CN114761350A

CN114761350A - Resetting stored data relating to monitored driving parameters based on a detected initiation of a picking operation

Info

Publication number: CN114761350A
Application number: CN202180006985.7A
Authority: CN
Inventors: A·西蒙; S·西欧斯; J·纳驰提加尔
Original assignee: Crown Equipment Corp
Current assignee: Crown Equipment Corp
Priority date: 2020-03-18
Filing date: 2021-03-15
Publication date: 2022-07-15
Also published as: EP4121386B1; CA3161726A1; AU2021239825A1; KR20220155314A; WO2021188402A1; MX2022006498A; EP4121386A1

Abstract

A method for operating a materials handling vehicle is provided, the method comprising: monitoring, by a controller, a first vehicle driving parameter during manual operation of the vehicle by an operator; data relating to the monitored first vehicle driving parameter is stored by the controller. The controller is configured to enable semi-autonomous driving operation of the vehicle using the stored data after manual operation of the vehicle. The method further comprises the following steps: detecting, by the controller, an operation of the vehicle indicating a start of a picking operation occurring during a manual operation of the vehicle; and resetting, by the controller, stored data relating to the monitored first vehicle driving parameter based on detecting the start of the picking operation.

Description

Resetting stored data relating to monitored driving parameters based on a detected initiation of a picking operation

Background

Materials handling vehicles are commonly used to pick-up goods at warehouses and distribution centers. Such vehicles typically include a power unit and a load handling assembly, which may include load carrying forks. The vehicle also has a control structure for controlling operation and movement of the vehicle.

In a typical picking operation, an operator fills an order from available inventory items located in a storage area provided along one or more aisles of a warehouse or distribution center. The operator drives the vehicle between various picking locations for the item(s) to be picked. The operator may drive the vehicle either by using control structures on the vehicle or via a wireless remote control device associated with the vehicle.

Disclosure of Invention

The present disclosure relates to a method for operating a materials handling vehicle, the method comprising monitoring, by a controller, a first vehicle driving parameter during manual operation of the vehicle by an operator; storing, by a controller, data relating to the monitored first vehicle driving parameter, the controller configured to effect semi-autonomous driving operation of the vehicle using the stored data following manual operation of the vehicle; detecting, by the controller, an operation of the vehicle indicating a start of a picking operation occurring during a manual operation of the vehicle; and resetting, by the controller, stored data relating to the monitored first vehicle driving parameter based on detecting the start of the picking operation.

The method according to embodiments disclosed herein further includes resuming monitoring of the first vehicle driving parameter by the controller after resetting the stored data.

According to embodiments disclosed herein, the detected operation of the vehicle comprises a transition from the vehicle being manually driven with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered. Further, the elevated load handling assembly may bear a substantially non-zero load and the lowered load handling assembly may bear a substantially zero load.

According to embodiments disclosed herein, the load handling assembly may include one or more forks, and the detected operation of the vehicle further includes movement of the vehicle a distance that may be at least equal to the length of the load carried by the forks. In particular, movement of the vehicle for a distance at least equal to the length of the load carried by the forks occurs after the vehicle transitions to being stopped with the lowered load handling assembly.

According to any of the above embodiments, the detected operation of the vehicle further comprises driving the vehicle with the lowered load handling assembly. In particular, the lowered load handling assembly may be subjected to substantially zero load.

According to embodiments disclosed herein, the detected operation of the vehicle further comprises a transition from the vehicle moving with the load handling assembly lowered to the vehicle being stopped with the load handling assembly subsequently raised, wherein the subsequently raised load handling assembly is subjected to a load less than a predetermined amount but greater than substantially zero load. Such loads less than a predetermined amount but greater than a substantially zero load may comprise, for example, substantially empty pallets on the load handling assembly.

According to embodiments disclosed herein, the detected operation of the vehicle comprises a first transition from the vehicle being manually driven with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered; the vehicle, with the load handling assembly lowered, moving by a distance at least equal to the length of the load carried by the load handling assembly, the moving occurring after the first transition; and a second transition from the vehicle moving with the load handling assembly lowered to the vehicle stopped with the load handling assembly newly raised. In particular, during the second transition, the lowered load handling assembly is subjected to substantially zero load and the newly raised load handling assembly is subjected to a load less than a predetermined amount but greater than substantially zero.

According to embodiments disclosed herein, the method may include monitoring, by the controller, a second vehicle driving parameter during manual operation of the vehicle by the operator; and storing, by a controller, data relating to the monitored second vehicle driving parameter, the controller configured to effect semi-autonomous driving operation of the vehicle using the stored data of the monitored first and second vehicle driving parameters following manual operation of the vehicle.

In accordance with embodiments disclosed herein, a system for operating a materials handling vehicle comprises a memory storing executable instructions; and a processor in communication with the memory. In particular, execution of the executable instructions by the processor causes the processor to: monitoring a first vehicle driving parameter during manual operation of the vehicle by an operator; storing data relating to the monitored first vehicle driving parameter, the controller being configured to effect semi-autonomous driving operation of the vehicle using the stored data following manual operation of the vehicle; detecting operation of the vehicle indicating a start of a picking operation occurring during manual operation of the vehicle; and resetting the stored data relating to the monitored first vehicle driving parameter based on detecting the start of the picking operation.

The system also includes a processor that resumes monitoring of the first vehicle driving parameter after resetting the stored data.

According to embodiments disclosed herein, the detected vehicle operation includes a transition from the vehicle being manually driven with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered. Further, the elevated load handling assembly may bear a substantially non-zero load and the lowered load handling assembly may bear a substantially zero load.

According to embodiments disclosed herein, the detected operation of the vehicle further comprises driving the vehicle with the lowered load handling assembly. In particular, the lowered load handling assembly may be subjected to substantially zero load.

According to embodiments disclosed herein, the detected operation of the vehicle further comprises a transition from the vehicle moving with the load handling assembly lowered to the vehicle being stopped with the load handling assembly subsequently raised, wherein the subsequently raised load handling assembly is subjected to a load less than a predetermined amount but greater than substantially zero load.

According to embodiments disclosed herein, the detected operation of the vehicle comprises a first transition from the vehicle being manually driven with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered; the vehicle, with the load handling assembly lowered, moving by a distance at least equal to the length of the load carried by the load handling assembly, the moving occurring after the first transition; and a second transition from the vehicle moving with the load handling assembly lowered to the vehicle stopped with the load handling assembly newly raised. In particular, during the second transition, the lowered load handling assembly is subjected to a substantially zero load and the newly raised load handling assembly is subjected to a load less than a predetermined amount but greater than the substantially zero load.

According to embodiments disclosed herein, the system may include a processor that monitors a second vehicle driving parameter during manual operation of the vehicle by the operator; and storing data relating to the monitored second vehicle driving parameter, wherein the processor is configured to effect semi-autonomous driving operation of the vehicle using the stored data of the monitored first and second vehicle driving parameters following manual operation of the vehicle.

Drawings

FIGS. 1A and 1B are diagrammatic views of a materials handling vehicle capable of remote wireless operation according to one or more embodiments shown and described herein;

FIG. 2 is a schematic diagram of several components of a materials handling vehicle capable of remote wireless operation according to one or more embodiments shown and described herein;

FIG. 3 depicts a flowchart of an example algorithm for monitoring first and second driving parameters during a most recent manual operation of a vehicle and controlling implementation of a semi-autonomous driving operation based on the first and second driving parameters, according to one or more embodiments shown and described herein;

FIG. 4 depicts a flowchart of an example algorithm for calculating a first value indicative of acceleration of a vehicle in a first direction during a most recent manual operation of the vehicle, according to one or more embodiments shown and described herein;

FIG. 5 illustrates a table containing unrealistic sample acceleration values in a first direction corresponding to a most recent manual operation of a vehicle, in accordance with one or more embodiments shown and described herein;

FIG. 6 illustrates a graph containing wa according to one or more embodiments shown and described herein_x-iA table of sample values of;

FIG. 7 depicts a flowchart of an example algorithm for calculating a second value indicative of acceleration of the vehicle in a second direction during a most recent manual operation of the vehicle in accordance with one or more embodiments shown and described herein;

FIG. 8 illustrates a table containing unrealistic sample acceleration values in a second direction corresponding to a most recent manual operation of a vehicle, in accordance with one or more embodiments shown and described herein;

FIG. 9 illustrates an enclosure wa according to one or more embodiments shown and described herein_y-A table of sample values of i;

FIG. 10 depicts a flowchart of an example algorithm for calculating a maximum acceleration to be used during a next semi-autonomous driving operation based on first and second values indicative of acceleration of the vehicle in first and second directions during a previous manual operation of the vehicle, according to one or more embodiments shown and described herein;

FIG. 11 depicts a maximum acceleration (a) included in a second direction according to one or more embodiments shown and described herein_ywa-max) III of (2)A look-up table of individual ranges;

FIG. 12 depicts a flowchart of an example algorithm for resetting stored data related to monitored first vehicle driving parameters based on detecting the beginning of a picking operation, according to one or more embodiments shown and described herein; and

13-15 depict a vehicle operation sequence indicating the start of a picking operation during manual operation of the vehicle in accordance with one or more embodiments shown and described herein.

Detailed Description

In the following detailed description of the illustrated embodiments, reference is made to the accompanying drawings that form a part hereof, and in which is shown by way of illustration, and not by way of limitation, specific embodiments that may be practiced. It is to be understood that other embodiments may be utilized and that changes may be made without departing from the spirit and scope of the various embodiments of the present disclosure.

Low-grade electric material-picking truck

Referring now to the drawings, and more particularly to fig. 1A and 1B, a materials handling vehicle, illustrated as a low level order picking truck (10), generally includes a load handling assembly 12 extending from a power unit 14. The load handling assembly 12 includes a pair of forks 16, each fork 16 having a load support wheel assembly 18. In addition to or in lieu of the illustrated arrangement of the forks 16, the load handling assembly 12 may include other load handling features, such as load backs (load backs), scissor-type lifting forks (scissors-type lifting forks), outriggers, or separate height adjustable forks. Still further, the load handling assembly 12 may include load handling features such as a mast, a load platform, a collection cage, or other support structure carried by the forks 16 or otherwise provided for handling a load supported and carried by the truck 10 or pushed or pulled by the truck (i.e., such as by a trailer).

The illustrated power unit 14 includes a step-through operator's station 30 that separates a first end section 14A (opposite the forks 16) from a second end section 14B (adjacent the forks 16) of the power unit 14. The walk-in operator station 30 provides a platform 32 on which an operator may stand to drive the truck 10 and/or to provide a location where the operator may operate various included features of the truck 10.

The first work area is disposed toward the first end section 14A of the power unit 14 and includes a control area 40 for driving the truck 10 when an operator is standing on the platform 32 and for controlling features of the load handling assembly 12. The first end section 14A defines a compartment 48 for housing batteries, control electronics, including a controller 103 (see fig. 2), and motor(s), such as a traction motor, a steering motor, and a lift motor (not shown) for the forks.

As shown for purposes of illustration and not limitation, the control zone 40 includes a handle 52 for steering the truck 10, which may include controls such as a handlebar, butterfly switch, thumb wheel, rocker switch, hand wheel, steering tiller, etc., for controlling acceleration/braking and direction of travel of the truck 10, see fig. 1A and 1B. For example, as shown, a control such as a switch handle or travel switch 54 may be provided on a handle 52, the handle 52 being spring biased to a center neutral position. Rotating the travel switch 54 forward and upward will cause the truck 10 to move forward with an acceleration proportional to the amount of rotation of the travel switch 54, e.g., first the power unit, until the truck 10 reaches a predefined maximum speed at which time the truck 10 is no longer allowed to accelerate to a higher speed. For example, if the travel switch 54 is rotated very quickly 50% of the maximum angle the handle 54 can be rotated, the truck 10 will accelerate at about 50% of the maximum acceleration the truck can reach until the truck reaches 50% of the maximum speed the truck can reach. It is also contemplated that the acceleration may be determined using an acceleration map stored in memory, where the rotational angle of the handlebar 54 is used as an input in the acceleration map and has a corresponding acceleration value in the acceleration map. The acceleration value in the acceleration map corresponding to the handle rotation angle may vary in proportion to the handle rotation angle or in any desired manner. There may also be a velocity map stored in memory, where the angle of rotation of the handle 54 is used as an input in the velocity map and has a corresponding maximum velocity value stored in the velocity map. For example, when the handle 54 is rotated 50% of the maximum angle the handle 54 can be, the truck will accelerate with the corresponding acceleration value stored in the acceleration map to the maximum speed value corresponding to a handle angle of 50% of the maximum angle stored in the speed map. Similarly, rotating the travel switch 54 toward the rear of the truck 10 and downward will cause the truck 10 to move in reverse at an acceleration that is proportional to the amount of rotation of the travel switch 54, e.g., first the forks, until the truck 10 reaches a predefined maximum speed that corresponds to the amount of rotation of the travel switch 54, at which time the truck 10 is no longer allowed to accelerate to a higher speed.

A presence sensor 58 may be provided to detect the presence of an operator on the truck 10. For example, the presence sensors 58 may be located above, or below the platform floor, or otherwise provided around the operator station 30. In the exemplary truck 10 of fig. 1, the presence sensors 58 are shown in phantom lines indicating that they are located under the platform floor. In such an arrangement, the presence sensor 58 may include a load sensor, a switch, or the like. Alternatively, the presence sensors 58 may be implemented above the platform floor, such as by using ultrasonic, capacitive, laser scanners, cameras, or other suitable sensing technology. The use of the presence sensor 58 will be described in more detail herein.

An antenna 66 extends vertically from the power unit 14 and is provided for receiving control signals from a corresponding wireless remote control device 70. It is also contemplated that the antenna 66 may be disposed within the compartment 48 of the power unit 14 or elsewhere on the truck 10. According to one embodiment, the truck 10 may include a mast (not shown) extending vertically from the power unit 14 and including an antenna 66, the antenna 66 being provided for receiving control signals from a corresponding wireless remote control device 70. The pole may include a light at the top, such that the pole and light define a lighthouse. The remote control device 70 may include a transmitter worn or otherwise maintained by the operator. The remote control device 70 may be manually operated by the operator, for example, by pressing a button or other control, to cause the remote control device 70 to wirelessly transmit at least a first type of signal specifying a travel request to the truck 10. The travel request is a command requesting that the corresponding truck 10 travel a predetermined amount, as will be described in greater detail herein.

The truck 10 also includes one or more obstacle sensors 76 disposed about the truck 10, for example, toward the first end section of the power unit 14 and/or the side of the power unit 14. The obstacle sensors 76 include at least one non-contact obstacle sensor on the truck 10 and are operable to define at least one detection zone. For example, when the truck 10 is traveling in response to a travel request received wirelessly from the remote control device 70, the at least one detection zone may define an area at least partially in front of the forward travel direction of the truck 10.

The obstacle sensors 76 may include any suitable proximity detection technology, such as ultrasonic sensors, optical recognition devices, infrared sensors, laser scanner sensors, etc., capable of detecting the presence of objects/obstacles or capable of generating signals that may be analyzed to detect the presence of objects/obstacles within the predefined detection zone(s) of the power unit 14.

In practice, the truck 10 may be implemented in other formats, styles, and features, such as an end control tray truck that includes a steering tiller arm coupled to a tiller for steering the truck. Similarly, while the remote control device 70 is illustrated as a glove-like structure 70, various embodiments of the remote control device 70 may be implemented, including, for example, finger wear, lanyard or belt mounting, and the like. Still further, the truck, the remote control system, and/or components thereof, including the remote control device 70, may include any additional and/or alternative features or embodiments.

Remotely operated control system for low grade order picking truck

Referring to fig. 2, a block diagram illustrates a control arrangement for integrating remote control commands with the truck 10. Antenna 66 is coupled to receiver 102 for receiving instructions issued by remote control device 70. The receiver 102 passes the received control signals to the controller 103, and the controller 103 implements the appropriate responses to the received commands, and thus may also be referred to herein as a master controller. In this regard, the controller 103 is implemented in hardware and may also execute software (including firmware, resident software, micro-code, etc.). Furthermore, embodiments may take the form of a computer program product embodied in one or more computer-readable media having computer-readable program code embodied thereon.

Thus, the controller 103 may comprise an electronic controller defining, at least in part, a data processing system suitable for storing and/or executing program code, and may include at least one processor coupled directly or indirectly to memory elements, e.g., through a system bus or other suitable connection. The memory elements can include local memory employed during actual execution of the program code, memory integrated into a microcontroller or Application Specific Integrated Circuit (ASIC), programmable gate arrays or other reconfigurable processing devices, and so forth. The at least one processor may include any processing element operable to receive and execute executable instructions, such as program code from one or more memory elements. The at least one processor may comprise any type of device that receives input data, processes the data through computer instructions, and generates output data. Such a processor may be a microcontroller, handheld device, laptop or notebook computer, desktop computer, mini computer, Digital Signal Processor (DSP), mainframe, server, cellular telephone, personal digital assistant, other programmable computer device, or any combination thereof. Such a processor may also be implemented using programmable logic devices such as Field Programmable Gate Arrays (FPGAs), or alternatively as an Application Specific Integrated Circuit (ASIC), or similar device. The term "processor" is also intended to encompass a combination of two or more of the above devices, e.g., two or more microcontrollers.

Depending on the logic implemented, the response implemented by the controller 103 in response to a command received wirelessly, e.g., via the wireless transmitter and corresponding antenna 66 and receiver 102 of the remote control device 70, may include one or more actions or no actions. The positive (positive) action may include controlling, adjusting, or otherwise affecting one or more components of the truck 10. The controller 103 may also receive information from other inputs 104, for example, from sources such as the presence sensors 58, the obstacle sensors 76, switches, load sensors, encoders and other devices/features available to the truck 10 to determine appropriate actions to take in response to commands received from the remote control device 70. The

sensors

58, 76, etc. may be coupled to the controller 103 via the input 104 or via a suitable truck network, such as a Control Area Network (CAN) bus 110.

A further input to the controller 103 may be a weight signal generated by a load sensor LS (such as a conventional pressure transducer, see fig. 2) that senses the combined weight of the forks 16 and any load on the forks 16. The load sensor LS may be incorporated into the hydraulic system to effect the lifting of the forks 16. The controller 103 determines the weight of the load L on the forks 16 by subtracting the weight of the forks 16 (a known constant value) from the combined weight of the forks 16 and the load L on the forks 16, which combined weight is defined by the weight signal from the load sensor LS. Alternatively, instead of the pressure transducer LS being incorporated into the hydraulic system, one or more weight sensing units (not shown) may be integrated into the forks 16 to sense the load L on the forks 16 and generate corresponding load sensing signals to the controller 103.

The controller 103 is also capable of determining the vertical position, i.e., height, of the load handling assembly 12, including the forks 16, relative to a ground surface, such as a floor surface along which the truck 10 travels, as described below. One or more height sensors or switches may be provided in the second end section 14B of the power unit 14 that sense when the load handling assembly 12, including the forks 16, is vertically elevated relative to the ground and/or a lower point on the first end section 14A of the power unit 14. For example, first, second and third switches (not shown) may be provided within the second end section 14B at first, second and third vertical positions designated by dashed

lines

141A, 141B and 141C in fig. 1A, which switches are actuated when the load handling assembly 12 is raised. The lowest position of the load handling assembly 12 may also be determined via a load sensor LS indicating zero weight.

In one embodiment, the controller 103 may include one or more accelerometers that may measure the physical acceleration of the truck 10 along one, two, or three axes. It is also contemplated that the accelerometer 1103 may be separate from the controller 103 but coupled to and in communication with the controller 103 to generate and transmit an acceleration signal to the controller 103, see fig. 2. For example, the accelerometer 1103 may measure an acceleration of the truck 10 in a direction of travel DT (also referred to herein as a first direction of travel) of the truck 10, which in the embodiment of fig. 1 is collinear with an axis X, which may be generally parallel with the forks 16. The direction of travel DT or first direction of travel may be defined as the direction in which the truck 10 is moving, and may be a forward or power unit first direction, or a reverse or fork first direction. The accelerometer 1103 may also measure the acceleration of the truck 10 in a lateral direction TR (also referred to herein as a second direction) that is approximately 90 degrees to the direction of travel DT of the truck 10, which in the embodiment of fig. 1 is collinear with the Y-axis. The accelerometer 1103 may also measure acceleration of the truck 10 in another direction, generally collinear with the Z-axis, transverse to both the direction of travel DT and the transverse direction TR.

In the exemplary arrangement, the remote control device 70 is operable to wirelessly transmit a control signal, such as a travel command, representative of a first type of signal to a receiver 102 on the truck 10. The travel command is also referred to herein as a "travel signal," travel request, "or" travel signal. The travel request is used to initiate a request to travel the truck 10 a predetermined amount, for example, such that the truck 10 generally only advances or crawls a limited travel distance in the power unit first direction. The limited travel distance may be defined by an approximate travel distance, travel time, or other measure. In one embodiment, the truck may be driven continuously as long as the duration of the operator-provided travel request does not exceed a predetermined amount of time, such as 20 seconds. After the operator no longer provides the travel request, or if the travel request is provided for more than a predetermined period of time, the traction motors that affect the movement of the truck are no longer activated and the truck is allowed to coast to a stop. Truck 10 may be controlled to travel in a generally straight direction or along a previously determined heading.

Accordingly, the first type signal received by the receiver 102 is transmitted to the controller 103. If the controller 103 determines that the travel signal is a valid travel signal and that the current vehicle conditions are appropriate (explained in more detail below), the controller 103 sends a signal to the appropriate control configuration for the particular truck 10 to proceed and then stops the truck 10. For example, stopping of the truck 10 may be accomplished by allowing the truck 10 to coast to a stop or by initiating a braking operation to brake the truck 10 to a stop.

As an example, the controller 103 may be communicatively coupled to a traction control system, illustrated as a traction motor controller 106 of the truck 10. The traction motor controller 106 is coupled to a traction motor 107 that drives at least one driven wheel 108 of the truck 10. The controller 103 may communicate with the traction motor controller 106 to accelerate, decelerate, adjust, and/or otherwise limit the speed of the truck 10 in response to receiving a travel request from the remote control device 70. The controller 103 may also be communicatively coupled to a steering controller 112, the steering controller 112 being coupled to a steering motor 114, the steering motor 114 steering at least one steered wheel 108 of the truck 10, where the steered wheel may be different from the driven wheel. In this regard, the truck 10 may be controlled by the controller 103 to either drive a desired path or maintain a desired heading in response to receiving a drive request from the remote control device 70.

The controller 103 may determine whether the truck 10 is moving or stopped and the straight-line distance the truck 10 has traveled as follows. First, the controller 103 may use the signal generated by the accelerometer 1103 and integrate once to determine whether the truck 10 is moving or stopped. It may also be determined whether truck 10 is moving by determining whether the current value from accelerometer 1103 is greater than zero. The controller 103 may also use the signal generated by the accelerometer 1103 and integrate twice to determine the straight-line distance the truck 10 has traveled. Alternatively, the traction controller 106 may receive feedback signals generated by encoders within the traction motors 107 and generate motor angular velocity signals to the controller 103 from these signals. The controller 103 may determine whether the vehicle is moving or stopped based on the motor angular velocity signal. The controller 103 may also convert the motor angular velocity signal to the actual linear velocity of the truck 10. For example, if the speed signal includes the angular speed of the traction motor 107, the controller 103 may scale the value to the actual linear speed of the vehicle 10 based on a) a gear ratio (gearing ratio) between the traction motor 107 and the driven wheels of the vehicle, and b) the circumference of the driven wheels. The linear velocity of the vehicle (via integration) may then be used to determine the distance the truck 10 has traveled.

As yet another illustrative example, the controller 103 may also communicate with the traction controller 106 to slow, stop, or otherwise control the speed of the truck 10 in response to receiving a travel request from the remote control device 70. Braking may be accomplished by the traction controller 106 by causing regenerative braking or activating a mechanical brake 117 coupled to the traction motor 107, see fig. 2. Still further, the controller 103 may be communicatively coupled to other vehicle features, such as the main contactors 118, and/or other outputs 119 associated with the truck 10, as applicable, to implement desired actions in response to implementing the remote travel function.

According to an embodiment, the controller 103 may communicate with the receiver 102 and with the traction controller 106 to operate the truck 10 under remote control in response to receiving a travel command from an associated remote control device 70.

Correspondingly, if the truck 10 is moving in response to a command received by the remote wireless control, the controller 103 may dynamically alter, control, adjust, or otherwise affect the remote control operation, for example, by stopping the truck 10, changing the steering angle of the truck 10, or taking other actions. Thus, the manner in which the controller 103 responds to travel requests from the remote control device 70 may be affected by the particular vehicle feature, the state/condition of one or more vehicle features, the vehicle environment, and the like.

The controller 103 may refuse to acknowledge a received travel request depending on predetermined condition(s), e.g., relating to the environment or operating factor(s). For example, the controller 103 may ignore otherwise valid travel requests based on information obtained from one or more of the

sensors

58, 76. By way of illustration, according to an embodiment, the controller 103 may optionally consider factors such as whether the operator is on the truck 10 when determining whether to respond to a travel command from the remote control device 70. As described above, the truck 10 may include at least one presence sensor 58 for detecting whether an operator is located on the truck 10. In this regard, the controller 103 may also be configured to respond to a travel request to operate the truck 10 under remote control when the presence sensor(s) 58 indicate that no operator is present on the truck 10. Thus, in such embodiments, the truck 10 cannot be operated in response to a wireless command from the transmitter unless the operator physically leaves the truck 10. Similarly, if the object sensor 76 detects that an object, including the operator, is adjacent to and/or proximate to the truck 10, the controller 103 may refuse to acknowledge the travel request from the transmitter 70. Thus, in an exemplary embodiment, the operator must be within a limited range of the truck 10, for example, close enough to the truck 10 to be within wireless communication range (which may be limited to setting the operator's maximum distance from the truck 10). Other arrangements may alternatively be implemented.

Any other number of reasonable conditions, factors, parameters, or other considerations may also/alternatively be implemented by the controller 103 to interpret and take action in response to signals received from the transmitter.

Upon confirmation of the travel request, the controller 103 interacts, e.g., directly or indirectly, with the traction motor controller 106, e.g., via a bus such as the CAN bus 110 (if used), to advance the truck 10 a limited amount. Depending on the particular implementation, the controller 103 may interact with the traction motor controller 106 and optionally the steering controller 112 to advance the truck 10 a predetermined distance. Alternatively, the controller 103 may interact with the traction motor controller 106 and optionally the steering controller 112 to advance the truck 10 for a period of time in response to detecting and maintaining actuation of travel controls on the remote control device 70. As yet another illustrative example, the truck 10 may be configured to jog as long as the travel control signal is received. Still further, the controller 103 may be configured to "time out" and stop travel of the truck 10 based on a predetermined event, such as exceeding a predetermined time period or travel distance, regardless of whether a maintained actuation of a corresponding control on the remote control device 70 is detected.

The remote control device 70 is also operable to transmit a second type of signal, such as a "stop signal," indicating that the truck 10 should be braked and/or otherwise stationary. The second type of signal may also be implied under remote control in response to a travel command, e.g., after a "travel" command is implemented, e.g., after truck 10 has traveled a predetermined distance, traveled a predetermined time, etc. If the controller 103 determines that the wirelessly received signal is a stop signal, the controller 103 sends a signal to the traction controller 106 and/or other truck components to bring the truck 10 to rest. As an alternative to a stop signal, the second type of signal may include a "coast signal" or a "controlled deceleration signal" indicating that the truck 10 should coast, eventually decelerating to rest.

The time required to bring the truck 10 completely stationary may vary depending on, for example, the intended application, environmental conditions, the capabilities of a particular truck 10, the load on the truck 10, and other similar factors. For example, after completing a proper jog movement, it may be desirable to allow the truck 10 to "coast" a distance before coming to rest, so that the truck 10 comes to a slow stop. This may be accomplished by decelerating truck 10 to a stop using regenerative braking. Alternatively, the braking operation may be applied after a predetermined delay time to allow the truck 10 to additionally travel a predetermined range after initiation of the stopping operation. For example, it may also be desirable to stop the truck 10 relatively faster if an object is detected in the travel path of the truck 10 or if an immediate stop is desired after a successful jog operation. For example, the controller may apply a predetermined torque to the braking operation. In this case, the controller 103 may instruct the traction controller 106 to brake via regenerative braking or applying the mechanical brakes 117 to stop the truck 10.

Calculating vehicle driving parameter(s) used during vehicle remote control operation

As described above, an operator may stand on platform 32 within operator station 30 to manually operate truck 10, i.e., operate the truck in a manual mode. The operator may maneuver the truck 10 via the handle 52, see fig. 1B, and further, may accelerate the truck 10 via rotation of the travel switch 54. As also discussed above, rotating the travel switch 54 forward and upward will cause the truck 10 to move forward with an acceleration proportional to the amount of rotation of the travel switch 54, e.g., first the power unit. Similarly, rotating the travel switch 54 toward the rear of the truck 10 and downward will cause the truck 10 to move in reverse at an acceleration that may be proportional to the amount of rotation of the travel switch 54, e.g., first the forks. Rotating the travel switch 54 forward and upward will cause the truck 10 to brake when the truck 10 is moving in the fork first direction. Further, rotating the travel switch 54 rearward and downward will cause the truck 10 to brake when the truck 10 is moving in the power unit first direction. Thus, an "operator manual operation of the vehicle" occurs when an operator is standing on the platform 32 within the operator's station 30 and manipulating the truck 10 via the handle 52 and accelerating/braking (i.e., regenerative braking) the truck via rotation of the travel switch 54. The operator may use a separate brake switch, such as switch 41 of FIG. 1B, to cause regenerative braking of truck 10. As mentioned above, braking may also be achieved via mechanical brake 117.

As also described above, the controller 103 may communicate with the receiver 102 and the traction controller 106 to operate the truck 10 under remote control in response to receiving a travel command from an associated remote control device 70. The travel request is used to initiate a request to the truck 10 to travel a predetermined amount, for example, to advance or jog the truck 10 a limited travel distance in a first travel direction, i.e., in a power unit first direction. Thus, when the operator is not physically on the truck but is walking near the truck 10, such as during a picking operation, the operator may operate the truck 10 in a remote control mode, i.e., using the remote control device 70 to operate the truck 10 under remote control when the operator is located outside of the truck 10 and picks or collects picked items from a warehouse storage area to be loaded onto the truck 10. Operating truck 10 in a remote control mode is also referred to herein as "semi-autonomous" operation of truck 10.

When the operator is using the truck 10, such as during a picking operation in a warehouse, the operator typically uses the truck 10 in both a manual mode and a remote control mode.

Previously, vehicle controllers stored predefined, fixed vehicle parameters, such as maximum acceleration, to limit the maximum acceleration of the vehicle during operation of the vehicle in a remote control mode. This predefined maximum acceleration limit is sometimes too high (e.g. if the truck is loaded with a large pile of items/packages defining an unstable load) and sometimes too low (if the truck is loaded with a small pile of items/packages defining a stable load).

According to an embodiment of the present disclosure, the controller 103 monitors one or more driving parameters during the most recent manual operation of the truck 10 that correspond to a driving behavior or trait of an operator of the truck 10. If one or more of the driving parameters are high, this may correspond to the operator driving the truck 10 lightly. If one or more of the driving parameters are low, this may correspond to the operator driving the truck 10 conservatively or cautiously. Instead of using one or more predefined fixed driving parameters for vehicle control during remote control operation of the truck 10, the controller 103 calculates one or more adaptive driving parameters for use during the next remote control operation of the truck 10 based on one or more driving parameters monitored during the most recent manual operation of the truck 10. Since calculating the one or more driving parameters for the next remote control operation of the truck 10 is based on the operator's recent driving behavior, i.e., the one or more driving parameters monitored during the most recent manual mode operation of the truck 10, it is believed that the controller 103 more accurately and appropriately defines the one or more driving parameters to be used during the next remote control operation of the truck 10 such that the one or more driving parameters more closely match the operator's recent driving behavior.

An example control algorithm or process of the controller 103 is illustrated in fig. 3 for monitoring first and second driving parameters, e.g., accelerations in first and second directions, during the most recent manual operation of the truck 10 to calculate a corresponding adaptive driving parameter, e.g., a maximum acceleration, to be used by the controller 103 when the truck 10 is next operated in the remote control mode.

In step 201, the controller 103 simultaneously monitors a first driving parameter, e.g. a first acceleration, corresponding to a first driving direction of the vehicle or truck 10, and a second driving parameter, e.g. a second acceleration, corresponding to a second direction different from the first driving direction during the most recent manual operation of the vehicle. In the illustrated embodiment, the first direction of travel may be defined by a direction of travel DT of the truck 10, see fig. 1, and the second direction may be defined by a lateral direction TR. Thus, the first and second directions may be substantially orthogonal to each other. The controller 103 replaces any stored data (i.e., the first stored data) regarding the monitored first and second vehicle driving parameters corresponding to previous manual operation of the vehicle by the operator with recent data (i.e., the second data) regarding the first and second vehicle driving parameters monitored during the recent manual operation of the vehicle, where the recent data was not calculated using or based on previously stored data from previous manual operation of the vehicle. The vehicle may have been operating in the remote control mode after a previous manual operation of the vehicle and prior to a most recent manual operation of the vehicle.

The operator may vary the acceleration of the truck 10 based on factors such as the curvature of the path the truck 10 is following, the steering angle of the truck 10, the current ground conditions (e.g., wet/slippery or dry/slippery floor surfaces), and/or the weight and height of any loads carried by the truck 10. For example, if the truck 10 is driven without load or with a steady load, e.g. with a load having a low height, on a long and straight path, on a dry/slippery floor surface, the value of the first acceleration may be high. However, if the truck 10 has an unstable load, e.g., the load has a high height, such that if the truck 10 accelerates quickly, the load may shift or fall from the truck 10, then the value of the first acceleration may be low. Furthermore, if the truck 10 is turning at an acute angle and driving at high speed, the value of the first acceleration may be high and the value of the second acceleration may also be high.

In step 203, the controller 103 receives a request to implement semi-autonomous driving operation, i.e., a request to operate the truck 10 in the remote control mode, after the most recent manual operation of the vehicle or truck 10. In the illustrated embodiment and as described above, the controller 103 may receive a travel request from the remote control device 70. Such a travel request may define a request to implement the first semi-autonomous driving operation.

In step 205, the controller 103 effects semi-autonomous driving operation of the truck 10 based on the first and second vehicle driving parameters monitored during the most recent manual operation of the truck 10. The controller 103 calculates a first value indicative of an acceleration of the truck 10 in a first direction and a second value indicative of an acceleration of the truck 10 in a second direction based on recent data regarding the first and second vehicle driving parameters monitored during a recent manual operation of the vehicle. If the second value falls outside the predefined range, the controller 103 modifies the first value indicative of acceleration in the first direction based on the second value indicative of acceleration in the second direction. The first value, whether modified based on the second value falling outside or within a predefined range, defines a maximum acceleration that cannot be exceeded during semi-autonomous driving operation of the truck 10.

An example control algorithm or process for the controller 103 is illustrated in fig. 4 for calculating a first value indicative of acceleration of the truck 10 in a first direction during a most recent manual operation of the truck 10. In step 301, a sequence of acceleration values in a first direction defined by the direction of travel DT of the truck 10 from the accelerometer 1103 is collected during the most recent manual operation of the vehicle and stored by the controller 103 in the memory. Rotating the travel switch 54 forward and upward will cause the truck 10 to move forward in a power unit first direction, e.g., first the power unit, with a positive acceleration proportional to the amount of rotation of the travel switch 54. Similarly, rotating the travel switch 54 toward the rear of the truck 10 and downward will cause the truck 10 to move in reverse in a first direction of the forks, e.g., first the forks, with a positive acceleration proportional to the amount of rotation of the travel switch 54. When the truck 10 is accelerating in a power unit first direction or a forks first direction (both considered to be the first direction defined by the direction of travel DT of the truck 10), the accelerometer 1103 generates a sequence of positive acceleration values, which are stored in memory by the controller 103. Rotating the travel switch 54 forward and upward while the truck 10 is moving in the fork first direction will cause the truck 10 to slow down or brake. Further, rotating the travel switch 54 in the rearward and downward directions while the truck 10 is moving in the power unit first direction will cause the truck 10 to slow down or brake. According to the first embodiment, negative acceleration values, such as occur during braking, are not collected for calculating the first value indicative of the acceleration of the truck 10 in the first direction during the most recent manual operation of the vehicle.

Although forward and upward rotation of the travel switch 54 will cause the truck 10 to move forward in the power unit first direction with positive acceleration (increasing speed), i.e., first the power unit, the accelerometer may determine that such movement includes positive acceleration. The accelerometer may also determine that braking (decreasing speed) includes deceleration or negative acceleration when the truck 10 is traveling in the power unit first direction. Further, when rotating the travel switch 54 toward the rear and downward will cause the truck 10 to move in reverse in the first direction of the forks with a positive acceleration (increasing velocity), for example, first the forks, the accelerometer may determine that such movement in which the velocity increases in the first direction of the forks includes a negative acceleration. The accelerometer may also determine that braking (decreasing speed) includes positive acceleration when the truck 10 is traveling in the first direction of the forks. However, for purposes of the discussion herein of a control algorithm for calculating the maximum acceleration that will be used during the next semi-autonomous driving maneuver, the acceleration and deceleration of the truck 10 during movement of the power unit and forks in the first direction will be defined as follows: rotating the travel switch 54 forward and upward causes the truck 10 to move forward (e.g., first the power unit) is defined as a positive acceleration (increasing speed) in the first direction of the power unit; rotating the travel switch 54 toward the rear and downward causes the truck 10 to move in a reverse direction (e.g., forks first) is defined as a positive acceleration (increasing speed) in the first direction of the forks; rotating the travel switch 54 forward and upward or actuating the brake switch 41 when the truck 10 is moving in the forks first direction causes the truck 10 to slow down or brake (with decreasing speed) is defined as a negative acceleration or deceleration; and rotating the travel switch 54 backwards and downwards or actuating the brake switch 41 when the truck 10 is moving in the power unit first direction causes the truck 10 to slow down or brake (with decreasing speed) is defined as a negative acceleration or deceleration.

As described above, according to the first embodiment, negative acceleration values, such as occur during braking in the power unit first direction or in the forks first direction, are not collected for calculating the first value indicative of the acceleration of the truck 10 in the first direction during the most recent manual operation of the vehicle. However, according to the second embodiment, both positive acceleration values (where the speed of the truck is increasing in either the power unit first direction or the fork first direction) and negative acceleration values (where the speed of the truck is decreasing in either the power unit first direction or the fork first direction) are collected and used to calculate a first value indicative of the acceleration of the truck 10 in the first direction during the most recent manual operation of the vehicle. In the second embodiment, in which the negative acceleration value is collected, the absolute value of the negative acceleration value is used in the equations and calculations described below. Thus, while some embodiments may ignore any negative acceleration data, other embodiments may consider such data by using the absolute value of the negative acceleration data in the equations and calculations described.

In step 303, acceleration values in the first direction collected during the most recent manual operation of the truck 10 are filtered using a weighted average equation to make the largest outliers less weighted and smooth. The example equation 1 listed below may be used to filter the collected acceleration values in the first direction to calculate a weighted average based on the acceleration values in the first direction collected from the most recent manual operation of the truck 10.

Equation 1:

wa_x-(i+1)a weighted average calculated in a first direction (e.g., "x"); where i is 1 … (n-1) and n is the acceleration value a collected separately_{x_j}The total number of subsets grouped therein;

wa_x-i(ii) a Wherein i is 1 … n; wa (a)_x-iAn arithmetic average of the first three "start" acceleration values in the first direction at the time of the first calculation and the most recent weighted average thereafter;

g_sa weighting factor, where s is 1 … m +1, where m is the number of members in each subset;

g₁＝wa_x-ithe weighting factor of (1); in the illustrated embodiment, g ₁3, but can be any value;

g₂，g₃，g₄additional weight factor of 1, but can be any value and is typically less than g 1;

a_{x_[(i＊m)+1]}，a_{x_[(i＊m)+2]}，a_{x_[(i＊m)+3]}wherein i is 1 … (n-1); a is_{x_[(i＊m)+1]}，a_{x_[(i＊m)+2]}，a_{x_[(i＊m)+3]}A subset is defined, collected during the most recent manual operation of the truck 10, three adjacent individual acceleration values in the first direction. The subset may include more or less than three acceleration values. The first three collected acceleration values (a)_{x_1}、a_{x_2}And a_{x_3}) Also constituting the first subset.

The first "start" acceleration value in the first direction may comprise less than three or more than three values, and the number of members in each subset "m" may likewise comprise less than three or more than three members.

For illustrative purposes, sample calculations will now be provided based on simulating unrealistic sample values of acceleration values collected in a first direction and listed in table 1 of fig. 5. All acceleration values listed in table 1 are positive values. However, as described above, negative acceleration values may also be collected and used. As described above, where negative acceleration values are collected, the absolute value of the negative acceleration values are used in the equations described and calculations set forth herein.

The remaining weighted average based on the sample values listed in table 1 of fig. 5 is calculated in a similar manner. The results are shown in table 2 of fig. 6.

Thus, for equation 1, the value a_{x_[(i＊m)+1]}，a_{x_[(i＊m)+2]}And a_{x_[(i＊m)+3]}For calculating a weighted average value wa_x-(i+1). According to the example of fig. 5, "i" may range from 1 to 9, but for equation 1, "i" ranges from 1 to 8. Thus, 27 acceleration values (i.e., a) in the table of FIG. 5_{x_j}"j" — 27 individually collected acceleration values in the example of fig. 5) may be arranged into 9 different subsets, each subset having 3 elements. In addition to the first subset (which, as described above, includes the arithmetic average of the first three "start" acceleration values in the first direction), for each of the subsequent 8 subsets, a weighted average is calculated according to equation 1. An example initial arithmetic mean and an example 8 weighted averages are shown in fig. 6. One of ordinary skill will readily recognize that a subset size of 3 values is merely an example, and that using 9 subsets is also an example quantity.

In step 305 of fig. 4, the maximum acceleration in a first direction defined by the direction of travel DT of the truck 10 is determined using the example equation 2 listed below:

equation 2: a is_x-wa-maxMax (wa) as the maximum acceleration in the first direction_x-i) Initial arithmetic and weighted average (wa) calculated_x-i) Is measured.

Based on the results of Table 2 of FIG. 6, max (wa)_x-i)＝a_x-8＝3.82。

Note that a is_x-wa-maxCan be calculated from any number of initial arithmetic and weighted averages (wa)_x-i) To select. For example, the average value (wa) calculated during a predetermined period of time (e.g., the last ten seconds) may be considered_x-i). It is also contemplated that a predetermined number of initial arithmetic and weighted averages (wa) calculated without regard to time may be considered_x-i) For example, 25 averages. It is further contemplated that all initial arithmetic and weighted averages (wa) calculated throughout the most recent manual operation of truck 10 may be considered_x-i). In the illustrated example, the initial arithmetic and weighted average (w) are considered_x-i) Nine (9) values. However, in selecting max (a)_x-wa-i) Initial arithmetic and weighted average (Wa) calculated_x-i) Maximum value of (which defines a)_x-wa-maxMaximum acceleration in the first direction), less than 9 or more than 9 initial arithmetic and weighted averages (wa) may be considered _x-i) The value of (c). Maximum acceleration (a) in a first direction_x-wa-max) A first value indicative of acceleration of the vehicle in a first direction during a most recent manual operation of the vehicle is defined. Not from consideration as the maximum acceleration a in the first direction_x-wa-maxInitial arithmetic and weighted average (wa)_x-i) Is chosen as the maximum or highest value, but instead the initial arithmetic and weighted average (wa) considered is envisaged_x-i) May be selected as the maximum acceleration a in the first direction_x-wa-max. Further imagine, the initial arithmetic and weighted average (wa) considered_x-i) May be averaged to determine a maximum acceleration a in a first direction_x-wa-max。

An example control algorithm or process for the controller 103 is illustrated in fig. 7 for calculating a second value indicative of acceleration of the truck 10 in a second direction during a most recent manual operation of the truck 10. At step 401, a sequence of acceleration values in a second direction from the accelerometer 1103 is collected, wherein the second direction is defined by the lateral direction TR, see fig. 1, and stored by the controller 103 in the memory.

In step 403, the acceleration values collected in the second direction collected during the most recent manual operation of the truck 10 are filtered using a weighted average equation to make the largest outliers less weighted and smooth. The example equation 3 listed below may be used to filter acceleration values in the second direction collected from the most recent manual operation of the truck 10.

Equation 3:

wa_y-(i+1)a weighted average in a calculated second direction (e.g., "y"); wherein i is 1 … (n-1);

wa_y-i(ii) a Wherein i is 1 … n; wa (a)_y-iAn arithmetic average of the first three "start" acceleration values in the second direction at the time of the first calculation and a most recently calculated weighted average thereafter;

g₁＝wa_y-ithe weighting factor of (1); in the illustrated embodiment, g ₁3, but can be any value;

g₂、g₃、g₄the additional weight factor is 1, but may be other values;

a_{y_[(i＊m)+1]}，a_{y_[(i＊m)+2]}，a_{y_[(i＊m)+3]}(ii) a Wherein i is 1 … (n-1); a is_{y_[(i＊m)+1]}，a_{y_[(i＊m)+2]}，a_{y_[(i＊m)+3]}Three adjacent in the second directionDefine a subset, collected during the most recent manual operation of the truck 10. The subset may include more or less than three acceleration values. The first three collected acceleration values (a)_{y_1}、a_{y_2}And a_{y_3}) Also constituting the first subset.

The first "start" acceleration value in the second direction may comprise less than three or more than three values, and the number of members in each subset "m" may likewise comprise less than three or more than three members.

For illustrative purposes, sample calculations will now be provided based on non-true sample values that simulate acceleration values collected in the second direction and are listed in Table 3 of FIG. 8.

The remaining weighted average based on the sample values listed in table 3 of fig. 8 is calculated in a similar manner. The results are shown in table 4 of fig. 9.

In step 405 of fig. 7, the maximum acceleration in the second direction defined by the lateral direction TR of the truck 10 is determined using equation 4 listed below:

equation 4: a is a_y-wa-maxMax (wa) in the second direction_y-i) Initial arithmetic sum weighted average (wa) calculated_y-i) Of (c) is calculated.

Based on the results in Table 4 of FIG. 9, max (wa)_y-i)＝wa_y-2＝0.55。

Note that a is_y-wa-maxCan be selected from the initial arithmetic mean or any number of calculated weighted means (wa)_y-(i+1)). For example, an initial arithmetic and weighted average (wa) calculated during a predetermined period of time (e.g., the last ten seconds) may be considered_y-i). Situations in which time is not considered are also envisagedA predetermined number of initial arithmetic and weighted averages (wa) calculated under the circumstances may be considered_y-i) For example, 25 averages. It is further contemplated that all initial arithmetic and weighted averages (wa) calculated throughout the most recent manual operation of truck 10 may be considered_y-i). In the illustrated example, the initial arithmetic and weighted average (wa) are considered_y-i) Three (3) values. However, in selecting max (wa)_y-i) Initial arithmetic and weighted average (wa) calculated _y-i) Maximum value of (which defines a)_y-wa-maxMaximum acceleration in the second direction), less than 3 or more than 3 initial arithmetic and weighted averages (wa) may be considered_y-i) The value of (c). Maximum acceleration (a) of the vehicle in a second direction_y-wa-max) A second value indicative of acceleration of the vehicle in a second direction during a most recent manual operation of the vehicle is defined.

An example control algorithm or process for the controller 103 is illustrated in fig. 10 for calculating a maximum acceleration to be used during a next semi-autonomous driving operation based on first and second values indicative of acceleration of the truck 10 in first and second directions during a previous or most recent manual operation of the truck 10. As described above, the first value indicative of acceleration of the truck 10 in the first direction consists of the maximum acceleration in the first direction (a)_x-wa-max) The second value defining and indicating the acceleration of the truck 10 in the second direction consists of the maximum acceleration (a) in the second direction_y-wa-max) And (4) defining. During operation of truck 10, an operator may quickly drive truck 10 along a generally straight path, but slowly drive during a turn. To account for the operator driving the truck 10 slowly during a turn, in step 501, the controller 103 applies a maximum acceleration (a) in a second direction _y-wa-max) Comparing with empirically determined ranges listed in a look-up table stored in memory to determine a maximum acceleration (a) for the first direction_x-wa-max) Is not appropriate.

As explained in detail below, the maximum acceleration (a) in the second direction when determining the maximum acceleration for the next semi-autonomous driving operation_y-wa-max) Can be used to correct or adjust the calculationsMaximum acceleration a in a first direction_x-wa-max. Maximum acceleration (a) in the second direction_y-wa-max) The operator may be instructed on an assessment of the stability of the truck 10 and its current load. If the maximum acceleration in the second direction is greater than the first empirically derived value or within an empirically derived "high acceleration" range, the operator may be instructed that the load is considered relatively stable and the maximum acceleration for the next semi-autonomous driving maneuver may be increased. However, if the maximum acceleration in the second direction is less than the second empirically derived value or falls within an empirically defined "low acceleration" range, then the operator may be instructed that the load may be unstable even if the calculated maximum acceleration in the first direction is relatively high. Therefore, in this second case, the maximum acceleration of the next semi-automatic driving operation can be reduced. If the maximum acceleration in the second direction is between the first and second empirically derived values or within an empirically defined intermediate range, no correction or adjustment is made to the maximum acceleration for the next semi-autonomous driving maneuver. The high, low and mid ranges (or empirically derived first and second values) may be empirically determined for a particular vehicle in a controlled environment in which the vehicle is operating at various maximum accelerations in a first direction and a second direction, and different values for the various high, low and mid ranges are created, and using the maximum acceleration value in the second direction, a correction factor is determined and used to adjust the maximum acceleration value in the first direction. Preferred high, low and intermediate ranges are selected which allow an optimal acceleration in the first direction while allowing the truck to carry and support a load in a stable manner.

An exemplary simulated look-up table based on non-real values is listed in FIG. 11, which contains the maximum acceleration in the second direction (a)_y-wa-max) Three separate ranges. If the maximum acceleration in the second direction falls within the high or low acceleration range depicted in the look-up table of fig. 11, the corresponding correction factor is used to determine the maximum acceleration to be used during the next semi-autonomous driving operation of the truck 10. If the maximum acceleration in the second direction falls within that depicted in the look-up table of FIG. 11In the intermediate acceleration range (or intermediate range), then the correction factor corresponding to the maximum acceleration in the second direction is not used in determining the maximum acceleration to be used during the next semi-autonomous driving operation of the truck 10.

In the example discussed above, the maximum acceleration (a) in the second direction_y-wa-max) 0.55. This value falls within the high acceleration range corresponding to a correction factor of + 10%.

In step 503, the maximum acceleration to be used during the next semi-autonomous driving operation (which may also be referred to as "semi-autonomous driving operation maximum acceleration") is calculated using example equation 5:

equation 5: acc ═ max (wa)_x-i)*(1+corr_x+corr_y)

Acc ═ maximum acceleration to be used in the first direction during the next semi-autonomous driving maneuver;

corr_xWhich may be equal to any value. In the illustrated embodiment, corr_xAcc — 5% (a negative value as in the illustrated embodiment may be included to reduce max. acc to provide a safety margin);

corr_ycorrection factor in the lookup table of fig. 11, and based on the maximum acceleration in the second direction (a)_y-wa-max)。

Sample calculation of max.acc based on the sample values discussed above will now be provided.

max.acc＝max(wa_x-i)*(1+corr_x+corr_y)＝3.82*(1-0.05+0.1)＝4.01

Thus, in this example, the controller 103 communicates with the traction motor controller 106 to limit the maximum positive acceleration (increasing speed) of the truck 10 in the first direction to 4.01m/s during the next semi-automatic or remote control operation²。

It is also contemplated that the controller 103 may calculate a first value indicative of only deceleration of the vehicle in the first direction during a most recent manual operation of the

vehicle using equations

1 and 2 listed above, wherein the absolute value of each deceleration value collected from the most recent manual operation of the vehicle is used to calculate the first

value using equations

1 and 2. The deceleration value corresponding to emergency braking, which may have a very high magnitude, is ignored in calculating the first value indicative of the deceleration of the vehicle.

In case the truck 10 does not have an accelerometer, the acceleration values in the first and second directions may be calculated in an alternative way. For example, the direction of travel DT or the acceleration in the first direction may be determined using a speed sensor, wherein the speed sensor may be provided on the traction motor controller. The controller 103 may differentiate the velocity or velocity value to calculate an acceleration value. Acceleration may also be derived from the angular position of the travel switch 54 relative to the home position, as described above, with the handle 54 controlling acceleration/braking of the truck 10. The angular position of the handle 54 is used as an input to a lookup table from which the truck acceleration is selected, which lookup table corresponds a particular handle angular position value to a particular acceleration value. The maximum speed value may also be provided by a look-up table based on the angular position of the handle.

The acceleration in the lateral direction TR or the second direction may be determined using the following equation: interception_y＝v²/r

Wherein v is truck speed; and

r is the radius of the curve through which the truck moves;

the radius r can be calculated using the following equation:

r ═ wheelbase dimension/sin α

Wherein the wheelbase dimension is a fixed value and is equal to the front to rear wheel distance of the truck 10; and

the steering angle α, which is generally known by the controller 103, is the steering wheel angle.

The table of fig. 5 represents driving parameters monitored during a single manual operation. However, embodiments also contemplate monitoring and storing driving parameter data for more than one manual operation of truck 10. For example, data for one or more driving parameters may be monitored and stored for any number of recent manual operations.

Thus, the controller 103 may define the beginning and end of each manual operation such that the data associated with each manual operation may remain separate from the data associated with the different manual operations. When an operator is on the truck 10, such as indicated by the presence sensor 58, a particular manual operation may be deemed to be initiated and the truck 10 is moved at least a minimum speed. Alternatively, a particular manual operation may be considered to be initiated when the driving signal is generated via the travel switch 54 rather than via the remote control device 70. It is further contemplated that a particular manual operation may be deemed to commence when an operator is located outside of the operator's station 30 and moves the truck via activation of a drive control switch 140 located near the top of the second end section 14B of the power unit 14 of the truck 10. A particular manual operation may be deemed to be ended when the truck 10 remains stationary for at least a predetermined period of time. Alternatively, a particular manual operation may be considered to be ended when the truck 10 is stopped and the operator leaves the truck. Alternatively, when the operator initiates a semi-autonomous driving operation via the remote control device 70, it may be considered that the specific manual operation is ended. Further, even while the truck 10 is still moving, the manual operation may be considered to be ended when the operator leaves the platform of the truck 10.

As described above, the monitored and stored data (whether from a single manual operation or from multiple manual operations) may then be used to control the implementation of the subsequently occurring semi-autonomous driving operations of the truck 10.

During or after certain driving operations of the truck 10, it may be beneficial to clear or reset stored data collected during one or more recent manual operations. For example, the data of monitored driving parameters collected and stored while the truck 10 is transporting a first pallet and items carried by or on the first pallet may not be relevant to implementing semi-autonomous driving operations once the first pallet is unloaded from the truck 10 and a new empty pallet is obtained. Accordingly, when the operator of truck 10 initiates a new picking operation, data regarding one or more driving parameters previously monitored and stored during the current manual operation of truck 10 may be discarded or reset such that only the newly monitored data regarding one or more driving parameters is used to implement a subsequently occurring semi-autonomous driving operation of truck 10. In one embodiment, only newly monitored data on one or more driving parameters collected during a current manual operation or during a manual operation immediately prior to a subsequently occurring semi-autonomous driving operation is used to implement the subsequently occurring semi-autonomous driving operation and any data of a previous manual operation occurring prior to the current manual operation or a manual operation immediately prior to the subsequently occurring semi-autonomous driving operation is ignored.

Typical inventory picking operations involve an operator filling an order from available inventory items located in storage areas provided along one or more aisles of a warehouse or distribution center. The operator drives the truck 10 between various picking positions for an item(s) I to be picked, which are typically loaded on one or more pallets P provided on the forks 16 of the load handling assembly 12, see fig. 13, where the pallets P and items I define a load L on the forks 16 or carried by the forks 16. Instead of pallets, roll cages, freezers or other special containers may be provided on the forks 16 of the load handling assembly, wherein the roll cages, freezers or other special containers and the picked items loaded thereon define the load on the forks 16 or carried by the forks 16. As described above, the operator may operate the truck 10 by manually driving the truck 10 using the steering handle 52 and the travel switches 54, or by semi-automatically controlling the vehicle in a remote control mode using the remote control device 70.

Accordingly, the controller 103 may analyze the driving operation of the truck 10 to automatically determine a sequence or pattern of operations that may indicate the start of a new picking operation. In these cases, the controller 103 may then reset or discard the collected data regarding the monitored one or more driving parameters that occurred during the current manual operation. The term "current manual operation" may refer to a manual operation that is currently occurring, the term "most recent manual operation" may refer to a manual operation that occurs immediately before the current manual operation that is still occurring, the term "previous manual operation" may refer to a manual operation that occurs before the most recent manual operation, and the term "next manual operation" may refer to a manual operation that occurs after the current manual operation. Once the "current manual operation" is finished, it may be considered as the "most recent manual operation".

Fig. 12 depicts a flowchart of an example algorithm for resetting stored data related to a first monitored vehicle driving parameter based on detecting the start of a picking operation in accordance with an embodiment of the present disclosure.

According to the method or process of fig. 12, step 1201 includes the controller 103 monitoring a first vehicle driving parameter during operator manual operation (i.e., current manual operation) of the truck 10. As described in detail above, the monitored first vehicle driving parameter may be related to acceleration of the truck 10 in a first direction.

Accordingly, in step 1203, the controller 103 may store data related to the monitored first vehicle driving parameter. In the example of fig. 5, the stored data may be various acceleration values of the truck 10 that occur during manual operation of the truck 10. Further, the stored data may include values calculated based on various acceleration values used in subsequent occurring semi-autonomous operations of the truck 10, i.e., a maximum acceleration of the truck 10 in a first direction. Thus, the controller 103 is configured to use the stored data to implement the semi-autonomous driving operation of the truck 10 that occurs after the manual operation of the truck 10 mentioned in step 1201.

However, if the stored data includes data collected during a current manual operation that occurred before a new picking operation began, then the stored data may not be relevant to semi-automatic operations that occurred after the new picking operation was initiated and completed. Accordingly, in step 1205, the controller detects operation of the truck 10 indicating the start of a picking operation occurring during current manual operation of the truck 10. Upon detecting the start of the picking operation, the controller 103 may then reset the stored data relating to the monitored first vehicle driving parameter in step 1207. Resetting the stored data may include clearing or discarding stored data collected during the current manual operation of truck 10 from the beginning of the current manual operation until a new or most recent picking operation is detected and initiated.

Once the stored data is reset, the controller 103 may resume monitoring the first vehicle driving parameter after resetting the stored data. This newly acquired data relating to monitoring the first driving parameter may then be used to effect a subsequently occurring semi-autonomous driving operation of the vehicle.

In at least one embodiment, the detected operation of the truck 10 indicating the start of a picking operation includes detecting a transition from the truck 10 being manually driven with the load handling assembly 12 raised to the truck 10 being stopped with the load handling assembly 12 lowered, see fig. 13. In other words, the controller 103 detects that the truck 10 being moved by manual operation has now stopped and also detects that the load handling assembly 12 in the raised position has been lowered. As described above, the controller 103 may determine whether the truck 10 is moving or stopped and the distance the truck has traveled via a signal from the accelerometer 1103 or a motor angular velocity signal from the traction controller 106. As also described above, the controller 103 may determine the height of the load handling assembly 12, i.e. whether the load handling assembly is in a raised position or in a home or lowest position relative to the ground, from the signal generated by one or more of the height sensors or switches, either alone or in combination with the load sensor LS. The raised position of the load handling assembly 12 may be any position above the lowermost position. This sequence of operations particularly indicates the start of a new picking operation when the elevated load handling assembly 12 is subjected to a substantially non-zero load and the lowered load handling assembly 12 is subjected to a substantially zero load. As described above, the controller 103 may determine the weight of the load on the forks 16 from the signal generated by the load sensor LS. In fig. 13, the forks 16 of the load handling assembly 12 have been lowered so that the pallet P is no longer supported by the forks 16, but rather by the floor F or other ground-defining support surface. Thus, for example, this sequence occurs when the truck 10 transitions from moving with a loaded pallet P to stopping and then lowers its forks 16 completely so that the forks 16 no longer support the loaded pallet P. It is contemplated that the sequence of operations may indicate the start of a new picking operation even when the elevated load handling assemblies 12 are carrying empty pallets or are not carrying pallets.

In a further embodiment, the detected operation of the truck 10 indicating the start of a picking operation includes detecting a transition from the truck 10 being manually driven with the load handling assembly 12 raised to the truck 10 being stopped with the load handling assembly 12 lowered, as shown in fig. 13, and detecting that the truck 10 moves a distance at least equal to the length of the load L on the forks 16 after the forks 16 are lowered, see fig. 14. In the example of fig. 14, the length of the forks 16 is only slightly greater than the length of the pallet P. However, it is envisaged that the truck may have forks of extended length so that the forks can carry more than one pallet of conventional size at the same time. In such embodiments, the forks may carry only one pallet at the ends of the forks, or two or more pallets along the entire length of the forks. For example, a spot laser or ultrasonic device may be provided in the second end section 14B for sensing the distance from the second end section 14B to a pallet, such as one positioned at the end of a pallet fork. Thus, the truck 10 may be moved a distance equal to the length of the load L by moving only the length of a single pallet when only a single pallet is provided on the forks, or by moving a distance equal to the length of two or more pallets when two or more pallets are provided on the forks. Thus, once the forks 16 are lowered and they are not carrying any load, movement of the truck 10 (without any load on the forks 16) would presumably indicate that the truck 10 is unloading a pallet that it had previously carried.

The above sequence of operations is even more indicative of a new picking operation when the detected operation of the truck 10 also includes a determination that the operator is driving the truck 10 with the load handling assembly 12 lowered while it is carrying a substantially zero load. It is relevant (as described above) that the truck 10 moves a distance at least equal to the length of the load carried by the forks, but driving the truck 10 without a load a distance greater than the length of the forks 16 is even more indicative of the start of a new pick operation.

In yet another embodiment, the detected operation of the truck 10 indicating the start of a picking operation includes detecting a transition from the truck 10 being manually driven with the load handling assembly 12 raised to the truck 10 being stopped with the load handling assembly 12 lowered, as shown in fig. 13; detecting that the truck 10 has moved a distance at least equal to the length of the load L on the forks 16 after the forks 16 are lowered, as shown in fig. 14; determining that the operator has driven the truck 10 with the load handling assembly 12 lowered while it is carrying a substantially zero load; and a transition from the truck 10 moving with the load handling assembly 12 lowered to the truck 10 being stopped with the load handling assembly 12 newly raised. In this case, the truck 10 has traveled some distance with the load handling assembly 12 substantially empty and lowered and has now stopped, wherein after stopping, the operator then raises the load handling assembly 12. This sequence of operations indicates the start of a new picking operation, particularly when the now elevated load handling assembly 12 is subjected to a load less than a predetermined amount, but greater than substantially zero load, such as the weight of an empty pallet, roll cage, freezer or other special container. The predetermined amount may include the weight of a conventional empty pallet, roll cage, freezer, or other special container.

In other words, the truck 10 has a substantially non-zero load (i.e., it is carrying a pallet P with an item I), and then the truck 10 stops, lowers the pallet P and the item I on the pallet P, wherein the pallet P and item I define the load L on the forks 16, and continues to move with the load handling assembly 12 lowered. In particular, the lowered load handling assembly 12 supports substantially no load and therefore experiences substantially zero load when the truck 10 is moving. The truck 10 is then stopped and the load handling assembly 12 is raised so that the now raised load handling assembly 12 is loaded but less than a predetermined amount. One such example would be when the load handling assembly 12 is carrying only empty pallets P such that the operator is about to begin a new picking operation. In these cases, the controller 103 may detect from the load sensor LS that the previously lowered load handling assembly 12 is empty and is experiencing a substantially zero load, but is now experiencing a weight of the pallet that is at least greater than the substantially zero load. However, the weight of the pallet P itself is less than the weight of the pallet plus the item or items I on the pallet P; thus, the controller 103 determines from the signal generated by the load sensor LS that the load handling assembly 12 is experiencing a load greater than substantially zero load but less than the load of a loaded or semi-loaded pallet. Thus, when detecting that the now raised load handling assembly 12 is experiencing a load less than a predetermined amount, the controller 103 may detect that the load-bearing assembly 12 is experiencing a load equal to the weight of a conventional empty pallet.

As described above with respect to step 1207, once the controller 103 detects the start of the picking operation, the controller 103 may reset the stored data relating to the monitored first vehicle driving parameter. Further, the stored data may include data related to a second vehicle driving parameter monitored during manual operation of the truck 10 by an operator, wherein the controller 103 is configured to effect semi-autonomous driving operation of the truck 10 using the stored data of the monitored first and second vehicle driving parameters after the manual operation of the truck 10. Thus, in step 1207, the controller 103 may then reset the stored data relating to the monitored first vehicle driving parameter and the monitored second vehicle driving parameter. Thus, the controller 103 may calculate the maximum acceleration a in the first direction using equations 1-5 listed above, as well as stored data collected since the beginning of the most recent picking operation relating to the monitored first and second vehicle driving parameters, while ignoring data collected prior to the most recent picking operation_x-wa-maxAnd maximum acceleration (a) in a second direction_y-wa-max) And determining from these calculations a maximum acceleration max.acc to be used in the first direction during the next semi-autonomous driving operation.

U.S. provisional patent application No.62/892,213 entitled "Adaptive adaptation for Materials Handling Vehicle" filed on 27.8.2019 is incorporated by reference in its entirety and U.S. sequence No.16/943,567 filed on 30.7.2020 is also incorporated by reference in its entirety.

Having thus described the present application in detail and by reference to the embodiments and drawings thereof, it will be apparent that modifications and variations are possible without departing from the scope defined in the appended claims.

Claims

1. A method for operating a materials handling vehicle comprising: monitoring, by a controller, a first vehicle driving parameter during manual operation of a vehicle by an operator; storing, by a controller, data relating to the monitored first vehicle driving parameter, the controller being configured to effect semi-autonomous driving operation of the vehicle using the stored data after manual operation of the vehicle; detecting, by a controller, an operation of a vehicle indicating a start of a picking operation occurring during a manual operation of the vehicle; and resetting, by the controller, stored data related to the monitored first vehicle driving parameter based on detecting the start of the picking operation.

2. The method of claim 1, comprising: monitoring of the first vehicle driving parameter is resumed by the controller after resetting the stored data.

3. A method as claimed in any one of claims 1 or 2, wherein the detected operation of the vehicle comprises a transition from the vehicle being manually driven with a raised load handling assembly to the vehicle being stopped with a lowered load handling assembly.

4. The method of claim 3 wherein the elevated load handling assembly is subjected to a substantially non-zero load.

5. A method as claimed in any one of claims 3 or 4, wherein the lowered load handling assembly is subjected to substantially zero load.

6. The method of any of claims 3-5, wherein the load handling assembly includes one or more forks, and the detected operation of the vehicle further comprises movement of the vehicle.

7. The method of claim 6, wherein the moving is for a distance at least equal to a length of a load carried by the forks.

8. The method of claim 7, wherein the movement of the vehicle for a distance at least equal to the length of the load carried by the forks occurs after the vehicle transitions to being stopped with the lowered load handling assembly.

9. The method of any of claims 1-8, wherein the detected operation of the vehicle further comprises driving the vehicle with the load handling assembly lowered.

10. The method of claim 9, wherein the lowered load handling assembly is subjected to substantially zero load.

11. A method as claimed in any of claims 3 to 10, wherein the detected operation of the vehicle further comprises a transition from the vehicle moving with the load handling assembly lowered to the vehicle being stopped with the load handling assembly subsequently raised.

12. The method of claim 11, wherein the subsequently elevated load handling assembly is subjected to a load less than a predetermined amount but greater than substantially zero load.

13. The method of claim 1, wherein the detected operation of the vehicle comprises: a first transition from the vehicle being manually driven with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered; movement of the vehicle with the lowered load handling assembly by a distance at least equal to the length of the load carried by the load handling assembly, said movement occurring after the first transition; and a second transition from the vehicle moving with the load handling assembly lowered to the vehicle stopped with the load handling assembly newly raised.

14. The method of claim 13 wherein during the second transition, the lowered load handling assembly is subjected to a substantially zero load and the newly raised load handling assembly is subjected to a load less than a predetermined amount but greater than the substantially zero load.

15. The method of any one of claims 1-14, further comprising: monitoring, by the controller, a second vehicle driving parameter during manual operation of the vehicle by the operator; and storing, by a controller, data relating to the monitored second vehicle driving parameter, the controller being configured to effect semi-autonomous driving operation of the vehicle using the stored data of the monitored first and second vehicle driving parameters following manual operation of the vehicle.

16. A system for operating a materials handling vehicle comprising: a memory storing executable instructions; and a processor in communication with the memory, wherein execution of the executable instructions by the processor causes the processor to: monitoring a first vehicle driving parameter during manual operation of the vehicle by an operator; storing data relating to the monitored first vehicle driving parameter, the controller being configured to effect semi-autonomous driving operation of the vehicle using the stored data following manual operation of the vehicle; detecting operation of the vehicle indicating a start of a picking operation occurring during manual operation of the vehicle; and resetting the stored data relating to the monitored first vehicle driving parameter based on detecting the start of the picking operation.

17. The system of claim 16, wherein execution of the executable instructions by the processor causes the processor to: after resetting the stored data, monitoring of the first vehicle driving parameter is resumed.

18. A system as claimed in claim 16 or 17 in which the detected operation of the vehicle comprises a transition from the vehicle being driven manually with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered.

19. The system of claim 18 wherein the elevated load handling assembly is subjected to a substantially non-zero load.

20. The system of claim 18 or 19, wherein the lowered load handling assembly is subjected to substantially zero load.

21. The system as claimed in any one of claims 18 to 20, wherein the load handling assembly comprises one or more forks and the detected operation of the vehicle further comprises movement of the vehicle.

22. The system of claim 21, wherein the movement is for a distance at least equal to a length of a load carried by the forks.

23. The system of claim 22, wherein movement of the vehicle a distance at least equal to a length of a load carried by the forks occurs after the vehicle transitions to being stopped with the lowered load handling assembly.

24. The system as claimed in any one of claims 16-23, wherein the detected operation of the vehicle further comprises driving the vehicle with the load handling assembly lowered.

25. The system of claim 24, wherein the lowered load handling assembly is subjected to substantially zero load.

26. A system as claimed in any one of claims 18 to 25 in which the detected operation of the vehicle further comprises a transition from the vehicle moving with the load handling assembly lowered to the vehicle being stopped with the load handling assembly subsequently raised.

27. The system of claim 26 wherein the subsequently elevated load handling assembly is subjected to a load less than a predetermined amount but greater than substantially zero load.

28. The system of claim 16, wherein the detected operation of the vehicle comprises: a first transition from the vehicle being manually driven with the load handling assembly raised to the vehicle being stopped with the load handling assembly lowered; movement of the vehicle with the lowered load handling assembly by a distance at least equal to the length of the load carried by the load handling assembly, said movement occurring after the first transition; and a second transition from the vehicle moving with the load handling assembly lowered to the vehicle stopped with the load handling assembly newly raised.

29. The system of claim 28 wherein during the second transition, the lowered load handling assembly is subjected to a substantially zero load and the newly raised load handling assembly is subjected to a load less than a predetermined amount but greater than the substantially zero load.

30. The system of any of claims 16-29, wherein execution of the executable instructions by the processor causes the processor to: monitoring a second vehicle driving parameter during manual operation of the vehicle by the operator; storing data relating to the monitored second vehicle driving parameter, the controller being configured to effect semi-autonomous driving operation of the vehicle using the stored data of the monitored first and second vehicle driving parameters following manual operation of the vehicle.