the first sensor 700 can be aligned with the first cam 220 and configured to sense the first protrusion 504 extending from the first cam 220. For example, the first sensor 700 can define a first sensing region 705 (e.g., a field of view) in which the first sensor 700 detects the presence of the first protrusion 504. In some examples, the detection of the first protrusion 504 within the first sensing region 705 can be used to determine whether the tiller arm 112 is in the first braking region 308, the second braking region 316, or the operating region 312.

[0051] For example, Figure 7 As shown, when the tiller arm 112 is in the first position 725 (e.g., the vertical position or the home position), the first sensor 700 may not detect the first protrusion 504. Therefore, the controller 120 may determine that the tiller arm is in the braking region 308 and may engage the brake 116. Fig. 9 As shown, when the tiller arm 112 is in the third position 925 (e.g., horizontal position), the first sensor 700 may not detect the first protrusion 504. Therefore, the controller may determine that the tiller arm is in the braking region 316 and may engage the brake 116. In another example, as shown in FIG. Figure 8 As shown, when the tiller arm 112 is in the second position 825, the first sensor 700 may detect the first protrusion 504. Therefore, the controller 120 may determine that the tiller arm 112 is in the operating region 312 and may disengage the brake 116 to allow movement of the material handling vehicle 100.

[0052] like Figure 10-Figure 14 As illustrated, the second sensor 800 may be aligned with the second cam 224 and configured to sense the second protrusion 616 and the third protrusion 620. For example, the second sensor 800 may define a second sensing region 805 (e.g., a field of view) in which the second sensor 800 detects the presence of the second protrusion 616 or the third protrusion 620. In some examples, the detection of the second protrusion 616 or the third protrusion 620 within the second sensing region may be utilized to determine whether the tiller arm 112 is within the first transition region 340 or the second transition region 344. Accordingly, the detection of the protrusions 616, 620 may engage the feedback system 104 to send feedback to the operator that the brake 116 may be applied upon further movement (e.g., rotation) of the tiller arm 112.

[0053] For example, Fig.10 As shown, when the second sensor 800 detects neither the second protrusion 616 nor the third protrusion 620, and the first sensor 700 detects the first protrusion 504, the controller 120 may determine that the tiller arm 112 is in the braking region 308 and may engage the brake 116. Fig.12 As shown, when the second sensor 800 does not detect the second protrusion 616 or the third protrusion 620, and the first sensor 700 does not detect the first protrusion 504, the controller 120 may determine that the tiller arm 112 is in the braking region 316 and may engage the brake 116. In another example, Fig.11As shown, when the second sensor 800 does not detect the second protrusion 616 or the third protrusion 620 , and the first sensor 700 detects the first protrusion 504 , the controller may determine that the tiller arm 112 is in the operating region 312 and may disengage the brake 116 to allow movement of the material handling vehicle 100 .

[0054] In some examples, such as Fig.13 As shown, in the fourth position 1325, the second sensor 800 detects the second protrusion 616 and the first sensor 700 detects the first protrusion 504. Therefore, the controller 120 can determine that the tiller arm 112 is in the first transition region 340 and the tiller arm 112 is about to enter the braking region 308. In some examples, the controller 120 can trigger the feedback system 104 to provide feedback to notify the operator that further movement of the tiller arm 112 can activate the brake 116. For example, the feedback system 104 can trigger audible, tactile, visual, or mechanical feedback.

[0055] Correspondingly, if Fig.14 As shown, in the fifth position 1425, the second sensor 800 detects the third protrusion 620 and the first sensor 700 detects the first protrusion 504. Therefore, the controller 120 can determine that the tiller arm 112 is in the second transition region 344 and the tiller arm 112 is about to enter the braking region 316. In some examples, the controller 120 can trigger the feedback system 104 to provide feedback to inform the operator that further movement of the tiller arm 112 can activate the brake 116. For example, the feedback system 104 can trigger audible, tactile, visual, or mechanical feedback.

[0056] It should be appreciated that in some examples, the feedback system 104 may be triggered only when the tiller arm 112 transitions from the operating region 312 into either of the braking regions 308, 316. Thus, the feedback system 104 may not be activated and may not provide feedback to the operator when the tiller arm 112 transitions from the braking regions 308, 316 into the operating region 312. In other words, the feedback system 104 may be unidirectionally operative, which may be useful in assisting the operator in understanding the operational boundaries of the tiller arm 112.

[0057] Figure 15-17 Another example of a tiller detection system 1500 is shown. As will be appreciated, the tiller detection system 1500 shares a number of common components with the previously illustrated and described examples (e.g., the tiller detection system 128) and operates in a similar manner thereto. For the sake of brevity, these common features will not be described in detail below. Instead, unless otherwise indicated, the previous discussion of commonly named or numbered features also applies to the example configuration of the tiller detection system 1500.

[0058] In some examples, the tiller detection system 1500 can utilize a pair of sensors instead of using a single second sensor 800 to sense the second cam 224. For example, each of the second protrusion 616 and the third protrusion 620 can include a corresponding sensor. For example, the second protrusion 616 can include the second sensor 1505, and the third protrusion 620 can include the third sensor 1510.

[0059] In some examples, such as Fig.15 As shown, when the second sensor 1505 detects the second protrusion 616, the controller 120 can determine that the tiller arm 112 is about to enter the braking area 308 (e.g., within the first transition area 340) and can trigger the feedback system 104 to provide feedback to notify the operator. For example, the feedback system 104 can trigger audible, tactile, visual, or mechanical feedback. Correspondingly, as Fig.17 As shown, when the third sensor 1510 detects the third protrusion 620, the controller 120 can determine that the tiller arm 112 is about to enter the braking area 316 (e.g., within the second transition area 344) and can trigger the feedback system 104 to provide feedback to notify the operator. For example, the feedback system 104 can trigger audible, tactile, visual, or mechanical feedback. In another example, Fig.16 As shown, when neither the second sensor 1505 nor the third sensor 1510 senses the corresponding second protrusion 616 or the third protrusion 620 , the feedback system 104 may not be triggered.

[0060] Figure 18-Figure 20 Another example of a tiller detection system 1800 is shown. As will be appreciated, the tiller detection system 1800 shares a number of common components with the previously illustrated and described examples (e.g., tiller detection systems 128, 1500) and operates in a similar manner thereto. For the sake of brevity, these common features will not be described in detail below. Instead, unless otherwise indicated, the previous discussion of commonly named or numbered features also applies to the example configuration of the tiller detection system 1800.

[0061] In one example, the tiller arm 112 may include a single cam 1805 (or a pair of cams) having the same surface profile, rather than including a pair of cams (e.g., cams 220, 224) having different surface profiles. The surface profile may include a protrusion 1810 and a pair of flanges 1815, 1820. In some examples, the flanges 1815, 1820 may be disposed on either side of the protrusion 1810. In use, the flanges 1815, 1820 may replace the protrusions 616, 620.

[0062] For example, Fig.18As shown, when the sensor 1825 does not detect the protrusion 1810 and does not detect either of the flanges 1815, 1820, the controller 120 can determine that the tiller arm 112 is in the braking region 316 and the brake 116 can be engaged. Fig.19 As shown, when the sensor 1825 does not detect the flanges 1815, 1820 but detects the protrusion 1810, the controller 120 can determine that the tiller arm 112 is in the operating area 312 and can disengage the brake 116 and allow operation of the material handling vehicle 100. In yet another example, as shown in FIG. Fig. 20 As shown, when the sensor 1825 does not detect the protrusion 1810 but detects one of the flanges 1815, 1820, the controller 120 can determine that the tiller arm 112 is about to enter the braking area 308, and can trigger the feedback system 104 to provide feedback to notify the operator while still allowing operation of the material handling vehicle 100. For example, the feedback system 104 can trigger audible, tactile, visual, or mechanical feedback.

[0063] In some implementations, methods that embody various aspects of the present invention may be used to utilize, manufacture, or install the devices or systems disclosed herein. Correspondingly, any description of a particular feature, capability, or intended purpose of a device or system herein is generally intended to include methods for disclosing the use of such devices for intended purposes, methods for otherwise realizing such capabilities, methods for manufacturing related components of such devices or systems (or devices or systems as a whole), and methods for installing disclosed (or otherwise known) components to support such purposes or capabilities. Similarly, unless otherwise indicated or limited, discussion of methods for any manufacture or use (including installation of the device or system) for a particular device or system herein is intended to inherently include the features used and capabilities realized by disclosing such devices or systems as embodiments of the present invention.

[0064] In addition, as used herein, unless otherwise limited or defined, "or" indicates a non-exclusive list of components or operations that can exist in any different combination, rather than an exclusive list of components that can only exist as alternatives to each other. For example, the list of "A, B, or C" indicates the following options: A; B; C; A and B; A and C; B and C; and A, B, and C. Correspondingly, the term "or" as used herein indicates exclusive alternatives only when preceded by an exclusive term, such as "any one," "one of...", "only one of...", or "exactly one of...". For example, the list of "one of A, B, or C" indicates the following options: A, but not B and C; B, but not A and C; and C, but not A and B. Lists of elements that begin with "one or more" (and variations thereof) and include "or" to separate the listed elements indicate the option of one or more of any or all of the listed elements. For example, the phrases "one or more of A, B, or C" and "at least one of A, B, or C" indicate the following options: one or more A; one or more B; one or more C; one or more A and one or more B; one or more B and one or more C; one or more A and one or more C; and one or more of A, one or more of B, and one or more of C. Similarly, a list beginning with "plurality" (and variations thereof) and including "or" to separate the listed elements indicates the option of multiple instances of any or all of the listed elements. For example, the phrases a plurality of "A, B, or C" and "two or more of A, B, or C" indicate the following options: A and B; B and C; A and C; and A, B, and C.

[0065] As used herein, unless otherwise limited or defined, "unitary" and its derivatives (e.g., "integrally") describe an element that is manufactured as a single piece without the need for fasteners, adhesives, etc. to secure the separate parts together. For example, an element that is stamped, cast, or otherwise molded as a single piece from a single sheet of sheet metal, or an element that uses a single mold without the need for rivets, screws, or adhesives to hold the separately formed pieces together is a unitary (and integrally formed) element. In contrast, an element formed from multiple pieces that are initially formed separately and then subsequently connected together is not a unitary (or integrally formed) element.

[0066] Unless otherwise limited or defined, "substantially parallel" refers to a direction within positive 12 degrees or negative 12 degrees (e.g., positive 6 degrees or negative 6 degrees or positive 3 degrees or negative 3 degrees) (including end values) of a reference direction. Correspondingly, "substantially vertical" refers to a direction substantially parallel to the vertical direction as defined relative to gravity, with a similar derivative meaning to "substantially horizontal" (relative to the horizontal direction). Similarly, unless otherwise limited or defined, "substantially perpendicular to" refers to a direction within positive 12 degrees or negative 12 degrees (e.g., positive 6 degrees or negative 6 degrees or positive 3 degrees or negative 3 degrees) (including end values) perpendicular to the reference direction.

[0067] Unless otherwise limited or defined, the terms "about" and "approximately" used herein with respect to a reference value refer to a variation of plus or minus 20% or less (e.g., plus or minus 15%, plus or minus 10%, plus or minus 5%, etc.) from the reference value, including the endpoints of the range. Similarly, the term "substantially equal" (and similar terms), as used herein with respect to a reference value, refers to a variation of less than plus or minus 5% (e.g., plus or minus 2%, plus or minus 1%, plus or minus 0.5% or minus 0.5%) (including the endpoints) from the reference value.

[0068] As used herein, unless otherwise defined or limited, any range of values ​​described as between a starting value and an ending value is defined to include the starting value and the ending value.

[0069] As used herein, unless otherwise defined or limited, directional terms are used for ease of reference to discuss a particular figure or example. For example, references to a downward (or other) direction or a top (or other) position may be used to discuss various aspects of a particular example or figure, but similar orientations or geometries are not necessarily required in all installations or configurations.

[0070] The previous description of the disclosed embodiments is provided to enable those skilled in the art to make or use the present disclosure. In view of the benefits of the present disclosure, various modifications to these embodiments will be apparent to those skilled in the art, and the principles defined herein may be applied to other embodiments without departing from the spirit or scope of the present disclosure. Thus, the present invention is not intended to be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A tiller arm detection system for a material handling vehicle, the tiller arm detection system comprising: Tiller arm, including: a cam assembly having a first cam with a first surface profile and a second cam with a second, different surface profile; a first sensor for detecting a portion of the first cam; a second sensor for detecting a portion of the second cam; and A controller for communicating with the first sensor and the second sensor to determine a position of the tiller arm based on the detected portion of the first cam or the second cam, and for activating a feedback system based on the detected portion of the first cam or the second cam.

2. The system of claim 1, wherein: The first cam includes a first protrusion defining the first surface profile.

3. The system of claim 2, wherein: The second cam includes a second protrusion and a third protrusion separated by a gap, the second protrusion, the third protrusion and the gap defining the second surface profile.

4. The system of claim 3, wherein the first cam is laterally offset from the second cam, and wherein the first cam is arranged such that the first protrusion of the first cam is substantially arranged within the gap formed between the second protrusion and the third protrusion of the second cam.

5. The system of claim 2, wherein: The controller determines that the tiller arm is in an operating region of the material handling vehicle when the first sensor detects the first protrusion of the first cam.

6. The system of claim 2, wherein: The controller determines that the tiller arm is in a braking region of the material handling vehicle when the first sensor does not detect the first protrusion of the first cam.

7. The system of claim 3, wherein: The controller determines that the tiller arm is in a transition region when the second sensor detects the second protrusion or the third protrusion of the second cam.

8. The system of claim 7, wherein: When the controller determines that the tiller arm is in the transition region, the controller activates the feedback system to provide feedback to an operator of the material handling vehicle.

9. The system of claim 8, wherein: The feedback is audible, tactile, visual or mechanical feedback.

10. The system of claim 8, wherein: The feedback system is activated when the tiller arm moves from the operating area to the transition area and is not activated when the tiller arm moves from the braking area to the transition area.

11. A method of providing feedback to an operator of a material handling vehicle, the method comprising: detecting, via a first sensor, a first cam of a cam assembly disposed at an end of a tiller arm of the material handling vehicle, the first cam defining a first surface profile; detecting, via a second sensor, a second cam of the cam assembly, the second cam defining a second, different surface profile; determining a position of the tiller arm via a controller in communication with the first sensor and the second sensor; as well as Based on the position of the tiller arm, a feedback system of the material handling vehicle is activated to provide feedback to an operator corresponding to the position of the tiller arm.

12. The method of claim 11, wherein: The first cam includes a first protrusion defining the first surface profile.

13. The method of claim 12, wherein: The second cam includes a second protrusion and a third protrusion separated by a gap, the second protrusion, the third protrusion and the gap defining the second surface profile.

14. The method of claim 13, further comprising: When the second sensor detects the second protrusion or the third protrusion of the second cam and the first sensor detects the first protrusion of the first cam, it is determined that the tiller arm is in a transition region.

15. The method of claim 14, further comprising: When the tiller arm is in the transition region, the feedback system is activated to provide feedback to an operator of the materials handling vehicle.

16. A tiller arm for a material handling vehicle, the tiller arm comprising: Cam assembly, comprising: a first cam having a first protrusion defining a first surface profile; and a second cam disposed substantially parallel to and laterally spaced from the first cam, the second cam having a second protrusion and a third protrusion separated by a gap, the second protrusion, the third protrusion, and the gap defining a second surface profile; The first cam is arranged such that the first protrusion of the first cam is substantially arranged within the gap formed between the second protrusion and the third protrusion of the second cam.

17. The tiller arm of claim 16, wherein: The first sensor is configured to detect the first protrusion of the first cam, and wherein the second sensor is configured to detect the second protrusion or the third protrusion of the second cam.

18. The tiller arm of claim 17, wherein: A controller communicates with the first sensor and the second sensor to determine a position of the tiller arm based on detection of the first protrusion of the first cam or the second protrusion or the third protrusion of the second cam.

19. The tiller arm of claim 18, wherein: The controller activates a feedback system of the material handling vehicle based on detection of the second protrusion or the third protrusion of the second cam.

20. The tiller arm of claim 19, wherein: The feedback from the feedback system is audible, tactile, visual or mechanical feedback.

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