DISPLAY SYSTEM FOR LAWNMOWER AND LAWNMOWER INCLUDING DISPLAY SYSTEM

A display system for a drive-by-wire lawnmower having first and second motors can include first and second operator inputs configured to transmit a first and second motor signals, respectively, first and second displays mounted on the first and second operator inputs, respectively, and a controller. The controller can be configured for electrical communication with the first motor, the second motor, and in electrical communication with the first operator input, the second operator input, the first display, and the second display. The controller can be configured to determine a respective drive speed and a respective drive direction for each of the first motor and the second motor based on both of the first drive signal and the second drive signal, and cause the first display and the second display to present a predetermined pattern based on the first motor signal and the second motor signal

BACKGROUND

The disclosed subject matter relates to a self-propelled lawnmower. More particularly, the disclosed subject matter relates to methods and apparatus that display a plurality of illuminating patterns based on the operating conditions of the lawnmower.

A lawnmower can include an electric motor, an internal combustion engine or a hybrid system that includes an electric motor and an internal combustion engine. The lawnmower can be propelled by at least a pair of wheels or by one or more pairs of tracks where each drive wheel/track is driven by a respective motor out of a pair of motors. These vehicles can include a pair of operator inputs—a respective one for each drive motor. The pair of operator inputs can permit an operator to control each drive motor individually to cause forward travel, reverse travel and facilitate turning of the vehicle. Each of the operator inputs can include a control lever and a mechanical linkage connected to the respective drive motor and control lever. Each mechanical linkage can transmit the direction of movement of the respective control lever to a mechanical actuator that translates the movement of the control lever into a drive direction (i.e., forward or reverse) and the magnitude of movement into a rotational speed at which the respective motor is driven. Driving the motors in the same direction and at the same speed can cause the vehicle to travel in a straight path. Driving the motors in the same direction but at different speeds can cause the vehicle to travel in a curved path. Driving one of the drive motors in a forward direction and the other drive motor in a reverse direction can permit the vehicle to spin about its yaw axis. A vehicle that can spin about its yaw axis can be referred to as a zero-turn-radius (“ZTR”) vehicle or a zero turn vehicle.

SUMMARY

Some embodiments are directed to a display system for a drive-by-wire lawnmower including a first motor and a second motor. The display system can include a first operator input configured to transmit a first motor signal, a second operator input configured to transmit a second motor signal, a first display mounted on the first operator input, a second display mounted on the second operator input, and a controller. The controller can be configured for electrical communication with the first motor, the second motor, and in electrical communication with the first operator input, the second operator input, the first display, and the second display. The controller can be configured to determine a respective drive speed and a respective drive direction for each of the first motor and the second motor based on both of the first drive signal and the second drive signal, and cause the first display and the second display to present a predetermined pattern based on the first motor signal and the second motor signal.

Some embodiments are directed to a display system for a lawnmower including a first motor and a second motor. The display system can include first operator handle, a second operator handle, and a controller. The first operator handle can be configured to transmit a first motor signal and include a first hand grip, a first display, and a first space spacing the first display away from the first hand grip. The second operator handle can be configured to transmit a second motor signal and include a second hand grip, a second display, and a second space spacing the second display away from the second hand grip. The controller can be configured to be in electrical communication with the first motor, the second motor and in electrical communication with the first operator input, the second operator input, the first display, and the second display. The controller is configured to determine a respective drive speed and a respective drive direction for each of the first motor and the second motor based on both of the first motor signal and the second motor signal, select from a plurality of display patterns that are different from each other based on the first motor signal and the second motor signal, and cause the first display and the second display to present a selected one of the display patterns.

Some embodiments are directed to a lawnmower that can include a frame, a mower deck, a first motor, a second motor, a first wheel, a second wheel, a first operator handle, a second operator handle, and a controller. The mower deck can be suspended from the frame and include at least one cutting chamber and at least one blade rotatably mounted in the cutting chamber. The first wheel can be connected to the frame and the first motor and the second wheel can be connected to the frame and the second motor. The first control lever can be pivotally mounted on the frame, configured to transmit a first motor signal, and include a first hand grip, and a first display. The second control lever can be pivotally mounted on the frame, configured to transmit a second motor signal, and include a second hand grip, and a second display. The controller can be in electrical communication with the first motor, the second motor, the first operator input, the second operator input, the first display, and the second display. The controller is configured to determine a drive speed and a drive direction for each of the first motor and the second motor based on both of the first motor signal and the second motor signal, cause the first motor and second motor to operate according to the drive speed and the drive direction, select from a plurality of display patterns that are different from each other based on the first motor signal and the second motor signal, and cause the first display and the second display to present a selected one of the display patterns.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

It can be advantageous to replace the mechanical linkage between the operator inputs and the respective drive motor with a drive-by-wire system in a vehicle, such as but not limited to a skid-steer vehicle, a tracked vehicle, or a lawnmower.FIG.1illustrates an embodiment of a drive-by-wire system10for a lawnmower12made in accordance with principles of the disclosed subject matter. The drive-by-wire system10can selectively operate in a first mode or in a second mode. The first mode can be configured to emulate a conventional mechanical linkage between the operator input and the respective drive motor. In the second mode, the drive-by-wire system10can simplify the input by the operator to cause the lawnmower12to travel in a straight path and easily allow the operator to maintain a straight path of travel regardless of the terrain over which the lawnmower12is travelling. Further, the drive-by-wire system10can improve operator comfort and reduce operator fatigue by automating certain operations, such as but not limited to auto-turning. In either the first mode or the second mode, the drive-by-wire system10can enhance safe operation, provide or enhance obstacle detection and avoidance, and provide or enhance emergency stopping capability. Further still, the drive-by-wire system10can be applied to a lawnmower12that is powered by an internal combustion engine as well as to a lawnmower12that is powered by a battery.

Some work vehicles, such as but not limited to lawnmowers, might lack an information display (also referred to as a dashboard or an instrument cluster or a combination meter or a meter) that provides the operator with information regarding the operating parameter(s) of the work vehicle. The drive-by-wire system10can include a display system200that is configured to present the operator with audible and/or visual information regarding the operational status of the lawnmower12such as but not limited to turning speed, turning direction, tilt angle, and obstacle location.

The display system200that can include at least one display device94that is configured to provide the operator with information indicative of operational conditions of the lawnmower12. For example, the display system200can convey with any one of plurality of predetermined patterns that respectively indicate a tilt condition, an obstacle detection condition, a turning condition, or a normal condition of the lawnmower12. A predetermined tilt warning pattern can indicate the severity of the tilt angle of the lawnmower12and the high side of the lawnmower12when the operational condition of the lawnmower12corresponds to a tilt condition. A predetermined obstacle warning pattern can indicate the relative distance and direction to an obstacle in or near the path of travel of the lawnmower12when the operational condition of the lawnmower12corresponds to the obstacle condition. A predetermined scrolling pattern can indicate the turning direction of the lawnmower12when the operational condition of the lawnmower12corresponds to the turning condition. A predetermined normal pattern can indicate that the operational condition of the lawnmower12does not merit special attention by the operator. Thus, the display system200can increase the operator's awareness of one or more operational parameter(s) of the lawnmower12.

FIG.2is a schematic representation of the lawnmower12ofFIG.1. Referring toFIGS.1and2collectively, the lawnmower12can include a main frame14, a mower deck16, a seat18, a pair of drive wheels20L,20R, a pair of caster wheels22L,22R and a pair of front forks24L,24R. The left drive wheel20L is obstructed from view inFIG.1. The drive-by-wire system10can include a controller26, a pair of control levers28,30, a pair of sensors and a32,34mode selector36.

Referring toFIG.1, the main frame14can support the seat18and the control levers28,30. The mower deck16can be suspended from the main frame14. Each of the drive wheels20L,20R can be connected to the main frame14. The main frame14can pivotally support the front forks24L,24R, and the front forks24L,24R can rotatably support the caster wheels22L,22R.

The mower deck16can be referred to as a deck, a deck assembly, a blade deck, a cutter housing, or a cutter housing assembly. Returning toFIGS.1and2collectively, the mower deck16can house a plurality of blades38and include a housing40, a discharge opening42, a discharge chute guard44and a plurality of wheel assemblies46. The wheel assemblies46can keep the mower deck16at a predetermined minimum height above the ground over which the lawnmower12traverses. Each blade assembly38can include one blade or a pair of blades rotationally offset with respect to one another. The housing40can include a plurality of cutting chambers48,50,52and each blade assembly38can rotate within its respective cutting chamber48or50or52. The discharge chute guard44can be pivotally mounted to the deck16adjacent to and above the discharge opening42.

Referring toFIG.2, the lawnmower12can include a power source54, a pair of hydrostatic transmissions (“HST”)56L,56R and a pair of driveshafts58L,58R. The power source54can include a drive output pulley60and each of the HSTs56L,56R can include an input pulley62. The lawnmower12can include a pair of idler pulleys64and a belt66that connects the output pulley60to the input pulleys62and passes along each of the idler pulleys64. One of the idler pulleys64can be mounted on a tension arm (not shown) so that the one of the idler pulleys64can maintain a predetermined tension on the belt66.

The power source54can include a second output pulley (not shown) and the mower deck16can include a plurality of driven pulleys (not shown) that are each rotationally connected to a respective one of the blade assemblies38. The second output pulley can be coaxial with the output pulley60. The driven pulleys can be coaxial with the respective one of the blade assemblies38and rotatably mounted on the top of the mower deck16. The mower deck16can include a blade drive belt (not shown) that is connected to the second output pulley and each of the driven pulleys.

The power source54can be an internal combustion engine, an electric motor or a hybrid of an internal combustion engine and an electric motor. The power source configured as an internal combustion engine or a hybrid power source can have the engine output axis oriented in the vertical direction V of the lawnmower12.

The HSTs56L,56R can have the same or similar structure and details of the HSTs56L,56R are described with respect to the right HST56R. The details of the left HST56L are omitted fromFIG.2for simplicity and clarity of the drawing. The right HST56R can include a hydraulic pump68, an actuator70, a hydraulic motor72and a pair of hydraulic lines74,76.

The pump68can be connected to and driven by a respective one of the input pulleys62. The hydraulic lines74,76can fluidly couple the pump68and the motor72such that hydraulic fluid flows out of the pump68, into and through the motor72, and returns to the pump68. The actuator70can be configured to cause the pump68to circulate the fluid to and from the motor72in a first direction, or in a second direction. The actuator70can terminate the flow of the hydraulic fluid between the pump68and the motor72. For example, when the pump68outputs fluid to the motor72via the first line74and the motor68returns the fluid via the second line76, the motor72can drive the right wheel20R in a forward direction. Conversely, when the pump68outputs fluid to the motor72via the second line76and the motor68returns the fluid via the first line74, the motor72can drive the right wheel20R in a reverse direction. The actuator70can be configured to cause the pump68to vary the flow rate of hydraulic fluid flowing into the motor72to vary the speed at which the motor72drives the right wheel20R. The motor72can be connected to and selectively drive the respective driveshaft58L,58R, which in turn, drives the corresponding wheel20L,20R in a forward direction or a reverse direction depending on an input from the respective one of the control levers28,30located adjacent the lawnmower's seat18. The belt66can be configured to provide a constant rotational input to the input pulleys62of each HST56L,56R. Thus, both the speed and the direction of rotation of each wheel20L,20R can be controlled by the controller26based on inputs to the sensors32,34via the control levers28,30. The controller26can be electrically connected to the actuator70of each of the HSTs56L,56R to cause the actuator70to selectively vary the speed and direction in which the fluid exiting the hydraulic pump68drives the hydraulic motor72. Each of the actuators70can include an electric, electronic or electro-mechanical servo that is connected to mechanical structure(s) that can vary the flow rate and which of the lines74,76the fluid exits the pump68. The servo can be any appropriate device such as but not limited to a rotary motor or a solenoid. The mechanical structure can be any appropriate structure such as but not limited to a swashplate or a valve body.

Referring toFIGS.1-3collectively, each of the control levers28,30and the respective one of the sensors32,34can be collectively referred to as an operator input78. Referring toFIGS.1and7, the display system200of the lawnmower12can include a display device94configured as a pair of display assemblies142,144that provide the operator with information indicative of the operational status of the lawnmower12. Each of the control levers28,30can include a handle79and the display assemblies142,144can be mounted on the respective handle79. The handle79can also be referred to as a hand grip or a grip and the control levers28,30can also be referred to as control handles, drive handles, or drive levers. The operator can use the control levers28,30to signal the controller26in which direction and at what speed the operator desires the controller26to cause the HSTs56L,56R to propel the lawnmower12. The operator can use the control levers28,30to signal the controller26to stop travel of the lawnmower12.

When the controller26drives both HSTs56L,56R in the same direction and at the same speed, the lawnmower12can travel in a straight path. When the controller26drives both of the HSTs56L,56R in the same direction but at different speeds, the lawnmower12can rotate about its yaw axis Y (FIG.2) in a clockwise direction or a counterclockwise direction from the perspective ofFIG.2so that the lawnmower12travels along a curved path. The curved path can include an arc of a circle whose radius is inversely proportional to the difference between the driving speeds of the HSTs56L,56R. When the controller26drives both of the HSTs56L,56R at the same speed but drives one of the HSTs56L,56R in a forward direction and the other of the HSTs56L,56R in a reverse direction, the lawnmower12can spin clockwise or counterclockwise about its yaw axis Y to provide a zero-radius turn. The operator can use the control levers28,30to signal the controller26to drive the lawnmower12straight in the forward direction or in the reverse direction, or turn while traveling in the forward direction or the reverse direction, or spin clockwise or counterclockwise.

The clockwise rotation of the lawnmower12while traveling in the forward direction or the reverse direction can also be referred to as a right turning direction from the perspective of the operator or the lawnmower12. The counterclockwise rotation of the lawnmower12while traveling in the forward direction or the reverse direction can also be referred to as a left turning direction from the perspective of the operator or the lawnmower12.

Referring toFIGS.1and3collectively, each of the control levers28,30can be pivotally connected to the main frame14, directly or indirectly, in any appropriate manner such that each of the control levers28,30can pivot independently about a respective pivot axis PA. Referring toFIG.3, each of the control levers28,30can pivot about the pivot axis PA and into a neutral position N, a first range R1and a second range R2. The neutral position N can be separate and spaced away from each of the first range R1and the second range R2. Each of the first range R1and the second range R2can include a plurality of positions for the control levers28,30. The control levers28,30can pivot from the neutral position N and into the first range R1in a direction that is away from the seat18, and from the neutral position N and into the second range R2in a direction that is toward the seat18. The control levers28,30can pivot between positions in the first range R1and the second range R2without stopping at the neutral position N.

Referring toFIGS.2and3, the sensors32,34can be in electrical communication with the controller26. The sensors32,34can be any appropriate sensor that can generate a signal that is indicative of the direction in which the respective I control ever28,30is pivoted by the operator and the magnitude of the movement of the respective control lever28,30by the operator. For example, each of the sensors32,34can be a potentiometer, rotary Hall-effect sensor, encoder, or other angle position sensor.

Referring toFIGS.1-3collectively, each of the sensors32,34can be configured to generate a signal and transmit the respective signal to the controller26. The signals can include data indicative of the position of the respective control lever28,30with respect to a first range R1, a second range R2and a neutral position N. The controller26can be configured to determine a speed and a direction of travel requested by the operator of the lawnmower12from the signal data. The controller26can be configured to process the signal data in accordance with a first process when the controller26operates in the first mode and in accordance with a second process when the controller26operates in the second mode.

Referring toFIG.4, the drive-by-wire system10can be selectively operated in the first mode or the second mode based on a selection made by an operator of the lawnmower12using the mode selector36. The mode selector36can be mounted at any appropriate location on the lawnmower12that is within a suitable reach distance from the operator when the operator is seated in the seat18. In the exemplary embodiment ofFIG.1, the mode selector36can be mounted on a control panel80located adjacent to or on the right fender82of the lawnmower. The mode selector36can be any appropriate type of switch such as but not limited to a rotary dial, a rotary knob, a toggle switch, at least one push button, a magnetic position sensor, at least one touch sensor, or an icon on a touch screen.FIG.4illustrates the mode selector36as a rotary dial that can be moved between a Mode1position and a Mode2position.

Returning toFIG.2, the mode selector36can be in electrical communication with the controller26. The mode selector36can be configured to output a first signal when in the Mode1position and a second signal that is different from the first signal when in the Mode2position. The drive-by-wire system10can operate in the first mode when the controller26receives the first signal from the mode selector36and in the second mode when the controller26receives the second signal from the mode selector36.

FIG.5illustrates operations of the control levers28,30when the drive-by-wire system10operates in the first mode. The display device94has been omitted fromFIG.5for clarity and simplicity of the drawing. The controller26can be configured to operate in the first mode such that the controller26controls the right HST56R based only on the signal received from the right sensor32and the left HST56L based only on the signal received from the left sensor34. That is, the controller26can control the right HST56R independently from the signals received from the left sensor34and the left HST56L independently from the signals received from the right sensor32.

Specifically, the first range R1can correspond to a forward direction of travel of the lawnmower12and the second range R2can correspond to a reverse direction of travel of the lawnmower12. The controller26can be configured to drive the right HST56R in the forward direction when the right control lever28is in the first range R1and in reverse direction when the right control lever28is in the second range R2. The controller26can be configured to drive the left HST56L in the forward direction when the left control lever30is in the first range R1and in reverse direction when the left control lever30is in the second range R2. If the operator moves the control levers28,30into different relative positions in the first range R1, the controller26can drive both of the HSTs56L,56R in the forward direction but at different speeds, where the speed of each of the HSTs56L,56R corresponds to the position of the respective one of the control levers28,30in the first range R1. If the operator moves the control levers28,30into different relative positions in the second range R2, the controller26can drive both of the HSTs56L,56R in the reverse direction but at different speeds, where the speed of each of the HSTs56L,56R corresponds to the position of the respective one of the control levers28,30in the second range R2.

The controller26can be configured to determine a neutral condition and cause the HSTs56L,56R to idle when a respective one of the control levers28,30is in the neutral position N. The lawnmower12can come to a stop when both of the HSTs56L,56R are caused to idle.

The controller26can be configured to drive one of the HSTs56L,56R in the forward direction and the other of the HSTs56L,56R in the reverse direction when the respective one of the control levers28,30is in the first range R1and the other of the control levers28,30is in the second range R2. If both control levers28,30are placed at the same position while in opposite ranges R1, R2, the controller26can drive the HTSs56L,56R to spin the lawnmower12about its yaw axis Y. However, any variation the positions of the control levers28,30can cause the lawnmower12to deviate from a zero-turn-radius. Thus, it can be difficult for an operator to maintain a precise zero-turn-radius in the first mode of the drive-by-wire system10.

Accordingly, the first mode can emulate the operation of mechanically linked control levers of a conventional ZTR lawnmower. Further, the first mode of the drive-by-wire system10can mimic some or all of the deficiencies described above with respect to a conventional ZTR lawnmower.

FIG.6illustrates operations of the control levers28,30when the drive-by-wire system10operates in the second mode. The display device94has been omitted fromFIG.6for clarity and simplicity of the drawing. The drive-by-wire system10can be configured to operate in the second mode such that the right control lever28controls the travel speed and the forward direction of travel and reverse direction of travel of the lawnmower12and the left control lever30controls the steering direction of the lawnmower12. Further, the second mode of the drive-by-wire system10can provide precise or nearly precise zero-turn-radius operation using one of the control levers28,30. That is, the drive-by-wire system10can be configured to select one drive condition from a plurality of drive conditions that include a straight travel condition, a normal turn condition, and a zero-turn-radius condition. Thus, the second mode can relieve the operator of precise control of both of the control levers28,30when the operator desires a precise or nearly precise straight line tracking or a zero-turn-radius operation.

Specifically, in the second mode, the controller26can select the straight condition in which the controller26is configured to drive both HSTs56L,56R in the forward direction and at the same speed when the right control lever28is in the first range R1and the left control lever30is in the neutral position N shown inFIG.3. Further, the controller26can be configured to drive both HSTs56L,56R in the reverse direction and at the same speed when the right control lever28is in second range R2and the left control lever30is in the neutral position N shown inFIG.3. The controller26can be configured to set the same speed for both HSTs56L,56R based on the position of the right control lever28in the first range R1or the second range R2. That is, the operator can use a single one of the control levers28,30to control both HSTs56L,56R simultaneously. Thus, the drive-by-wire system10can provide a straight line tracking function using only the right control lever28. This feature can allow an operator to more precisely control the speed of the lawnmower12without deviating from the straight line path of the lawnmower12.

Further, in the second mode, the controller26can select the normal turn condition in which the controller26drives both of the HSTs56L,58R in the same direction but at different speeds, thereby allowing the operator to steer the lawnmower12along the desired curved path. When traversing a curved path, one of the wheels20L,20R follows an inner curve (or circle) and the other of the wheels20L,20R follows an outer curve (or circle). The one of the wheels20L,20R that follows the inner curve can be referred to as an inside wheel and the corresponding one of the HSTs56L,56R can be referred to as the inside motor. The one of the wheels20L,20R that follows the outer curve can be referred to as an outside wheel and the corresponding one of the HSTs56L,56R can be referred to as the outside motor. The controller26can be configured to determine the right HST56R is the inside motor and the left HST56L is the outside motor when the left lever30is in the first range R1shown inFIG.3. The controller26can be configured to determine the right HST56R is the outside motor and the left HST56L is the inside motor when the left lever30is in the second range R2shown inFIG.3.

The controller26can be configured to determine an outside wheel speed that directly correlates to the position of the right control lever28and a speed reduction amount that directly correlates to the position of the left control lever30. That is, the operator can set the speed of the turn with the right control lever28and the direction of the turn with the left control lever30. The controller26can be configured to determine an inside wheel speed by subtracting the speed reduction amount from the outside wheel speed.

For example, each of the ranges R1, R2for the left control lever30can include a normal turn range that extends from the respective one of the minimum speed locations R1min, R2min to a respective one of a first zero-turn location R1zand a second zero-turn location R2zshown inFIG.3. The zero-turn locations R1z, R2zcan be spaced away from the respective one of the maximum speed locations R1max, R2max by a predetermined angle that can provide a desired zero-turn-radius operation of the lawnmower12. The outside wheel speed can increase as the right control lever28moves from the first minimum speed position R1min or the second minimum speed position R2min to the first zero-turn location R1zor the second zero-turn location R2z, respectively. The speed reduction amount can increase as the left control lever30moves from the first minimum speed position R1min or the second minimum speed position R2min to the first zero-turn location R1zor the second zero-turn location R2z, respectively. That is, the radius of the curved path of the lawnmower12can decrease as the speed reduction amount increases.

Returning toFIG.3, the controller26can be configured to, in this second mode, execute a zero-radius turn when the left lever30is placed in a location that is between and inclusive of the first zero turn location R1zand the first maximum speed location R1max for a clockwise zero-radius turn or in a location that is between and inclusive of second zero turn location R2zand the second maximum speed location R2max for a counterclockwise zero-radius turn. The controller26can be configured to drive both of the HSTs56L,56R at the same speed but drive the right HST56R in the reverse direction and the left HST56L in the forward direction when the left control lever30is in any position from the first zero turn location R1zto the first maximum speed location R1max and the right control lever28is in any location in either the first range R1or the second range R2. This can result in a clockwise zero-turn-radius spin of the lawnmower12in the frame of reference ofFIG.6. Further, the controller26can be similarly configured to cause the lawnmower12execute a counterclockwise zero-turn-radius spin when the left control lever30any position from the second zero turn location R2zto the second maximum speed location R2max and the right control lever28is in any location in either the first range R1or the second range R2. Thus, the second mode of the drive-by-wire system10can provide precise or nearly precise zero-turn-radius operation of the lawnmower12using only the left control lever30.

The controller26can be configured to terminate the zero-turn-radius operation of the lawnmower12if the operator moves left control lever30out of the range of positions between the first zero turn location R1zand the first maximum speed location R1max or between the second zero turn location R2zand the second maximum speed location R2max. This permits the operator to stop the zero-radius turn and resume a straight path operation or normal turn operation by manipulating only one of the two control levers28,30, which operation can be the same as or similar to operation of a conventional zero-turn-radius lawnmower.

Further, the controller26can be configured to cause both HSTs56L,56R to idle when the right control lever28is in the neutral position. This can permit the operator to bring the lawnmower to a stop by manipulating only one of the two control levers28,30, as compared to operating both levers of a conventional lawnmower in order to stop the conventional lawnmower.

FIG.7illustrates a first embodiment of the display device94that includes the right display assembly142and the left display assembly144. The right display assembly142can include a right housing146, a right light strip148and the left display assembly144can include a left housing150and a left light strip152. The handles79can be incorporated into the housings146,150. The housings146,150can support the respective one of the light strips148,152on the respective one of the levers28,30. The light strips148,152can include a plurality of color light emitting diodes (“LEDs”) distributed along the length of the light strips148,152.

The right housing144can include a right outer support154, and right inner support156and a right frame158that extends from and is connected each of the supports154,156. The supports154,156can be cantilevered to the handle79of the right control lever28and the frame158can extend from and be connected to the supports154,156such that the frame158is spaced away from the handle79by a predetermined distance that can permit an operator to extend a hand between the frame158and the handle79. The right light strip148can include an outer end160and an inner end162. The right light strip148can be mounted in and surrounded by the right frame158.

The left housing150can include a left outer support164, and left inner support166and a left frame168that extends from and is connected each of the supports164,166. The supports164,166can be cantilevered to the handle79of the left control lever30and the frame168can extend from and be connected to the supports164,166such that the frame168is spaced away from the handle79by a predetermined distance that can permit an operator to extend a hand between the frame168and the handle79. The light strip152can include an outer end170and an inner end172. The left light strip152can be mounted in and surrounded by the left frame168.

FIG.8shows a second embodiment of the display device94that includes a left display assembly174that is mounted on a left control lever176, where the left control lever176can be structured and operated in the manner described above with respect to the left control lever30. The left display assembly174can include a left housing178and a left light strip180. The housing178can support the light strip180on the lever176. The light strip180can include a plurality of color light emitting diodes (“LEDs”) distributed along the length of the light strip180.

The left housing178can include a handle182, an outer support184, an inner support186and a frame188that extends from and is connected each of the supports184,186. The supports184,186can be cantilevered to the handle182and the frame188can extend from and be connected to the supports184,186such that the frame188is spaced away from the handle182by a predetermined distance that can permit an operator to extend a hand (shown in phantom) between the frame188and the handle182. The light strip180can include an outer end190and an inner end192.

The frame188can include a curved portion194that extends from the outer support186to the outer end190. The curved portion194can follow along a curved portion202of the left control lever176. The left display strip180can be mounted in the frame188.

The display device94shown inFIG.8can also include a right display assembly that includes the structures of the left display assembly174, except the right display assembly can be a mirror image of the left display assembly174and does not include the auto-turn switches196,198. The left control lever176and the mirror image right control handle can include all of the features and perform all of the operations described above with respect to the control levers28,30ofFIGS.1-7.

Referring toFIG.9, a third exemplary embodiment of the display device94can include light strips232,234that are integrated directly into a right control lever228and a left control lever230. The control levers228,230ofFIG.9can include all of the features and perform all of the operations described above with respect to the control levers28,30ofFIGS.1-7. Each of the light strips232,234can include a plurality of color light emitting diodes (“LEDs”) distributed along the length of the light strips232,234. The right light strip232can include a right outer end236and a right inner end238. The left light strip234can include a left outer end240and a left inner end242.

Illumination control of the light strips180,232,234can be same as that for the light strips148,152. Connections within the display system200and operations of the light strips180,232,234will be described with reference to the light strips148,152.

FIG.10is a schematic view showing the electrical power distribution and electrical signal communication for the drive-by-wire system10. The drive-by-wire system10can include at least one battery96, a directly processed sensor array98, a user interface100, an external motor control system102, a distributed processing system104and an externally processed sensor array106. The display system200can be in electrical communication with the battery96and include the controller26, the directly processed sensor array98, the user interface100, the distributed processing system104and the externally processed sensor array106.

The external motor control system112can include a right HST controller122and a left HST controller124. Instead of the controller26being directly connected to the actuator70as shown inFIG.2, the controller26can send drive commands to the right HST controller122and to the left HST controller124that are based on the signals received from the sensors32,34. The controllers122,124can be configured to signal the respective actuator70as described above with respect toFIGS.1-8.

AlthoughFIG.10appears to show two batteries96, the battery96ofFIG.10can be a single battery96with the second location of the battery96illustrated to simplify the electric power distribution paths between the battery96and each of the electric/electrical devices of the drive-by-wire system10. However, alternate embodiments can include a second battery96that is dedicated to the external motor control system102.

The controller26can be in electrical power communication with the battery96. The controller26can distribute power from the battery96to each of the directly processed sensor array98, at least one audio device92of the user interface100, the distributed processing system104and the externally processed sensor array106. The battery96can supply power directly to the external motor control system102and at least one display device94of the user interface100.

The controller26can be in electrical signal communication directly with each of the directly processed sensor array98, the audio device(s)92, external motor control system102and the distributed processing system104. The controller26can be in electrical communication indirectly with the display device(s)94and the externally process sensor array106by way of the distributed processing system104. The electrical communication to and from the controller26can use analog signals or digital signals or a combination of analog signals and digital signals.

The directly processed sensor array98can include the sensors32,34, the mode selector36, auto-turn switches84,86(or auto-turn switches196,198ofFIG.8), wheel speed sensors88and a dynamic sensor array90. The wheel speed sensors88can send analog communication signal(s) to the controller26that are indicative of the rotational speed of the respective one of the drive wheels20L,20R. The dynamic sensor array90can send digital communication signal(s) to the controller26that are indicative of the dynamic acceleration(s) acting on the lawnmower12and the rotation rate(s) that the lawnmower12is experiencing. The sensors32,34can send analog communication signals as described above, the mode selector36and the switches84,86can send digital communication signals as described above, and the RC remote can send analog and/or digital communication signals as appropriate to achieve the desired performance of the lawnmower12. The controller26can be configured to distribute electrical power from the battery to the sensors32,34, the mode selector36, the switches84,86(or switches198,198), the wheel speed sensors88and the sensor array90.

The drive-by-wire system10can be configured to operate the lawnmower12at a remote distance from the lawnmower12that is within a predetermined range. The directly processed sensor array98can include a remote control unit (also referred to as an RC unit or as an RC remote) that is configured to mimic the signals of the sensors32,34, the mode selector36and the auto-turn switches84,86(or the auto-turn switches196,198ofFIG.8) so that the operator to control the lawnmower12from the remote distance. The remote control unit can be a feature of the directly processed sensor array.

The display system200can be configured to provide audible and/or visual information or messages to the operator of the lawnmower12. The user interface100can include at least one audio device92and at least one display device94that can alert the operator of at least one predetermined operating condition of the lawnmower12. The audio device92can include, but is not limited to, a speaker, a horn, and/or an alarm buzzer. The display device94can include, but is not limited to, at least one LED, a liquid crystal display screen, and/or a touch screen. The controller26can be configured to cause the audio device92to emit at least one audio message(s) and the display device94to display at least one visual message when the controller26is in the first mode or in the second mode. The controller26can be configured to transmit an analog communication signal directly to the audio device(s)92.

The distributed processing system104can include an operator LED indicator driver unit108. The controller26can be in electrical communication with the driver unit108such that the controller26can selectively supply power from the battery96to the driver unit108and send a display command signal to the driver unit108. The controller26can be configured to determine the display command for the display device(s)94based on data the controller26receives from the directly processed sensor array98. The controller26can be configured to send the display command signal as a digital communication signal to the driver unit108.

The operator LED indicator driver unit108can be configured to process the display command signal received from the controller26and issue an appropriate one of an illumination signal and off signal to the display device94. The illumination signal can be a digital communication signal. The controller26can be configured to send one of a plurality of different display command signals and the unit108can be configured to send one of a plurality of different illumination signals that correspond to the plurality of different display command signals, respectively.

It can be advantageous to provide visual messages, alone or in combination with audio messages, to the operator of the lawnmower12that can improve or enhance a safe and efficient operation of the lawnmower12. For example, it can be advantageous to provide a visual message that can indicate a tilt condition of the lawnmower12, or an obstacle condition in the path of the lawnmower12, or a turn condition of the lawnmower12. The controller26can be configured to determine an appropriate predetermined pattern from a plurality of predetermined patterns and to cause the display device94to present the appropriate predetermined pattern based on the drive signal(s) received from the directly processed sensors98and the distributed processing system104. Each of the predetermined patterns can have a unique shape, unique size, and/or unique color, and can be a static pattern that does not change is size shape or location or a dynamic pattern that changes in at least one of a size, shape and location.

FIG.11illustrates an exemplary display control algorithm that the controller26can follow to control the operation of the display device94based on the current operating condition of the lawnmower.FIGS.12-14illustrate exemplary subroutines of the algorithm ofFIG.11. The controller26can be configured to start the display control algorithm at step S100and subsequently move to step S102.

Referring toFIG.15, the lawnmower12can be operated on uneven terrain, including along an inclined surface S that is inclined at a tilt angle θ with respect to horizontal. At step S102, the controller26can be configured to determine the tilt angle θ from data received from the dynamic sensor array90and compare the tilt angle θ with a predetermined first warning threshold T1. If the controller26determines that the tilt angle θ is greater than the first warning threshold T1, then the controller26can be configured to proceed to step S104where the controller26can determine a tilt condition presently exists for the lawnmower12and perform a tilt display control of the display device94according to the tilt display control subroutine ofFIG.12. Upon executing the tilt display control subroutine, the controller26can be configured to proceed to step S106and exit the display control algorithm.

If the controller determines at step S102that the tilt angle θ is less than or equal to the first warning threshold T1, then the tilt angle θ of the lawnmower12can be considered to be within a desired range for operation of the lawnmower12and the controller26can proceed to step S108to determine whether another one of the plurality of predetermined patterns (also referred to as display messages) might be appropriate for the current operational condition of the lawnmower12.

Returning toFIG.10, the drive-by-wire system10can include an obstacle detection and avoidance system. The obstacle detection and avoidance system can operate in the first mode and in the second mode of the drive-by-wire system10described above with respect toFIGS.3-7. The obstacle detection and avoidance system can include the controller26, the externally processed sensor array106and the distributed processing system104. At step S108, the controller26can be configured to initiate processing that determines whether an obstacle is presently in or near a reverse travel path of the lawnmower12. The controller26can be configured to determine whether the lawnmower12is traveling in a reverse direction using the signals received from the sensors32,34, as described above with respect toFIGS.3-7. If the controller26determines that the lawnmower12is presently traveling in the reverse direction, the controller26can proceed to step S110to determine whether an obstacle is present within a predetermined area of the lawnmower12.

Returning toFIG.10, the distributed processing system104can include an ultrasonic/LiDAR processing unit110and a vision system processing unit112, and the externally processed sensor array106can include a LiDAR sensor114, an ultrasonic sensor116and a camera sensor118. In an alternate embodiment, the distributed processing system104can include a RADAR sensor and processing unit in place of one or both of the units110,112or in addition to both units110,112. The distributed processing system104can be configured to process the data received from the externally processed sensor array106and output one or more signals to the controller26. The controller26can be configured to determine whether an obstacle is present in or near the path of travel of the lawnmower12based on the signal(s) received from the distributed processing system104.

If the controller26determines that an obstacle presently exists in or near the reverse travel path of the lawnmower12at step S110, the controller26can be configured to proceed to step S112where the controller26can determine an obstacle condition presently exists for the lawnmower12and perform an obstacle display control subroutine. The obstacle display control subroutine will be discussed with reference toFIG.13. After executing the obstacle display control subroutine, the controller26can proceed to step S106and exit the display control algorithm.

If the controller26determines that no obstacle presently exists in or near the reverse travel path of the lawnmower12, then the controller26can proceed to step S114. At step S114, the controller26can be configured to determine a clear path condition and proceed to step S116.

At step S116, the controller26can be configured to perform a normal display control subroutine. The normal display control subroutine can display any appropriate predetermined pattern that indicates to the operator that the lawnmower12is operating in a manner that does not merit special attention by the operator. The predetermined pattern of the normal display control subroutine can include a predetermined pattern, such as but not limited to, a static illumination of one or more of the LEDs of the display device94, and a predetermined color, such as but not limited to, white. The controller26can be configured to signal the operator LED indicator driver unit108to cause the display devices(s)94to display the predetermined pattern in accordance with the normal display control. Alternate embodiments can turn off the display device94or illuminate a static green-colored pattern.

After executing the normal display control, the controller26can proceed to step S106and exit the display control algorithm.

If the controller26determines at step S108that the lawnmower12is not traveling in a reverse path, the controller26can be configured to proceed to step S118. At step S118, the controller26can determine whether the lawnmower12is turning, either by manual control performed by the operator or by an automated turning operation performed by the controller26.

If the controller26determines at step S118that the lawnmower12is turning, then the controller26can be configured to proceed to step S120. At step S120, the controller26can be configured to determine that a turn condition or an automated turn condition presently exists for the lawnmower12and can perform a turn display control. A turn display control subroutine will be described with respect toFIG.14. After executing the turn display control subroutine, the controller26can be configured to proceed to step S106and exit the display control algorithm.

If the controller determines at step S118that the lawnmower12is not turning, the controller26can proceed to step S122. At step S122, the controller26can be configured to determine that a straight condition presently exits for the lawnmower12. The controller26can be configured to proceed from step S122to step S116and perform the normal display control subroutine as described above. Upon execution of the normal display control, the controller26can be configured to proceed to step S106and exit the display control algorithm.

FIG.12shows a flowchart that depicts an exemplary tilt display control subroutine that can be executed by the controller26for operating the display device94to express a tilt warning pattern to the operator of the lawnmower12. The tilt warning pattern can be indicative of the lawnmower's12tilt attitude relative to horizontal. During the execution of step S104ofFIG.11, the controller26can initiate the tilt display control subroutine at step S124ofFIG.12. The controller26can be configured to move from step S124to step S126.

The display system200can be configured to display the tilt warning pattern for a predetermined range of tilt angles θ in an effort to provide the operator with reasonable and useful notice of a particular tilt condition of the lawnmower12so that the operator can take appropriate measure(s) to change the tilt angle θ of the lawnmower12. For example, the operator LED indicator driver unit108can be configured to signal the display94to illuminate a predetermined color, such as but not limited to red, and in a predetermined pattern, such as but not limited to a flashing pattern. The tilt warning pattern can include a low side pattern and a high side pattern that is different from the low side pattern. In exemplary embodiments, the high side pattern can be larger in area than the low side pattern, and/or a brightness that is greater than the brightness of the low side pattern, and/or a darker shade of the predetermined color as compared to the low side pattern.

The display system200can be configured to vary the tilt warning pattern based on the current tilt angle θ of the lawnmower12. For example, the flashing pattern can increase in frequency as the tilt angle θ approaches a second warning threshold T2and decrease in frequency as the tilt angle θ decreases relative to the second warning threshold T2. The controller26can be configured to generate an audio command that causes the audio device92to emit a sound pulse at increasing frequencies and decreasing frequencies in accordance with the corresponding increasing flashing frequency and decreasing flashing frequency. The controller26can be configured to signal the audio device92to emit a continuous sound when the tilt angle θ is equal to or greater than the second warning threshold T2.

At step S126, the controller26can be configured to compare the tilt angle θ to the predetermined second warning threshold T2, where second warning threshold T2is greater than the first warning threshold T1. If the controller26determines that the tilt angle θ is greater than or equal to the second warning threshold T2, then the controller26can proceed to step S128.

The second warning threshold T2can be set an any appropriate value that can indicate a limit of desirable operation of the lawnmower12on the inclined surface S. When the tilt angle θ is greater than or equal to the second warning threshold T2, the controller26can be configured to set up a display command that will cause the display device94to present a constant light pattern that does not flash and an audio command that will cause the audio device92to emit a constant tone. The controller26can be configured to move from step S128to step S134.

If the controller26determines at step S126, that the tilt angle θ is less than the second warning threshold T2, then the controller26can proceed to step S130.

At step S130, the controller26can be configured to determine the value of a difference A between the second warning threshold T2and the tilt angle θ. The difference A can be used to determine the flash frequency for the light pattern and the pulse frequency for the audio tone. For example, the controller26can be configured to access a look-up table that pairs individual values of the difference A (or a predetermined range of values of the difference A) with a corresponding pulse frequency for each of the light pattern and the audio tone. Alternate embodiments can include a controller26that is configured to calculate a pulse frequency for the light pattern and the audio tone based on one or more predetermined equations in which the difference A is a variable. Subsequently, the controller26can proceed to step S132.

At step S134, the controller26can be configured to determine which side of the lawnmower12is the high side. The controller26can be configured to process the data from the dynamic sensor array90in any appropriate manner in order to determine the direction and magnitude of the tilt angle θ of the lawnmower12.

If the controller26determines that the tilt angle θ of the lawnmower12indicates that the left side of the lawnmower12is the high side, then the controller26can proceed to step S136. At step S136, the controller26can be configured to prepare and send a display command signal to the operator LED indicator driver unit108that the left side of the lawnmower12is the high side. The operator LED indicator driver unit108can, in turn, send a command to the display device94to cause the display device94to display the high side pattern on the left light strip152and the low side pattern on the right light strip148. Then, the controller26can proceed to step S138and end the tilt display control subroutine.

If the controller26determines at step S134that the tilt angle θ of the lawnmower12indicates that the right side of the lawnmower12is the high side, then the controller26can proceed to step S140. At step S140, the controller26can be configured to prepare and send a display command signal to the operator LED indicator driver unit108requesting a high side pattern for the right light strip148and the low side pattern for the left light strip152. The operator LED indicator driver unit108can, in turn, send a command to the display device90to cause the display device94to display the high side pattern on the right light strip148and the low side pattern on the left light strip152. Then, the controller26can proceed to step S138and end the tilt display control subroutine.

The display system200can be configured to determine whether an object is in or near a path of travel of the lawnmower12when the lawnmower is traveling in a reverse direction and notify the operator of the presence or absence of an object near or in the reverse path of travel. The controller26can be configured to limit the travel speed of the lawnmower12, signal the HSTs56L,56R to reduce the travel speed of the lawnmower12, or signal the HSTs56L,56R to stop the travel of the lawnmower10based on signals the controller26receives from the ultrasonic/LiDAR processing unit110and the vision system processing unit112. The controller26can be configured to send an audio command to the audio device92and a display command to the operator LED indicator driver unit108based on the signals the controller26receives from the ultrasonic/LiDAR processing unit110and the vision system processing unit112to cause the audios device92to emit a predetermined audio message and the display device94to illuminate with a predetermined color and a predetermined pattern in accordance with the obstacle display control subroutine shown inFIG.13. The controller26can be in electrical communication with the ultrasonic/LiDAR processing unit110and the vision system processing unit112such that the controller26can selectively supply power from the battery96to the units110,112and receive a first object location signal and a second object location signal from the units110,112, respectively.

Referring toFIGS.16and17, the sensors114,116,118can be mounted at different locations on the rear end120of the lawnmower12. The LiDAR sensor114and/or the ultrasonic sensor116can be configured to scan a predetermined scan two-dimensional plane that extends outwardly from the rear end120of the lawnmower12and is spaced above ground level by a predetermined distance. The scan plane can include at least a predetermined detection zone Z that extends out from the rear end120of the lawnmower12. The LiDAR sensor114and the ultrasonic sensor116can be configured to send a first data signal and a second data signal, respectively, that can include information that is indicative of the physical location of one or more objects located in the field of view of the sensors114,116. For example, the first data signal from the LiDAR sensor114can include data in a polar format (angle and radius). The first data signal and the second data signal can be configured as a point array or a data array.

The LiDAR sensor114and the ultrasonic sensor116can be in electrical communication with the ultrasonic/LiDAR processing unit110such that the ultrasonic/LiDAR processing unit110can selectively supply power from the controller26to the LiDAR sensor114and ultrasonic sensor116, the LiDAR sensor114can send the first image signal to the ultrasonic/LiDAR processing unit110, and the ultrasonic sensor116can send the second image signal to the ultrasonic/LiDAR processing unit110. The first image signal can be a digital communication signal and the second image signal can be analog communication signal.

The ultrasonic/LiDAR processing unit110can be configured to determine a first detection command based on the first image signal and send the first detection signal to the controller26. The vision system processing unit112can be configured to determine a second detection signal based on the second image signal and send the second detection signal to the controller26. The first and second detection signals can be digital communication signals. The first detection signal and the second detection signal can include data that is indicative of the location of any object(s) detected in the field of view of the sensors114,116.

The controller26can be configured to determine a reverse travel state of the lawnmower12when the first and second direction signals indicate that at least the right control lever28is in the second range R2as described above with respect toFIGS.5and6. The controller26can be configured to supply power to the ultrasonic sensor/LiDAR processing unit110and the vision system processing unit112when the controller26determines the reverse travel state and terminate the supply of power to the units110,112when the controller26determines that the lawnmower12is not in the reverse travel state.

The controller26can be configured to divide the detection zone Z into a predetermined warning zone Z1and predetermined stop zone Z2. The controller26can be configured to determine whether the location data included with the first detection signal or the second detection signal lies within the warning zone Z1or the stop zone Z2. If the controller26determines that the first detection signal or the second detection signal includes location data that lies within the warning zone Z1, the controller26can be configured to reduce a maximum speed limit for the HSTs56L,56R and/or send a drive signal to the HSTs56L,56R that causes the HSTs56L,56R to reduce their drive speed. If the controller determines that the first detection signal or the second detection signal includes location data that lies within the stop zone Z2, the controller26can be configured to ignore any movement of the control levers28,32in the second region R2by the operator and signal the HSTs56L,56R to stop the lawnmower12.

AlthoughFIGS.16and17show the zones Z, Z1, Z2as having a rectangular shape, exemplary embodiments can include zones Z, Z1, Z2that have a semicircular shape, or square shape, or other shape, where the warning zone Z1and the stop zone Z2have a width that corresponds to the width of the lawnmower12measured at the drive wheels20L,20R. The square or rectangular shape for the zones Z, Z1, Z2can be advantageous when the lawnmower12travels in a reverse direction next to a building or house. The lateral edges of the zones Z, Z1, Z2can extend parallel or substantially parallel to the exterior of the building or house. Thus, the exterior of the building or house can be outside of the zones Z, Z1, Z2and a false obstacle detection caused by the building or house can be avoided.

The directly processed sensor array98of the drive-by-wire system10can include an operator input that can allow the operator of the lawnmower to adjust the boundary of the zones Z1, Z2. For example, the operator input can permit the operator of the lawnmower12to toggle between the rectangular shape of the zones Z1, Z2sons inFIGS.16and17and the semi-circular shape of the zones Z1, Z2described above. As another example, the operator input can permit the operator of the lawnmower12to change the width and/or the length (or radius and arclength) of the zones Z1, Z2.

ComparingFIGS.16and17, the controller26can be configured to adjust the size of the warning zone Z1and the stop zone Z2based on the second detection signal received from the vision system processing unit112. The zones Z1, Z2ofFIG.17are bigger than the zones Z1, Z2ofFIG.16. The second detection signal can include information that is indicative of the presence of predetermined object such as but not limited to a human. The controller26can be configured to compare the location data to the larger zones Z1, Z2shownFIG.17when the second detection signal includes information that is indicative of the presence of the predetermined object. The controller26can be configured to compare the location data to the smaller warning zone Z1and the stop zone Z2shown inFIG.16when the second detection signal does not include information that is indicative of the presence of the predetermined object.

The controller26can send an audio command to the audio device92and/or a display command to the operator LED indicator driver unit108when the controller26determines that the first detection signal or the second detection signal includes location data that lies within the warning zone Z1.FIG.13shows a flowchart that depicts an exemplary obstacle display control subroutine that can be executed by the controller26for operating the display device(s)94to express an obstacle warning pattern to the operator of the lawnmower12. The obstacle warning pattern can be indicative of on object in or near the path of travel of the lawnmower's12when the lawnmower12is traveling in the reverse direction. During the execution of step S112ofFIG.11, the controller26can initiate the obstacle display control subroutine at step S142ofFIG.13. The controller26can be configured to move from step S142to step S144.

At step S144, the controller26can be configured to determine whether there is an object in the stop zone Z2based on the signals the controller26receives from the distributed processing array104. If the controller26determines that there is an object in the stop zone Z2, then the controller26can proceed to step S146.

At step146, the controller26can be configured to set up a display command for the operator LED indicator driver unit108that instructs the operator LED indicator driver unit108to flash at a predetermined frequency the display device94in a predetermined color such as, but not limited to, yellow. The controller26can be configured to move from step S146to step S148and exit the obstacle display control subroutine.

If the controller26determines at step S144that an object is not present in the stop zone Z2, the controller26can be configured to move to step S150. At step S150, the controller26can be configured to determine whether there is an object in the warning zone Z1based on the signals the controller26receives from the distributed processing array104. If the controller26determines that there is an object in the warning zone Z1, then the controller26proceed to step S152.

At step152, the controller26can be configured to determine whether the object that has been detected in the warning zone Z1is offset relative to the path of travel of the lawnmower12or located directly in the path of travel of the lawnmower12. For example, if the detected object is in the path of travel of both of the rear wheels20L,20R or located between the paths of both of the rear wheels20L,20R, then the objected can be described as a centered object. If the detected object is in or near the path of travel of one of the rear wheels20L,20R but not in or near the path of travel of the other one of the rear wheels (20L,20R, then the detected object can be described as an offset object. The detected object also can be described as an offset object if the object is outside the path of travel of both of the rear wheels20L,20R and still within the detection zone Z if the detection zone Z is wider than the track of the rear wheels20L,20R.

The controller26can be configured to determine whether the detected object is a centered object or an offset object based on the signals the controller26receives from the distributed processing system104. If the controller26determines that the detected object is an offset object, the controller26can move to step S154. If the controller26determines that the detected object is a centered object, the controller26can move to step S156.

At step154, the controller26can be configured determine an offset condition and set up a display command for the operator LED indicator driver unit108that instructs the operator LED indicator driver unit108to cause the display device94to display a near side obstacle pattern and a far side obstacle pattern that is different from the near side obstacle pattern. For example, the near side pattern can have a size that is larger than a corresponding size of the far side. The size can be measured as an area, a length, a width, or a diameter.

The controller26can be configured to determine which side of the lawnmower12is the near side and which side is the far side in any appropriate manner based on the signals received from the distributed processing system104. For example, the controller26can be configured to determine whether the detected object is closer to the left rear wheel20L or the right rear wheel20R. The near side can correspond to the closer of the two rear wheels20L,20R and the far side can correspond to the farther of the rear wheels20L,20R. If the controller26determines that the left side is the near side, the controller26can be configured to signal the operator LED indicator driver unit108to cause the left light strip152to display the near side obstacle pattern and the right light strip148to display the far side obstacle pattern. If the controller26determines that the right side is the near side, the controller26can be configured to signal the operator LED indicator driver unit108to cause the right light strip148to display the near side obstacle pattern and left light strip152to display the far side obstacle pattern.

At step S156, the controller can be configured to signal the operator LED indicator driver unit108to cause the light strips148,152to display identical obstacle warning patterns that are equal in size and at the same position on the light strips148,152.

From step S154or step S156, the controller26can be configured to move to step S158.

The controller26can be configured to signal the operator LED indicator driver unit108to adjust the size of the obstacle warning pattern as the distance to the detected object changes. At step S158, the controller26can be configured to save each measured distance to the detected object in an appropriate electronic storage device or medium such as, but not limited to, RAM or an external storage device and compare the previous distance to the current distance between the lawnmower12and the detected object. The controller26can be configured to move from step S158to step S160.

At step S160, the controller26can be configured to adjust the size of the obstacle warning pattern based on a change in the distance to the detected object. The controller26can be configured to signal the operator LED indicator driver unit108to cause the display devices94to increase the size of the obstacle warning pattern if the controller26determines that the lawnmower12is moving closer to the object and decrease the size of the obstacle pattern if the lawnmower12is moving farther from the detected object. The controller26can be configured to move from step S158to step S148and exit the obstacle display control subroutine.

As described above, an operator of the lawnmower12can manually steer the lawnmower12by manipulating the control levers28,30,176,228,230according to the first mode or the second mode of the drive-by-wire system10. The operator can cause the controller26to perform the automated turning operation by applying an input to one of the auto-turn switches84,86,196,198. The controller26can be configured to cause the display device94to present a scrolling pattern in accordance with the turning display control subroutine ofFIG.14when the operator manually turns the lawnmower12or engages the automated turn operation via one of the auto-turn switches84,86,196,198.

Referring toFIG.7, the drive by wire system10can include the right auto-turn switch84and the left auto-turn switch86that can signal the controller26to execute an automated turning operation of the lawnmower12that can steer the lawnmower through a predetermined range of motion. The auto-turn switches84,86can be mounted on the inner support172and the left light strip152. In the alternate embodiment ofFIG.8, the auto-turn switches196,198can be mounted on the handle182. The auto-turn switches196,198can have the structures and functions described with respect to the auto-turn switches84,86.

The controller26can be configured to select one of a left scrolling pattern and a right scrolling pattern when the operator manually steers the lawnmower12to the left or right, respectively, or inputs a request for an automated turn to the left or the right, respectively. During a manual turn, the controller26can use the data from the sensors32,34in the manner described above with respect to steering the lawnmower12to select the appropriate one of the left scrolling pattern and the right scrolling pattern. During the automated turning operation, the controller26can be configured to select the appropriate one of the left scrolling pattern and the right scrolling pattern based on the signals received from the switches84,86.FIG.14shows a flowchart that depicts an exemplary turning display control subroutine that can be executed by the controller26for operating the display device(s)94to express a scrolling display pattern to the operator of the lawnmower12. The scrolling warning pattern can be indicative of the turning direction (left/counterclockwise or right/clockwise) of the lawnmower's12.

The switches84,86can be in electrical communication with the controller26and can be configured to transmit a respective turn direction signal to the controller26in response to an input by the operator of the lawnmower12. Each of the switches84,86can be any appropriate switch such as but not limited to a push button, a touch sensor, or an icon on a touch screen. The switches84,86can be located at any appropriate position on the left control lever30that can permit easy access by the operator and convenient use of the left control handle30without inadvertent actuation of either of the switches84,86.FIG.7shows the switches84,86mounted in the left inner support166.FIG.8shows switches196,198mounted on the handle182of the left control lever176. The switches196,198can operate in the same manner as the switches84,86.

The first mode and the second mode of the drive-by-wire system10can include an automated turning operation that can allow the operator to instruct the controller26to drive the HSTs56L,56R so that the lawnmower12performs a predetermined change of direction. For example, in response to an operator input when the lawnmower12is traveling along a path P1in a first direction indicated by arrow A inFIG.18, the controller26can drive the HSTs56L,56R so that the lawnmower12follows either a right turn path or a left turn path and travels along a new path P2, or new path P3, that is adjacent to the previous path P1and in a direction that is opposite to the direction indicated by arrow A.

The driver unit108can be configured to cause the light strips148,152to illuminate the LEDs in a predetermined manner that can be readily recognized by the operator as an indication of the turning direction of the lawnmower12. For example, the driver unit108can be configured to signal the right light strip148in combination with the left light strip152to illuminate in a predetermined color, such as but not limited to blue, and in a predetermined pattern, such as but not limited to an increased intensity blue portion that scrolls across the light strip148,152from end to the other end over a lesser intensity blue background.

The controller26can be configured to cause illumination of the light strips148,152via commands issued to the operator LED indicator driver unit108such that a pattern that is smaller than a length of the light strip148,152starts at one end of the light strip148,152travels across the light strip148,152and ends at the other end of the light strip148,152. Alternate embodiments can include the controller26configured to signal the light strips148,152to scroll a respective pattern in a synchronized manner. The controller26can be configured to perform the automated turning operation in the first mode and the second mode. When performing the automated turn operation, the controller26can be configured to determine the speed of each of the HSTs56L,56R based on the position of the right control lever28in the first range R1and whether the controller26receives a turn direction signal from the right auto-turn switch84or the left auto-turn switch86. The controller26can be configured to determine the right HST56R is the inside motor and the left HST56L is the outside motor when the controller26receives a turn direction signal from the right auto-turn switch84and determine the left HST56L is the inside motor and the right wheel20R is the outside motor when the controller26receives a turn direction signal from the left auto-turn switch86. The controller26can be configured to determine an outside drive speed that directly corresponds to the speed signal from the right sensor32and drive the outside motor at the outside drive speed. The controller26can be configured to determine an inside drive speed that is less than the outside drive speed and drive the inside motor at the inside drive speed until the lawnmower12travels a predetermined arcuate path.

Referring toFIG.10, the wheel speed sensors88and the dynamic sensor array90can be in electrical communication with the controller26. The dynamic sensor array90can include a three-axis gyroscope and a three-axis accelerometer.

FIG.18shows a travel path of the lawnmower12when the controller26executes an automated turn to the right. The controller26can be configured to determine a current arcuate distance travelled by the lawnmower12while the controller is driving the HSTs56L,56R according to the automated turning operation of the lawnmower12. The controller26can be configured to use data from the wheel speed sensors88to determine the current arcuate distance travelled by the lawnmower12or the data from the three-axis gyroscope and/or the three-axis accelerometer to determine an angular displacement of the lawnmower12. The controller26can be configured to compare the current arcuate distance to a predetermined distance threshold (or the current angular displacement to a predetermined angular threshold). The controller26can be configured to continue a first phase of the auto-turn operation of the lawn mower12until the current arcuate distance or angular displacement is equal to the predetermined distance threshold or the predetermined angular threshold, respectively.

The predetermined threshold can correspond to the arcuate travel distance from a start point PS on the current path P1to a transition point PT on the left/right turn path. The path from the start point PS to the transition point PT can be referred to as phase1and the path from the transition point PT to the end point PE can be referred to as phase2. The current arcuate distance or the current angular displacement can be referred to as a current orientation of the lawnmower12. The current orientation can be an orientation of the lawnmower12relative to the previous path P1.

When the current orientation is equal to the predetermined threshold, the lawnmower12has completed travel along phase1. The controller26can be configured to steer the lawnmower12along phase2by driving the outside motor at a predetermined inside transition speed and the inside motor at a predetermined outside transition speed so the lawnmower12can change the arcuate path and transition from the transition point PT to the end point PE where the lawnmower12can begin traveling along the new path P2, or the new path P3. The controller26can be configured to compare the orientation of the lawnmower along phase2to a second predetermined threshold. The controller26can be configured to maintain this transitional operation until the transitional arcuate distance is equal to a second predetermined threshold. Once the controller26determines that the lawnmower12has reached the end point PE, the controller26can resume the second mode control of the HSTs56L,56R according to the drive signals and/or neutral signals received from the sensors32,34as described above with respect toFIG.6.

The controller26can be configured to abort the automated turning operation prior to its completion if the operator moves either the right control lever28or the left control lever30into a predetermined position. For example, the controller26can be configured to abort the automated turning operation if the controller26receives a signal from the right sensor32that indicates the right control lever28has been moved into the neutral position N. Additionally, or alternatively, the controller26can be configured to abort the automated turning operation if the controller26receives a signal from the left sensor34that indicates that the left control lever28has been moved into the neutral position N.

When the controller26determines that the operator is turning the lawnmower manually, or when the controller26is performing the automated turning operation of the lawnmower12, the controller26can be configured to perform the turning display control of step S120ofFIG.11. During step S120ofFIG.11, the controller26can be configured to enter the turning display control subroutine at step S162ofFIG.14. The controller26can be configured to move from step S162to step S164.

At step S164, the controller26can be configured to determine the current turning direction of the lawnmower12based on data from the sensors32,34if the operator is manually steering the lawnmower12, or from the signals from the switches84,86if the controller26is executing an automated turning operation of the lawnmower12. If the controller26determines that the lawnmower12is turning to the left (left turn condition), the controller26can move to step S166. If the controller26determines that the lawnmower12is turning to the right (right turn condition), the controller26can move to step S168.

At step S166, the controller26can be configured to send instructions to the operator LED indicator driver unit108to cause right light strip148to move the scrolling pattern from right to left across the right light strip148starting from the outer end160and ending at the inner end162and cause the left light strip152to move the scrolling pattern from the right to left across the left light strip152starting from the inner end172and ending at the outer end170. The controller26can move from step S166to step S170and end the turning display control algorithm.

At step S168, the controller26can be configured to send instructions to the operator LED indicator driver unit108to cause right light strip148to move the scrolling pattern from left to right across the right light strip148starting from the inner end162and ending at the outer end160and cause the left light strip152to move the scrolling pattern from left to right across the left light strip152starting from the outer end170and ending at the inner end172. The controller26can move from step S168to step S170and end the turning display control algorithm.

During an automated turning operation of the lawnmower12, the controller26can be configured to terminate the scrolling pattern based on the predetermined movement of either of the control levers28,30discussed above that causes the controller26to cease the automated turning operation.

Accordingly, the drive-by-wire system10can permit an operator of the lawnmower12to operate the control levers28,30in either a first mode, which can mimic a traditional operation of the control levers28,30, or a second mode, which can simplify the input demand(s) on the operator and provide an increased precision in the directional control of the lawnmower12as compared to the first mode. Further, the display system200can enhance the operator's awareness of the operational status of the lawnmower12. Further still, the drive-by-wire system10can provide one or more automated operations of the lawnmower12that can improve the performance of the lawnmower12in the second mode as compared to the first mode and provide obstacle detection and avoidance in both the first mode and the second mode.

The wheel speed sensors88can be mounted on an appropriate portion of the lawnmower12to detect rotation of the respective drive wheel20L,20R. The raw data from the wheel speed sensors88can be processed by one or both of the wheel speed sensors88or by the controller26to indicate a rotational velocity and direction of the respective drive wheels20L,20R. The wheel speed sensors88can be any type of sensor capable of providing the appropriate data.

Electrical communication lines and electrical power supply lines (not numbered) can connect the controller26to the other components and systems of the drive-by-wire system10. Electrical communication can be either one-way communication or two-way communication and can be networked or not networked. The controller26, the operator LED indicator driver unit108, the ultrasonic sensor/LiDAR processing unit110and the vision system processing unit112also can be referred to as an electronic control unit (ECU) or as a central processing unit. the controller26and the units108,110,112can include a processor and a memory storage device. The controller26and the units108,110,12can be configured with hardware and/or software to perform the task(s) described above.

While certain embodiments of the invention are described above, it should be understood that the invention can be embodied and configured in many different ways without departing from the spirit and scope of the invention.

For example, embodiments are disclosed above in the context of lawnmower12shown inFIG.1. However, embodiments are intended to include a drive-by-wire system for any type of vehicle. For example, the drive-by-wire system10can be used with a skid steer vehicle or a vehicle that is propelled by two or more tracks.

Embodiments are described above in the context of a lawnmower12that is powered by single power source54and driven by HSTs56L,56R. However, embodiments are intended to include an electric power source54that drives the blades38and a respective electric motor for each of the drive wheels20L,20R in replacement of the HSTs56L,56R.

A lawnmower12that is powered by an electric power source54can include an autonomous operation system that is configured to mow the lawn as an autonomous vehicle that does not require the presence of an operator on the lawnmower12. The autonomous operation system can include a learning mode in which the operator drives the lawnmower12around the perimeter of the work area to define the operational boundary in which the lawnmower12will operate autonomously. During the learning mode, the display system200can operated in any manner described above. The autonomous operation system can include a cutting mode in which the lawnmower12autonomously traverses the work area learned during the learning mode and mows the vegetation in the work area. The cutting mode can implement the obstacle detection and automated turning features described above. The cutting mode can operate the display system200in any manner described above.

The lawnmower12shown inFIGS.1,2,5-7,9and15-17is described as having a seat18for the operator. Alternative embodiments of the lawnmower can omit the seat18and include a platform on which the operator may stand while operating the lawnmower. The platform can be located at the rear end of the lawnmower. The size and location of the control levers28,30can be changed to accommodate the change in orientation of the operator. The power source54can be moved forward so that it is in front of the platform.

The subroutines shown inFIGS.12-14are described as being incorporated into a single algorithm ofFIG.11. However, exemplary embodiments can include a controller26that is configured to execute the operations described with respect toFIGS.11-14as separate routines and the controller26can be configured to assign a priority to each display control if more than one display control is viable during the current operating conditions for the lawnmower. For example, the controller26can be configured to prioritize the display of a tilt warning pattern over the obstacle warning pattern or the scrolling pattern.

Instead of the configuration shown inFIG.6, the controller26can be configured such that the controller26determines the forward and reverse directions from the left handle30instead of the right handle28, and determines the turning direction from the right handle28instead of the left handle30when in the second mode. Further, the drive-by-wire system10can include one or more inputs that enable the operator to selectively customize which of the control levers28,30determines the forward and reverse directions and which of the handles28,30controls the turning direction in the second mode.

Instead of mounting the mode selector36on the control panel80, exemplary embodiments can include a mode switch on one of the control levers28,30.

Instead of the control levers28,30described above, exemplary operator inputs can include a pair of joysticks, one on each side the seat18, and mounted on or adjacent to a respective fender of the lawnmower12.

Instead of mounting the automatic turn buttons84,86on the left handle30, the buttons84,86can be mounted on the control panel80.

The control system could be configured to allow automatic turning in accordance with the first mode. In this configuration, the automatic turn feature could be limited to operate when the control levers are both within a predetermined threshold of the maximum travel. The speed of the machine, and the speed of the turn, can be controlled with the aforementioned rotary knob or lever mounted to the handle.

The display device94is described above as including light strips mounted on or incorporated into the control levers. However, exemplary embodiments of the display device can include the light strips located remotely on the front of the machine, above a windscreen, inside an operator's helmet, or along the top or bottom of an operator's glasses. The LED indicator display functions could be emulated using an augmented reality display for the operator.