Steering assembly

A steering assembly for a machine is provided. The steering assembly includes a frame. The steering assembly also includes a steering column mounted on the frame. The steering column includes a steering input device and a controller communicably coupled to the steering input device. The steering assembly further includes a steering wheel operably coupled to the steering column. The steering wheel is disposed adjacent to the steering input device.

TECHNICAL FIELD

The present disclosure relates to a steering assembly. More particularly, the present disclosure relates to the steering assembly for a machine.

BACKGROUND

Vehicles, such as construction machines, include a steering assembly provided in association with wheels of the vehicle in order to provide a desired steering of the wheels and maneuverability of the vehicle on ground. In many autonomous applications, the vehicle may include a dual steering system. The dual steering system may include a hydro-mechanical manual steering system and a path guided electronic steering system. In a semi-autonomous or an autonomous operating mode of the vehicle, the electronic steering system may be active and the manual steering system may be present, but non-functional. In a manual operating mode of the vehicle, the manual steering system may be active and the electronic steering system may be present, but non-functional. As such, the dual steering system provides redundant steering system, in turn, increasing complexity and costs. Hence, there is a need for an improved steering assembly for such applications.

U.S. Pat. No. 6,053,274 describes a cable-type steering device. Operation of a steering wheel is transmitted to a steering gear box through two cables. In the cable-type steering device, a steering torque inputted to the steering wheel is detected by a steering torque detector provided between the steering wheel and the cables. The operation of a motor for a power steering operation for driving the steering gear box is controlled based on the detected steering torque. The steering torque detected by the steering torque detector includes the friction of the cables and hence, a steering torque offsetting the friction of the cables can be generated in the motor for the power steering operation, thereby providing an appropriate steering feeling. A hydraulic power steering device may be used instead of or in addition to a motor for a power steering operation.

SUMMARY OF THE DISCLOSURE

In an aspect of the present disclosure, a steering assembly for a machine is provided. The steering assembly includes a frame. The steering assembly also includes a steering column mounted on the frame. The steering column includes a steering input device and a controller communicably coupled to the steering input device. The steering assembly further includes a steering wheel operably coupled to the steering column. The steering wheel is disposed adjacent to the steering input device.

In another aspect of the present disclosure, a machine is provided. The machine includes a chassis. The machine also includes a steering assembly mounted on the chassis. The steering assembly includes a frame. The steering assembly also includes a steering column mounted on the frame. The steering column includes a steering input device and a controller communicably coupled to the steering input device. The steering assembly further includes a steering wheel operably coupled to the steering column. The steering wheel is disposed adjacent to the steering input device.

DETAILED DESCRIPTION

Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts. Referring toFIG. 1A, an exemplary machine100is illustrated. In the illustrated embodiment, the machine100is a mining truck. The machine100is adapted to transport material such as ore, soil, rocks, and so on from one location to another. In other embodiments, the machine100may be any other machine such as an off-highway truck, an underground mining truck, a haul truck, a dozer, a wheel loader, a wheel tractor scraper, and so on. The machine100may be any machine related to an industry including, but not limited to, construction, transportation, mining, material handling, aviation, marine, and waste management.

The machine100includes a chassis102. The chassis102supports various components of the machine100. The machine100includes an enclosure104provided on the chassis102. The enclosure104houses a power source (not shown) of the machine100. The power source provides power to the machine100for operational and mobility requirements. The power source may be any power source, such as an internal combustion engine, an electric motor, a battery, and so on. Additionally, the enclosure104may also include various components and systems (not shown) of the machine100, such as an engine system, a transmission system, an electric drive system, a drive control system, an engine control system, a lubrication system, a cooling system, an air supply system, and so on.

The machine100includes a load bed106provided on the chassis102. The load bed106is adapted to load and unload material therefrom for transporting the material from one location to another. The machine100also includes one or more hydraulic cylinders108coupled between the chassis102and the load bed106. The hydraulic cylinders108tilt the load bed106during unloading of the material. The machine100also includes a set of ground wheels110rotatably mounted to the chassis102. The ground wheels110support and provide mobility to the machine100on ground. It should be noted that the machine100may be an autonomous machine, a semi-autonomous machine, a remotely operated machine, a remotely supervised machine, a manually operated machine, and so on, based on application requirements.

The machine100also includes an operator cabin112mounted on the chassis102. The operator cabin112houses one or more controls (not shown), such as a pedal, a lever, a control console, buttons, knobs, audio visual system, alarm system, and so on. The controls are adapted to operate and control the machine100on the ground. Additionally, the operator cabin112also includes an operator seat202(shown inFIG. 2) and a steering assembly204(shown inFIG. 2) mounted on the chassis102. The operator seat202provides a seating surface for an operator (not shown) present in the operator cabin112. The steering assembly204is adapted to maneuver the machine100on the ground.

FIG. 1Billustrates another machine114, according to an embodiment of the present disclosure. The machine114is embodied as an articulated truck. The machine114includes a chassis116similar to the chassis102(seeFIG. 1A), an enclosure118similar to the enclosure104(seeFIG. 1A) for housing an engine (not shown), and an operator cabin120mounted on the chassis116. The operator cabin120includes an operator seat (not shown) and a steering assembly (not shown) mounted on the chassis116. The steering assembly is adapted to maneuver the machine114on grounds. The steering assembly of the machine114is similar to the steering assembly204(seeFIG. 2) associated with the machine100(seeFIG. 1A).

For exemplary purposes, the steering assembly204associated with the machine100will now be explained in detail. However, it should be noted that the description provided below is equally applicable to the steering assembly associated with the machine114, without limiting the scope of the present disclosure.

Referring toFIGS. 2 and 3, an assembled view and an exploded view of the steering assembly204is illustrated, respectively. The steering assembly204will be hereinafter interchangeably referred to as the “assembly204”. The assembly204will now be explained with combined reference toFIGS. 2 and 3. The assembly204includes a frame206mounted on the chassis102. In one embodiment, the frame206may have a single unit structure. In other embodiments, the frame206may have a multi-unit structure. The frame206may be made of any material, such as a metal, an alloy, a polymer, a combination thereof and so on. Also, the frame206may be manufactured using any process, such as casting, fabrication, molding, additive manufacturing, and so on.

The assembly204also includes a steering column208. The steering column208will be hereinafter interchangeably referred to as the “column208”. The column208is mounted on the frame206. In the illustrated embodiment, the column208is mounted on the frame206using an adjustment mechanism210. The adjustment mechanism210will be hereinafter interchangeably referred to as the “adjuster210”. In other embodiments, the column208may be directly mounted on the frame206, such that the adjuster210may be omitted.

In an example, the column208redundantly measures a steering input provided via a steering wheel212. The column208has rotational stops (not shown) for limiting a rotation of the column208in a clockwise direction or an anti-clockwise direction. Further, the column208includes an electric motor or an electric device that is electronically controlled to provide a tactical or haptic steering feedback to the operator through the steering wheel212.

The tactical or haptic steering feedback provided by the column208may include, for example, higher steering resistance with increased rotation of the steering wheel212, higher steering resistance at increased ground speed, higher steering resistance as the steering wheel212approaches the rotational stops, low notch resistance when the machine100is moving in a forward direction, vibration when the machine100approaches a predetermined boundary, and the like.

The assembly204also includes the steering wheel212. The steering wheel212will be hereinafter interchangeably referred to as the “wheel212”. The wheel212is operably coupled to the column208. Further, the assembly204also includes a first steering Electronic Control Unit (ECU)205and a second steering ECU207. The first and second steering ECUs205,207may be disposed between the mechanism408and the controller406. The first and second steering ECUs205,207may receive values corresponding to input signals received via the wheel212, actual steer angle feedback, steering value spool position, steering pressure, and the like. In some examples, the first and second steering ECUs205,207may also receive values corresponding to engine speed, ground speed of the machine100, transmission gear position, secondary steering status, operator presence, pitch, yaw, or roll of the machine100, machine payload, traction control, and the like.

Referring toFIG. 4, a schematic representation of a portion of the assembly204is illustrated. As shown in the accompanying figure, the column208includes a Steering Input Device (SID)402. The steering input device402will be hereinafter interchangeably referred to as the “SID402” The SID402is disposed within a housing404of the column208. The SID402is directly coupled to the wheel212. The SID402directly supports the wheel212via a shaft on bearing arrangement (not shown) that is provided within the SID402. Accordingly, the wheel212is disposed adjacent to the SID402. In a manual mode of the machine100, the SID402is configured to receive the steering input from the operator via the wheel212. Further, the SID402is configured to generate a signal indicative of a magnitude of the steering input. The SID402may be any known electronic steering input unit and may include other elements (not shown), such as one or more rotation sensors, torque sensors, rotation stops, an electric motor, a control unit, and so on, based on application requirements.

Further, if the operator wants to take control of the machine100, the SID402allows switching of the machine100from an autonomous mode to the manual mode based on grasping of the wheel212by the operator. More particularly, the SID402allows switching of the machine100from the autonomous mode to the manual mode based on sensing of a misalignment between the steering input received from the operator via the wheel212and an autonomous steering path signal. Further, once the machine100switches to the manual mode, the machine100can be switched back to the autonomous mode when the machine100is fully stopped and an autonomous start-up sequence is completed. Moreover, when the machine100is in the manual mode during machine start-up, the SID402compares the position of the wheel212with the actual steer angle. If the position of the wheel212is not in alignment with the actual steer angle, the SID402sends out a signal to rotate the wheel212so that the position of the wheel212corresponds to the actual steer angle to allow machine operation.

The column208also includes a controller406. The controller406may be any control unit configured to perform various functions of a steering system. In one embodiment, the controller406may be a dedicated control unit configured to perform functions related to the steering system. In another embodiment, the controller406may be a Machine Control Unit (MCU) associated with the machine100, an Engine Control Unit associated with the engine, and so on configured to perform functions related to the steering system. The controller406is communicably coupled to the SID402and a steering mechanism408. The steering mechanism408will be hereinafter interchangeably referred to as the “mechanism408”.

Accordingly, in the manual mode of the machine100, the controller406is configured to receive the signal indicative of the magnitude of the steering input from the SID402. Based on the received signal, the controller406is configured to actuate and/or control the mechanism408in order to steer the ground wheels110. Additionally, the controller406is configured to measure an actual steer angle of the ground wheels110and compare the actual steer angle of the ground wheels110with the steering input. Further, the controller406is configured to actuate and/or control the mechanism408until the actual steer angle of the ground wheels110is equal to the steering input. In one embodiment, the mechanism408may be a hydraulic type steering mechanism. In other embodiments, the mechanism408may be an electronic/electrical type steering mechanism.

In a semi-autonomous mode of the machine100, the controller406may be configured to augment the steering input received from the wheel212and the SID402. Also, in the semi-autonomous mode and/or an autonomous mode of the machine100, the controller406is configured to receive a signal indicative of a desired steering of the machine100from an autonomous control system (not shown), such as a path guidance system, associated with the machine100and communicably coupled to the controller406. Based on the received signal, the controller406is configured to actuate and/or control the mechanism408in order to steer the ground wheels110. In such a situation, the controller406is also configured to actuate and/or control the SID402in order to align the wheel212relative to the actual steer angle of the ground wheels110. Further, in some examples, the actual steer angle feedback in the form of a semi-autonomous or autonomous signal is sent to the first and second steering ECUs205,207to ensure alignment of the wheel212with the actual machine steer angle, without any limitations.

Referring back toFIGS. 2 and 3, the assembly204also includes the adjuster210. The adjuster210is disposed between the frame206and the column208. The adjuster210includes amounting bracket214. The mounting bracket214defines a central axis C-C′. The mounting bracket214is fixedly coupled to the frame206using one or more fasteners216, such as screws, nuts, bolts, pins, and so on. Additionally, the mounting bracket214includes several first teeth302. The first teeth302will be explained in more detail later. The mounting bracket214may be made of any material, such as a metal, an alloy, a polymer, a combination thereof, and so on. Also, the mounting bracket214may be manufactured using any process, such as casting, fabrication, molding, additive manufacturing, and so on.

The adjuster210also includes a pivoting bracket218. The pivoting bracket218is movably coupled to the mounting bracket214using a first pivot joint304. The first pivot joint304defines a first pivot axis F-F′. Accordingly, the pivoting bracket218is adapted to selectively pivot about the first pivot joint304and the first pivot axis F-F′ relative to the mounting bracket214. The pivoting bracket218may be movably coupled to the mounting bracket214at the first pivot joint304using any fastener306, such as a pin, and so on. The pivoting bracket218may be made of any material, such as a metal, an alloy, a polymer, a combination thereof, and so on. Also, the pivoting bracket218may be manufactured using any process, such as casting, fabrication, molding, additive manufacturing, and so on.

The adjuster210also includes a telescoping bracket220. The telescoping bracket220is movably coupled to the pivoting bracket218. More specifically, the telescoping bracket220includes a base portion308, a guide portion310, and a mounting portion312. The base portion308is fixedly coupled to the pivoting bracket218using one or more fasteners (not shown), such as screws, bolts, nuts, pins, and so on. The guide portion310is slidably coupled to the base portion308. The guide portion310has a substantially elongated configuration. As such, the guide portion310is adapted to selectively move relative to the base portion308along the central axis C-C′. Accordingly, the telescoping bracket220is adapted to selectively move relative to the pivoting bracket218along the central axis C-C′. In this example, the mounting portion312is fixedly coupled to the guide portion310using mechanical fasteners, such as bolts, screws, pins, and the like. In other examples, the mounting portion312may be fixedly coupled to the guide portion310by other joining methods, such as by welding, and so on. In some embodiments, the mounting portion312may be integrally manufactured with the guide portion310.

The mounting portion312includes a rack portion316and a base plate318. The rack portion316is coupled to the guide portion310. The base plate318is coupled to the rack portion316. The rack portion316includes several second teeth320. The second teeth320will be explained in more detail later. The base plate318is adapted to removably receive the column208on the telescoping bracket220. The telescoping bracket220may be made of any material, such as a metal, an alloy, a polymer, a combination thereof, and so on. Also, the telescoping bracket220may be manufactured using any process, such as casting, fabrication, molding, additive manufacturing, and so on.

In the illustrated embodiment, the adjuster210further includes one or more mounting plates222. The mounting plates222are removably coupled to the base plate318of the telescoping bracket220using one or more fasteners324, such as screws, bolts, nuts, pins, and so on. The mounting plates222are adapted to removably mount the column208on the telescoping bracket220. The column208may be removably coupled to the mounting plates222using any fasteners (not shown), such as screws, bolts, nuts, pins, and so on. In some embodiments, the column208may be directly mounted on the base plate318of the telescoping bracket220. In such a situation, the mounting plates222may be omitted.

The adjuster210further includes a locking member224. The locking member224is movably coupled to the pivoting bracket218using a second pivot joint328. The second pivot joint328defines a second pivot axis S-S′. Accordingly, the locking member224is adapted to selectively pivot about the second pivot joint328and the second pivot axis S-S′ relative to the pivoting bracket218in a disengaged position and an engaged position. The locking member224may be movably coupled to the pivoting bracket218at the second pivot joint328using any fastener330, such as a pin, and so on. The locking member224includes a number of locking teeth332. As such, the locking member224is adapted to selective engage with each of the first teeth302and the second teeth320. The locking member224may be made of any material, such as a metal, an alloy, a polymer, a combination thereof, and so on. Also, the locking member224may be manufactured using any process, such as casting, fabrication, molding, additive manufacturing, and so on.

More specifically, in the disengaged position of the locking member224, the locking teeth332of the locking member224disengage with each of the first teeth302of the mounting bracket214and each of the second teeth320of the telescoping bracket220. As such, the pivoting bracket218may pivot about the first pivot joint304and the first pivot axis F-F′ relative to the mounting bracket214in order to move each of the telescoping bracket220, the mounting plates222, the locking member224, the column208, and the wheel212in a direction “D1” (shown inFIG. 3).

Also, the telescoping bracket220may slide relative to the pivoting bracket218along the central axis C-C′ in order to move each of the telescoping bracket220, the mounting plates222, the locking member224, the column208, and the wheel212in a direction “D2”. Further, in the engaged position of the locking member224, the locking teeth332of the locking member224engage with each of the first teeth302of the mounting bracket214and each of the second teeth320of the telescoping bracket220in order to secure the wheel212in a desired operating position. As such, in the engaged position of the locking member224, movement of the wheel212in each of the directions “D1”, “D2” is limited.

Referring toFIG. 5, a top view of a portion of the assembly204is illustrated. It should be noted that several components of the assembly204are omitted in the accompanying figure for purpose of explanation and clarity. The assembly204also includes several control stalks502. In the illustrated embodiment, the control stalks502are coupled to the mounting plates222. In other embodiments, the control stalks502may be directly coupled to the column208. In such a situation, the mounting plates222may be omitted. Also, the control stalks502are disposed adjacent to the column208. The control stalks502are adapted to control one or more elements (not shown) associated with the machine100, such as windshield wipers, windshield fluid, headlights, indicator lights, drive control modes, engine operating modes, machine operating modes, transmission shift, retarding controls, and so on, based on application requirements.

INDUSTRIAL APPLICABILITY

The present disclosure is related to the assembly204and positioning of the column208relative to the wheel212. The assembly204provides a simple, efficient, fail-safe, and cost-effective method to provide a manual, a semi-automated, and/or an automated steering control using the assembly204. The assembly204described herein can be incorporated in an Ackerman steering linkage system associated with mining trucks or an articulation steering linkage system associated with articulated trucks, without any limitations.

In the manual, the semi-autonomous, and/or the autonomous mode of the machine100, the SID402coupled to the wheel212may include rotation stops and may provide a haptic steering feedback to the operator, in turn, improving usability and operability. The haptic steering feedback may provide variable steering resistance of the wheel212based on rotating speed of the wheel212by the operator, ground speed of the machine100, modulation zones, predefined operating/hazardous conditions, difference between the steering input and the actual steer angle of the ground wheels110, and so on. It should be noted that the haptic feedback from the SID402is such that the operator can override the haptic feedback. Thus, the SID402is designed to follow the steering input even if the haptic feedback is being overridden by the operator.

Further, the SID402also allows switching of the machine100from the autonomous mode to the manual mode. Moreover, when the machine100is in the manual mode during machine start-up, the SID402sends out the signal to align the wheel212with the actual steer angle to allow machine operation. In the semi-autonomous and/or the autonomous mode of the machine100, the SID402may align the wheel212relative to the actual steer angle of the ground wheels110, in turn, providing switching from the autonomous steering control to the manual steering control while the machine100may be in motion.

The SID402provides a rotational range of the wheel212independent of the steering mechanism408. More specifically, the SID402provides a reduced rotational range, such as less than 360 degrees, of the wheel212for a complete angular range of the steering mechanism408. As such, the reduced rotational range of the wheel212reduces tracking issues in rotation software, limits redundant use of rotation sensors, reduces need for wire routing for 360 degrees rotation, reduces labor effort during operation of the wheel212, limits need for accessories, such as steering wheel spinners, and so on. Further, reduction in the rotational range may allow easy integration of rotation switches, toggles, or control pad into the steering wheel212for operator control of display of the machine100, radio, control features, and the like. Thus, such features may be accessed by the operator without having to remove their hands from the steering wheel212, thereby improving ergonomics and operator comfort.

The assembly204provides a direct connection between the wheel212and the SID402to control a quality as well as degree of freedom of the steering wheel212. This direct connection in turn, reduces mechanical dead band, hysteresis, friction/drag, shaft cogging, universal joint cogging, backlash of spline joints, misalignment of the wheel212relative to the ground wheels110, other mechanical disturbances, improving operator steering input and haptic steering feedback, and so on.

The control stalks502are mounted on the column208, in turn, providing movement of the control stalks502with the wheel212during adjustment, providing constant relative position between the wheel212and the control stalks502, providing clear line of sight to control stalk icons and a dashboard information display (not shown) through the wheel212, and so on. The assembly204includes limited mechanical and/or hydraulic components disposed within the operator cabin112, in turn, improving noise attenuation, improving protection from environmental factors, and improving service life of the assembly204. Also, the assembly204has a limited footprint within the operator cabin112, in turn, improving legroom for the operator. Further, the assembly204has no components mounted externally on the operator cabin112, in turn, reducing complexity and costs.

The adjuster210provides a single lever based tilt and telescopic adjustment of the wheel212using the locking member224, in turn, improving ergonomics for the operator. The wheel212may have neutral buoyancy when making ergonomic adjustments, in turn, improving usability and operability. Further, the locking member224may automatically engage as the operator may release the locking member224and may provide a positive engagement of the locking member224, in turn, limiting disengagement during rough terrain operation. Additionally, the adjuster210may include bump stops at extreme adjustment ranges, in turn, providing an intuitive operation of the adjuster210for the operator. The assembly204may be retrofitted in any operator cabin/machine with little or no modification to existing operator cabin/machine, in turn, improving flexibility, improving compatibility, increasing volumes, increasing standardization and consistency across product lines, reducing tooling modifications, reducing costs, and so on.

While aspects of the present disclosure have been particularly shown and described with reference to the embodiments above, it will be understood by those skilled in the art that various additional embodiments may be contemplated by the modification of the disclosed machines, systems and methods without departing from the spirit and scope of the disclosure. Such embodiments should be understood to fall within the scope of the present disclosure as determined based upon the claims and any equivalents thereof.