System and method for hands on steering wheel detection

Abstract

A method for hands-on-the-wheel detection includes receiving a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle and generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal. The method also includes synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal. The method also includes generating an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. The method also includes determining whether the vehicle operator's hands are on the steering wheel based on the operator torque estimate signal.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to U.S. Provisional Patent Application Serial No. 63 / 287,485, filed on December 8, 2021, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to steering systems, and in particular to hands-on-wheel detection of steering systems. Background Art

[0004] Vehicles such as automobiles, trucks, sport utility vehicles, crossovers, minivans, boats, aircraft, all-terrain vehicles, recreational vehicles, or other suitable forms of transportation typically include a steering system, such as an electric power steering (EPS) system, a steer-by-wire (SbW) steering system, a hydraulic steering system, or other suitable steering system. The steering system of such a vehicle typically controls various aspects of the vehicle's steering, including providing steering assistance to the vehicle's operator, controlling the vehicle's steerable wheels, and the like. Summary of the Invention

[0005] The present disclosure generally relates to steering systems.

[0006] One aspect of the disclosed embodiment includes a method for hands-on-the-wheel detection. The method includes receiving a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle, and generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal. The method also includes synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal, and generating an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. The method also includes determining whether the operator of the vehicle has their hands on the steering wheel based on the operator torque estimate signal.

[0007] Another aspect of the disclosed embodiment includes a system for hands-on-the-wheel detection. The system includes a processor and a memory. The memory includes instructions that, when executed by the processor, cause the processor to: receive a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle; generate a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; generate an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal; and determine whether the vehicle operator's hands are on the steering wheel based on the operator torque estimate signal.

[0008] Another aspect of the disclosed embodiment includes an apparatus for hands-on-steering-wheel detection. The apparatus includes a processor and a memory. The memory includes instructions that, when executed by the processor, cause the processor to: receive a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle; generate a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; calculate a damping value by multiplying a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scaled value; calculate an inertia value by multiplying a steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and a steering wheel inertia scaled value; calculate a friction value by multiplying a friction direction signal and a friction magnitude scaled value; generate a delayed valve torque signal by delaying a received valve torque signal; generate an operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed received valve torque signal; and determine whether the vehicle operator's hands are on the steering wheel based on the operator torque estimate signal.

[0009] These and other aspects of the present disclosure are disclosed in the following detailed description of the embodiments, the appended claims and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present disclosure will be best understood from the following detailed description when read in conjunction with the accompanying drawings. It is emphasized that, according to common practice, the various features of the drawings are not drawn to scale. Instead, the dimensions of the various features are arbitrarily expanded or reduced for clarity.

[0011] Figure 1 A vehicle according to the principles of the present disclosure is generally shown.

[0012] Figure 2 A controller according to the principles of the present disclosure is generally shown.

[0013] Figure 3 A recirculating ball steering gear according to the principles of the present disclosure is generally shown.

[0014] Figure 4 A hydraulic steering system spherical steering gear is generally shown according to the principles of the present disclosure.

[0015] Figure 5A-5B A schematic diagram generally illustrates a hydraulic steering system control system according to the principles of the present disclosure.

[0016] Figure 6 A schematic diagram of a hands on the steering wheel detection system according to the principles of the present disclosure is generally shown.

[0017] Figure 7A-7BA schematic diagram of an alternative hands on the wheel detection system in accordance with the principles of the present disclosure is generally shown.

[0018] Figure 8 A schematic diagram of an alternative hands on the wheel detection system in accordance with the principles of the present disclosure is generally shown.

[0019] Figure 9A-9B A schematic diagram of an alternative hands on the wheel detection system in accordance with the principles of the present disclosure is generally shown.

[0020] Figure 10 A schematic diagram of an alternative hands on the wheel detection system in accordance with the principles of the present disclosure is generally shown.

[0021] Figure 11 A schematic diagram of an alternative hands on the wheel detection system in accordance with the principles of the present disclosure is generally shown.

[0022] Figure 12 is a flow chart generally illustrating a hands on the steering wheel detection method according to the principles of the present disclosure. DETAILED DESCRIPTION

[0023] The following discussion is directed to various embodiments of the present disclosure. Although one or more of these embodiments may be preferred, the disclosed embodiments should not be interpreted or otherwise used to limit the scope of the present disclosure, including the claims. In addition, those skilled in the art will understand that the following description has broad application, and the discussion of any embodiment is intended only to be an exemplary discussion of that embodiment, and is not intended to imply that the scope of the present disclosure, including the claims, is limited by that embodiment.

[0024] As described, vehicles such as automobiles, trucks, sport utility vehicles, crossovers, minivans, boats, aircraft, all-terrain vehicles, recreational vehicles, or other suitable forms of transportation typically include a steering system, such as an electric power steering (EPS) system, a steer-by-wire (SbW) steering system, a hydraulic steering system, or other suitable steering system. The steering system of such a vehicle typically controls various aspects of the vehicle's steering, including providing steering assistance to the vehicle's operator, controlling the vehicle's steerable wheels, and the like.

[0025] Typically, hydraulic steering systems use a power steering pump to provide pressurized hydraulic fluid to a recirculating ball steering gear or a rack and pinion style steering gear. The level of torque assistance provided in such steering systems (e.g., to the vehicle operator) is determined by the amount of torque the operator applies to a steering valve that is integrated into the steering gear.

[0026] exist Figure 3A cross-section of a recirculating ball steering gear is generally shown in the figure. The gear includes an input shaft that is operably connected to the steering wheel of the vehicle. When torque is applied to the input shaft, a valve assembly is actuated to provide assist pressure in chamber A or chamber B, depending on the direction of the torque, thereby assisting in steering the vehicle. A worm is attached to the bottom of the valve assembly, which provides thrust on the rack. As the valve assembly rotates in the steering gear, the rack translates along the axis of the worm in the rack hole. The rack has teeth that mesh with teeth on the rocker shaft. As the rack moves axially in the rack hole, the rocker shaft rotates along its axis. A link arm is attached to the bottom of the rocker shaft, connecting the rocker shaft to a linkage mechanism in the vehicle. As the rocker shaft rotates, the rocker arm swings through an arc. This moves the steering linkage mechanism in the vehicle, causing the front wheels to be angled to steer the vehicle.

[0027] Some hydraulic steering systems incorporate magnetic actuators into the valve assembly. Such steering systems allow for the implementation of advanced algorithms on the hydraulic system, such as variable force, leads and pulls correction, active damping, active return, etc. This can also provide the opportunity to receive torque commands from external algorithms on the vehicle, which can be included in the output torque.

[0028] exist Figure 4 A cross-section of a recirculating ball steering gear of such a hydraulic steering system (e.g., including a magnetic actuator) is generally shown in FIG. As generally shown, the assistance and connection from the steering wheel and wheels are functionally the same as a basic gear. The gear includes a magnetic actuator incorporated into a valve assembly to provide additional force to assist or hinder the operator during certain steering conditions. Under these conditions, a controller provides current to a coil, which determines the amount of torque provided by the magnetic actuator.

[0029] exist Figure 5A-5B A high-level block diagram of the controls for a hydraulic steering system is generally shown in FIG. Measurements of the pressure differential across the piston in the steering system, along with various vehicle signals (e.g., vehicle speed, steering wheel speed and angle, and an estimate of operator torque), are used to generate a desired torque command. An external torque command signal and an external torque enable signal may also be received from the vehicle (e.g., by a controller). The external torque enable signal is evaluated along with signals such as the pressure differential, steering wheel angle, vehicle speed, and a hands-on-the-wheel detection signal to determine whether conditions are acceptable for enabling the external torque command.

[0030] The external command limit block then determines the amount of external signal to apply. The final torque block combines the internal and external torque commands to provide a final torque command. This torque command is provided to a current command module, which converts the desired torque command into a required current command, which is applied to the magnetic actuator coil in the steering gear. This current command, along with the measured pressure differential, is used to generate an estimate of the operator torque, which can be used in the next cycle.

[0031] The estimated operator torque may be used by the hands on the wheel detection block to generate a signal indicating whether the operator's hands are on the steering wheel. Figure 6 An example of a hands on the wheel detection frame is generally shown in FIG. The estimated operator torque signal is filtered. The absolute value of the filtered estimated operator torque is used together with the vehicle speed to select a gain value from a lookup table. The gain value typically has a high positive value when the torque level is high and a high negative value when the torque is close to zero. The gain value is multiplied by the periodic rate of the steering wheel detection frame and integrated over time. Limits of 1 and -1 are applied to the integrated signal. The limited signal can be filtered before outputting the final hands on the steering wheel detection signal.

[0032] The estimated operator torque determined in this application is the torque applied across the hydraulic valve assembly. While this provides a reasonable estimate of the operator torque during low steering wheel speeds and steady-state conditions, it does not account for the inertia, damping, and friction effects of the steering wheel and joystick (column). This can lead to errors during rapid steering maneuvers.

[0033] Accordingly, systems and methods, such as those described herein, that are configured to provide improved hands-on-the-wheel detection may be desirable. In some embodiments, the systems and methods described herein may be configured to use a steering wheel angle signal in addition to an estimated operator torque signal to improve performance during rapid steering wheel movements.

[0034] Figure 7A-7B A high-level block diagram of the controls for the steering system is generally shown, including a hands on wheel detection block. The systems and methods described herein can be configured to use two input signals: a steering wheel angle signal and an updated steering wheel angle signal. The systems and methods described herein can be configured to receive the steering wheel angle signal from a serial communication device or system of the vehicle. This signal may not be updated at the same periodic rate as the hands on wheel detection block. The systems and methods described herein can be configured to set the updated steering wheel angle signal to true when the steering wheel angle signal is updated on the serial communication bus.

[0035] The systems and methods described herein can be configured to set the steering wheel angle signal to false when the steering wheel angle signal is retained from a previous cycle. The systems and methods described herein can be configured to use the updated steering wheel angle signal to modify the value of the steering wheel angle signal at the hands on the steering wheel detection cycle rate (e.g., even if the steering wheel angle signal from the serial communication has not changed).

[0036] Figure 8 The hands on the wheel detection box is generally shown. The systems and methods described herein can be configured to use data from (e.g., Figures 7A-7B The estimated torque of the torque estimation box and the use of elements that reflect the dynamic effects of the steering wheel and joystick (column) as a function of the steering wheel speed and steering wheel acceleration.

[0037] In some embodiments, the systems and methods described herein can be configured to use the steering wheel angle (HWA) to calculate the steering wheel speed (HWS) and the steering wheel acceleration (Acc). For example, the systems and methods described herein can be configured to calculate the HWS at time step 1 from the HWA at time step 0 and time step 2, which can be defined as follows:

[0038] HWS1 = (HWA0 – HWA2) / (2*dT), where dT = the time difference between time steps

[0039] The systems and methods described herein can be configured to use a memory block associated with the controller to store the value of HWS at additional time steps (e.g., such as HWS2, HWS3, HWS4, or other suitable time steps). The systems and methods described herein can be configured to use the HWS at time steps 1 and 3 to calculate the Acc at time step 2, which can be defined as follows:

[0040] Acc2 = (HWS1 – HWS3) / (2*dT), where dT = the time difference between time steps

[0041] The systems and methods described herein may be configured to use a storage box to store Acc values at additional time steps (eg, such as Acc3, Acc4, or other suitable time steps).

[0042] Thus, as generally shown, the earliest time step at which HWS can be calculated is delayed by one time step from the current time step, while the earliest time step at which Acc can be calculated is delayed by two time steps from the current time step. To minimize errors in estimated operator torque during rapid steering maneuvers, the systems and methods described herein can be configured to synchronize steering wheel-related signals so that the calculated HWS and Acc values reference the same time step. For example, delayed HWS = HWS2, and delayed Acc = Acc2.

[0043] In some embodiments, the systems and methods described herein can be configured to estimate the values of HWS and Acc when the hands on the wheel detection frame is calculated but the HWA has not yet been refreshed, apply an additional time step delay for a total of three time step delays, and linearly increment the values of HWS and Acc between HWS2 and HWS3 and between Acc2 and Acc3. For example, if the steering wheel angle is updated every fifth time, the systems and methods described herein calculate the hands on the wheel detection frame. The systems and methods described herein can be configured to calculate a HWS increment that is one-fifth of the difference between HWS2 and HWS3, which can be defined as follows:

[0044] HWS Inc =(HWS2–HWS3) / 5

[0045] The systems and methods described herein may be configured to include the HWS each time a hands on the wheel detection frame is executed. Inc Added to the previous value of the delayed HWS until the HWA signal is updated.

[0046] Similarly, the systems and methods described herein can be configured to calculate an Acc delta that is one-fifth the difference between Acc2 and Acc3, which can be defined as follows:

[0047] Acc Inc =(Acc2–Acc3) / 5

[0048] The systems and methods described herein can be configured to set Acc to Inc Added to the previous value of Acc delayed until the HWA signal is updated.

[0049] As described, Figure 9A-9B The delayed steering wheel angle signal block that implements the delayed HWA related signal is generally shown. When the update signal value is true, the systems and methods described herein can be configured to calculate the delayed HWS and delayed Acc signals and the HWS Inc Signal and Acc Inc Signals, such as Figure 10 As shown in the figure.

[0050] When the update signal value is false, the systems and methods described herein can be configured to use the HWS Inc Signal and Acc Inc The value of the signal is incremented by the delayed HWS and delayed Acc signals (e.g., Figure 11 (roughly shown in ).

[0051] Reference again Figure 8 The systems and methods described herein can be configured to calculate an operator torque estimate signal and pass the signal to a hands-on-the-wheel detection integration routine. The systems and methods described herein can be configured to calculate the operator torque estimate signal by determining the sum of four signals representing a damping component, an inertia component, a friction component, and a valve torque component. The damping component is calculated by multiplying the delayed steering wheel velocity signal by a damping coefficient scaling value.

[0052] The inertia component is calculated by multiplying the delayed steering wheel acceleration signal by the steering wheel inertia scale value. The friction component is calculated by multiplying the friction direction signal by the friction magnitude scale value. The initial friction direction signal is determined by the sign of the delayed steering wheel speed signal. If the delayed steering wheel speed signal is positive, the initial direction signal is 1. If the delayed steering wheel speed signal is negative, the initial direction signal is -1. If the delayed steering wheel speed signal is zero, the initial direction signal is the same as the value from the previous cycle.

[0053] The systems and methods described herein can be configured to apply a low pass filter to the initial friction direction signal to obtain a final friction direction signal that transitions from 1 to -1 or from -1 to 1 at a slower rate. Figure 7A-7B The torque estimation block in FIG. 1 is a Trq Est signal having a delay applied thereto. This delay is calibrable to allow the Trq Est signal to be synchronized with the delayed steering wheel angle signal (e.g., this can minimize, reduce, or eliminate errors during fast steering maneuvers).

[0054] It should be noted that the damping coefficient, steering wheel inertia, and friction magnitude scaling values can be implemented in various forms. They can be constant values in the code, constant calibrated values, or values determined from a calibrable lookup table based on other signals (e.g., vehicle speed).

[0055] In some embodiments, the systems and methods described herein can be configured to provide a means for calculating a hands-on-the-wheel detection signal. The systems and methods described herein can be configured to use a steering wheel angle signal received from a vehicle. The systems and methods described herein can be configured to calculate steering wheel speed and steering wheel acceleration signals based on the steering wheel angle signal. The systems and methods described herein can be configured to delay the steering wheel speed and steering wheel acceleration signals in order to synchronize the steering wheel speed and steering wheel acceleration signals.

[0056] The systems and methods described herein can be configured to calculate steering wheel velocity and steering wheel acceleration signals for each execution of a hands on the steering wheel detection frame (e.g., even if the steering wheel angle signal is not updated). The systems and methods described herein can be configured to modify the signals linearly for time steps at which the steering wheel angle signal is not updated. The systems and methods described herein can be configured to estimate operator torque using damping, inertia, and friction. The systems and methods described herein can be configured to use a delayed estimate of valve torque in order to synchronize the torque estimate with the delayed steering wheel generated signal. The systems and methods described herein can be configured to use a filter to reduce the rate of change of the direction of applied friction.

[0057] In some embodiments, the systems and methods described herein can be configured to receive a steering wheel angle signal from a sensor associated with a vehicle's steering wheel, the steering wheel being associated with the vehicle's EPS steering system, SbW steering system, hydraulic steering system (e.g., including a magnetic actuator incorporated into a valve assembly of the hydraulic steering system), or other suitable steering system.

[0058] The systems and methods described herein can be configured to generate a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by a steering wheel angle signal. The systems and methods described herein can be configured to synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal. The systems and methods described herein can be configured to generate an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. For example, the systems and methods described herein can be configured to calculate a damping value by determining the product of a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scale value.

[0059] The systems and methods described herein can be configured to calculate an inertia value by determining the product of a steering wheel acceleration value indicated by a delayed steering wheel acceleration signal and a steering wheel inertia scale value. The systems and methods described herein can be configured to calculate a friction value by determining the product of a friction direction signal and a friction magnitude scale value. The systems and methods described herein can be configured to generate a delayed valve torque signal by delaying a received valve torque signal. The systems and methods described herein can be configured to generate an operator torque estimate signal based on a damping value, an inertia value, a friction value, and a delayed valve torque signal. The systems and methods described herein can be configured to determine whether the operator of the vehicle has their hands on the steering wheel based on the operator torque estimate signal.

[0060] Figure 1 A vehicle 10 is generally shown in accordance with the principles of the present disclosure. Vehicle 10 may include any suitable vehicle, such as a car, truck, sport utility vehicle, minivan, crossover, any other passenger vehicle, any suitable commercial vehicle, or any other suitable vehicle. Although vehicle 10 is illustrated as a passenger vehicle having wheels and used on a road, the principles of the present disclosure may be applied to other vehicles, such as airplanes, ships, trains, drones, or other suitable vehicles.

[0061] Vehicle 10 includes a vehicle body 12 and a hood 14. A passenger compartment 18 is at least partially defined by vehicle body 12. Another portion of vehicle body 12 defines an engine compartment 20. Hood 14 can be removably attached to a portion of vehicle body 12 such that hood 14 provides access to engine compartment 20 when hood 14 is in a first, or open, position and covers engine compartment 20 when hood 14 is in a second, or closed, position. In some embodiments, engine compartment 20 can be positioned at the rear of vehicle 10 compared to what is generally shown.

[0062] The passenger compartment 18 may be disposed rearward of the engine compartment 20, but in embodiments where the engine compartment 20 is disposed in a rear portion of the vehicle 10, the passenger compartment 18 may be disposed forward of the engine compartment 20. The vehicle 10 may include any suitable propulsion system, including an internal combustion engine, one or more electric motors (e.g., an electric vehicle), one or more fuel cells, a hybrid propulsion system including a combination of an internal combustion engine, one or more electric motors (e.g., a hybrid vehicle), and / or any other suitable propulsion system.

[0063] In some embodiments, vehicle 10 may include a gasoline engine or a gasoline-fueled engine, such as a spark-ignition engine. In some embodiments, vehicle 10 may include a diesel-fueled engine, such as a compression-ignition engine. An engine compartment 20 houses and / or surrounds at least some components of the propulsion system of vehicle 10. Additionally or alternatively, propulsion control devices (e.g., an accelerator actuator (e.g., an accelerator pedal), a brake actuator (e.g., a brake pedal), a steering wheel, and other such components) are disposed in a passenger compartment 18 of vehicle 10. The propulsion control devices may be actuated or controlled by an operator of vehicle 10 and may be directly connected to corresponding components of the propulsion system, such as a throttle, brakes, axles, a vehicle transmission, etc., respectively. In some embodiments, the propulsion control devices may transmit signals to a vehicle computer (e.g., a drive-by-wire vehicle computer), which in turn may control corresponding propulsion components of the propulsion system. Thus, in some embodiments, vehicle 10 may be an autonomous vehicle.

[0064] In some embodiments, vehicle 10 includes a transmission that communicates with the crankshaft via a flywheel, a clutch, or a fluid coupling. In some embodiments, the transmission comprises a manual transmission. In some embodiments, the transmission comprises an automatic transmission. Vehicle 10 may include one or more pistons that, in the case of an internal combustion engine or a hybrid vehicle, operate in conjunction with the crankshaft to generate force that is transmitted through the transmission to one or more axles, thereby rotating wheels 22. When vehicle 10 includes one or more electric motors, the vehicle battery and / or fuel cell provides energy to the electric motors to rotate wheels 22.

[0065] Vehicle 10 may include an automated vehicle propulsion system, such as cruise control, adaptive cruise control, automatic braking control, other automated vehicle propulsion systems, or combinations thereof. Vehicle 10 may be an automated or semi-automated vehicle, or another suitable type of vehicle. Vehicle 10 may include additional or fewer features than generally shown and / or disclosed herein.

[0066] In some embodiments, the vehicle 10 may include an Ethernet component 24, a controller area network (CAN) bus 26, a media oriented system transport component (MOST) 28, a FlexRay component 30 (e.g., a brake-by-wire system, etc.), and a local interconnect network component (LIN) 32. The vehicle 10 may use the CAN bus 26, MOST 28, FlexRay component 30, LIN 32, other suitable networks or communication systems, or a combination thereof, to communicate various information from sensors within or outside the vehicle to various processors or controllers within or outside the vehicle. The vehicle 10 may include additional or fewer features than generally shown and / or disclosed herein.

[0067] In some embodiments, the vehicle 10 may include a steering system, such as an EPS system, a steer-by-wire steering system (e.g., which may include or communicate with one or more controllers that control components of the steering system without using a mechanical connection between a steering wheel and the wheels 22 of the vehicle 10), a hydraulic steering system (e.g., which may include a magnetic actuator incorporated into a valve assembly of the hydraulic steering system), or other suitable steering systems.

[0068] The steering system may include an open-loop feedback control system or mechanism, a closed-loop feedback control system or mechanism, or a combination thereof. The steering system may be configured to receive various inputs, including but not limited to steering wheel position, input torque, one or more wheel positions, other suitable inputs or information, or a combination thereof.

[0069] Additionally or alternatively, the input may include steering wheel torque, steering wheel angle, motor speed, vehicle speed, estimated motor torque command, other suitable inputs, or combinations thereof. The steering system may be configured to provide steering functionality and / or control to the vehicle 10. For example, the steering system may generate assist torque based on various inputs. The steering system may be configured to selectively control a motor of the steering system using the assist torque to provide steering assistance to the operator of the vehicle 10.

[0070] In some embodiments, the vehicle 10 may include a controller, such as Figure 2 Controller 100 is generally shown in FIG. Controller 100 may include any suitable controller, such as an electronic control unit or other suitable controller. For example, controller 100 may be configured to control various functions of the steering system and / or various functions of vehicle 10. Controller 100 may include a processor 102 and a memory 104. Processor 102 may include any suitable processor, such as those described herein. Additionally or alternatively, controller 100 may include any suitable number of processors in addition to or in addition to processor 102. Memory 104 may include a single disk or multiple disks (e.g., a hard drive) and include a storage management module that manages one or more partitions within memory 104. In some embodiments, memory 104 may include flash memory, semiconductor (solid-state) memory, etc. Memory 104 may include random access memory (RAM), read-only memory (ROM), or a combination thereof. Memory 104 may include instructions that, when executed by processor 102, cause processor 102 to control at least various aspects of vehicle 10.

[0071] The controller 100 may receive one or more signals from various measurement devices or sensors 106 that are indicative of sensed or measured characteristics of the vehicle 10. The sensors 106 may include any suitable sensors, measurement devices, and / or other suitable mechanisms. For example, the sensors 106 may include one or more torque sensors or devices, one or more steering wheel position sensors or devices, one or more motor position sensors or devices, one or more position sensors or devices, other suitable sensors or devices, or combinations thereof. The one or more signals may indicate steering wheel torque, steering wheel angle, motor speed, vehicle speed, other suitable information, or combinations thereof.

[0072] In some embodiments, the controller 100 can be configured to provide hands-on steering wheel detection. For example, the controller 100 can receive a steering wheel angle signal from one or more sensors 106 (e.g., such as a steering wheel position sensor 106 or other suitable sensor 106 or other suitable sensor) and / or receive a steering wheel angle signal associated with one or more sensors 106, the one or more sensors 106 being associated with a steering wheel and / or a joystick of the vehicle 10. The controller 100 can generate a steering wheel speed signal and a steering wheel acceleration signal based on the steering wheel angle indicated by the steering wheel angle signal.

[0073] The controller 100 may synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal. The controller 100 may generate an operator torque estimation signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. For example, the controller 100 may calculate a damping value by determining the product of a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scale value.

[0074] The controller 100 can calculate the inertia value by determining the product of the steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and the steering wheel inertia scale value. The controller 100 can also calculate the friction value by determining the product of the friction direction signal and the friction magnitude scale value. The controller 100 can generate a delayed valve torque signal by delaying the received valve torque signal.

[0075] The controller 100 may generate an operator torque estimation signal based on the damping value, the inertia value, the friction value, and the delayed valve torque signal. The controller 100 may determine whether the vehicle operator's hands are on the steering wheel based on the operator torque estimation signal.

[0076] In some embodiments, the controller 100 can perform the methods described herein. However, the methods described herein as being performed by the controller 100 are not meant to be limiting, and any type of software executed on a controller or processor can perform the methods described herein without departing from the scope of this disclosure. For example, a controller (e.g., a processor executing software within a computing device) can perform the methods described herein.

[0077] Figure 12 is a flow chart generally illustrating a hands on the steering wheel detection method 300 according to the principles of the present disclosure. At 302, the method 300 receives a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle. For example, the controller 100 may receive the steering wheel angle signal from the sensor 106 associated with the steering wheel of the vehicle 10.

[0078] At 304 , method 300 generates a steering wheel speed signal and a steering wheel acceleration signal based on the steering wheel angle indicated by the steering wheel angle signal. For example, controller 100 may generate a steering wheel speed signal and a steering wheel acceleration signal based on the steering wheel angle indicated by the steering wheel angle signal.

[0079] At 306 , the method 300 synchronizes the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal. For example, the controller 100 may synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal.

[0080] At 308 , method 300 generates an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. For example, controller 100 may generate the operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal.

[0081] At 310 , method 300 determines whether the vehicle operator's hands are on the steering wheel based on the operator torque estimate signal. For example, controller 100 may determine whether the vehicle operator's hands are on the steering wheel based on the operator torque estimate signal.

[0082] In some embodiments, a method for hands-on-the-wheel detection includes receiving a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle, and generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal. The method also includes synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal. The method also includes generating an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. The method also includes determining whether the operator of the vehicle has their hands on the steering wheel based on the operator torque estimate signal.

[0083] In some embodiments, the steering wheel is associated with an electric power steering system of the vehicle. In some embodiments, the steering wheel is associated with a hydraulic steering system of the vehicle. In some embodiments, the hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system. In some embodiments, generating an operator torque estimate signal based on at least a delayed steering wheel speed signal and a delayed steering wheel acceleration signal includes: calculating a damping value by determining a product of a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scale value; calculating an inertia value by determining a product of a steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and a steering wheel inertia scale value; calculating a friction value by determining a product of a friction direction signal and a friction magnitude scale value; generating a delayed valve torque signal by delaying a received valve torque signal; and generating the operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed valve torque signal.

[0084] In some embodiments, a method for hands-on-the-wheel detection includes receiving a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle, and generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal. The method also includes synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal, and generating an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal. The method also includes determining whether an operator of the vehicle has their hands on the steering wheel based on the operator torque estimate signal.

[0085] In some embodiments, the steering wheel is associated with an electric power steering system of the vehicle. In some embodiments, the steering wheel is associated with a hydraulic steering system of the vehicle. In some embodiments, the hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system. In some embodiments, the method further includes calculating a damping value by determining a steering wheel speed value indicated by a delayed steering wheel speed signal and a damping coefficient scaled value; and calculating an inertia value by determining a steering wheel acceleration value indicated by a delayed steering wheel acceleration signal and a steering wheel inertia scaled value. In some embodiments, the method further includes calculating a friction value by determining a friction direction signal and a friction magnitude scaled value; and generating a delayed valve torque signal by delaying a received valve torque signal. In some embodiments, generating an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal includes generating the operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed received valve torque signal. In some embodiments, the sensor associated with the steering wheel of the vehicle includes a steering wheel position sensor.

[0086] In some embodiments, a system for hands-on-the-wheel detection includes a processor and a memory. The memory includes instructions that, when executed by the processor, cause the processor to: receive a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle; generate a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; generate an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal; and determine whether an operator of the vehicle has their hands on the steering wheel based on the operator torque estimate signal.

[0087] In some embodiments, the steering wheel is associated with an electric power steering system of the vehicle. In some embodiments, the steering wheel is associated with a hydraulic steering system of the vehicle. In some embodiments, the hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system. In some embodiments, the instructions further cause the processor to calculate a damping value by determining a steering wheel speed value indicated by a delayed steering wheel speed signal multiplied by a damping coefficient scaled value; and to calculate an inertia value by determining a steering wheel acceleration value indicated by a delayed steering wheel acceleration signal multiplied by a steering wheel inertia scaled value. In some embodiments, the instructions further cause the processor to calculate a friction value by determining a friction direction signal multiplied by a friction magnitude scaled value; and to generate a delayed valve torque signal by delaying a received valve torque signal. In some embodiments, the instructions further cause the processor to generate an operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal by generating the operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed received valve torque signal. In some embodiments, the sensor associated with the steering wheel of the vehicle includes a steering wheel position sensor.

[0088] In some embodiments, an apparatus for hands-on-steering wheel detection includes a processor and a memory. The memory includes instructions that, when executed by the processor, cause the processor to: receive a steering wheel angle signal from a sensor associated with a steering wheel of a vehicle; generate a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronize the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; calculate a damping value by multiplying a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scaled value; calculate an inertia value by multiplying a steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and a steering wheel inertia scaled value; calculate a friction value by multiplying a friction direction signal and a friction magnitude scaled value; generate a delayed valve torque signal by delaying a received valve torque signal; generate an operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed received valve torque signal; and determine whether the hands of the vehicle operator are on the steering wheel based on the operator torque estimate signal.

[0089] In some embodiments, the steering wheel is associated with an electric power steering system of the vehicle. In some embodiments, the steering wheel is associated with a hydraulic steering system of the vehicle. In some embodiments, the hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system.

[0090] The above discussion is intended to illustrate the principles of the present invention and various embodiments. Once the above disclosure is fully understood, many changes and modifications will become apparent to those skilled in the art. The following claims are intended to be interpreted as including all such changes and modifications.

[0091] The word "example" is used herein to mean used as an example, instance or illustration. Any aspect or design described herein as an "example" is not necessarily to be construed as being preferred or advantageous over other aspects or designs. On the contrary, the use of the word "example" is intended to present concepts in a concrete form. As used in this application, the term "or" is intended to mean an inclusive "or" rather than an exclusive "or". That is, unless otherwise stated or clear from the context, "X includes A or B" is intended to mean any common inclusive arrangement. That is, if X includes A; X includes B; or X includes both A and B, then "X includes A or B" is satisfied in any of the foregoing cases. In addition, the article "a / an" used in this application and the appended claims should generally be interpreted to mean "one or more" unless otherwise stated or clear from the context to refer to a singular form. In addition, unless so described, the use of the term "embodiment" or "one embodiment" throughout the text is not intended to mean the same embodiment or embodiment.

[0092] Implementations of the systems, algorithms, methods, and instructions described herein may be implemented in hardware, software, or any combination thereof. Hardware may include, for example, a computer, intellectual property (IP) core, an application-specific integrated circuit (ASIC), a programmable logic array, an optical processor, a programmable logic controller, microcode, a microcontroller, a server, a microprocessor, a digital signal processor, or any other suitable circuitry. In the claims, the term "processor" should be understood to include any of the foregoing hardware, alone or in combination. The terms "signal" and "data" are used interchangeably.

[0093] As used herein, the term module can include a packaged functional hardware unit designed for use with other components, a set of instructions executable by a controller (e.g., a processor executing software or firmware), processing circuitry configured to perform a specific function, and self-contained hardware or software components that interface with a larger system. For example, a module can include an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA), an electrical circuit, a digital logic circuit, an analog circuit, a combination of discrete circuits, gate circuits, and other types of hardware, or a combination thereof. In other embodiments, a module can include a memory that stores instructions that a controller can execute to implement the module's functionality.

[0094] Furthermore, in one aspect, for example, the systems described herein can be implemented using a general-purpose computer or general-purpose processor with a computer program that, when executed, performs any corresponding method, algorithm, and / or instruction described herein. Additionally or alternatively, for example, a special-purpose computer / processor can be utilized that can include other hardware for performing any method, algorithm, or instruction described herein.

[0095] Furthermore, all or part of the implementation of the present disclosure may take the form of a computer program product accessible from, for example, a computer-usable or computer-readable medium. A computer-usable or computer-readable medium may be, for example, any device that can tangibly contain, store, communicate, or transport a program for use by or in connection with any processor. The medium may be, for example, an electronic, magnetic, optical, electromagnetic, or semiconductor device. Other suitable media may also be used.

[0096] The above embodiments, implementations, and aspects have been described to facilitate understanding of the present invention and are not intended to limit the present invention. Rather, the present invention is intended to cover various modifications and equivalent arrangements within the scope of the appended claims, which scope should be given the broadest interpretation to encompass all such modifications and equivalent structures permitted by law.

Claims

1. A method for detecting hands on a steering wheel, the method comprising: receiving a steering wheel angle signal from a sensor associated with a steering wheel of the vehicle; generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; generating an operator torque estimate signal based on at least the delayed steering wheel velocity signal and the delayed steering wheel acceleration signal; as well as determining whether an operator of the vehicle has hands on the steering wheel based on the operator torque estimate signal; The method further comprises: calculating a damping value by determining a product of a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scale value; calculating an inertia value by determining a product of a steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and a steering wheel inertia scale value; calculating a friction value by determining the product of the friction direction signal and the friction magnitude scale value; and generating a delayed valve torque signal by delaying the received valve torque signal; Wherein, generating the operator torque estimation signal based at least on the delayed steering wheel speed signal and the delayed steering wheel acceleration signal includes generating the operator torque estimation signal based on the damping value, the inertia value, the friction value and the delayed received valve torque signal.

2. The method according to claim 1, wherein The steering wheel is associated with an electric power steering system of the vehicle.

3. The method according to claim 1, wherein The steering wheel is associated with a hydraulic steering system of the vehicle.

4. The method according to claim 3, wherein: The hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system.

5. The method according to claim 1, wherein Sensors associated with a steering wheel of the vehicle include a steering wheel position sensor.

6. A system for detecting hands on a steering wheel, the system comprising: processor; as well as a memory comprising instructions that, when executed by the processor, cause the processor to: receiving a steering wheel angle signal from a sensor associated with a steering wheel of the vehicle; generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; generating an operator torque estimate signal based on at least the delayed steering wheel velocity signal and the delayed steering wheel acceleration signal; as well as determining whether an operator of the vehicle has hands on the steering wheel based on the operator torque estimate signal; The instructions further cause the processor to: calculating a damping value by determining a product of a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scale value; calculating an inertia value by determining a product of a steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and a steering wheel inertia scale value; calculating a friction value by determining the product of the friction direction signal and the friction magnitude scale value; and generating a delayed valve torque signal by delaying the received valve torque signal; The instructions further cause the processor to generate the operator torque estimate signal based on at least the delayed steering wheel speed signal and the delayed steering wheel acceleration signal in the following manner: generating the operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed received valve torque signal.

7. The system according to claim 6, wherein: The steering wheel is associated with an electric power steering system of the vehicle.

8. The system according to claim 6, wherein: The steering wheel is associated with a hydraulic steering system of the vehicle.

9. The system according to claim 8, wherein: The hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system.

10. The system according to claim 6, wherein: Sensors associated with a steering wheel of the vehicle include a steering wheel position sensor.

11. A device for detecting whether a person is holding a steering wheel, the device comprising: processor; a memory comprising instructions that, when executed by the processor, cause the processor to: receiving a steering wheel angle signal from a sensor associated with a steering wheel of the vehicle; generating a steering wheel speed signal and a steering wheel acceleration signal based on a steering wheel angle indicated by the steering wheel angle signal; synchronizing the steering wheel speed signal and the steering wheel acceleration signal by generating a delayed steering wheel speed signal and a delayed steering wheel acceleration signal; calculating a damping value by determining a product of a steering wheel speed value indicated by the delayed steering wheel speed signal and a damping coefficient scale value; calculating an inertia value by determining a product of a steering wheel acceleration value indicated by the delayed steering wheel acceleration signal and a steering wheel inertia scale value; The friction value is calculated by determining the product of the friction direction signal and the friction magnitude scale value; generating a delayed valve torque signal by delaying the received valve torque signal; generating an operator torque estimate signal based on the damping value, the inertia value, the friction value, and the delayed received valve torque signal; as well as Based on the operator torque estimate signal, it is determined whether an operator of the vehicle has hands on the steering wheel.

12. The device according to claim 11, wherein The steering wheel is associated with an electric power steering system of the vehicle.

13. The device according to claim 11, wherein The steering wheel is associated with a hydraulic steering system of the vehicle.

14. The device according to claim 13, wherein The hydraulic steering system includes a magnetic actuator incorporated into a valve assembly of the hydraulic steering system.

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