FIELD OF THE INVENTION

The present application generally relates to a mobility vehicle and, more particularly, to a steering assembly and a control system for a mobility vehicle such as a scooter.

BRIEF SUMMARY OF THE INVENTION

In some embodiments, a vehicle comprises: a frame having longitudinal axis; a steering assembly having a steering input and at least one wheel, the steering assembly coupled to the frame and configured to steer the vehicle based on input from the steering input; a first drive wheel and a second drive wheel; a steering position sensor configured to detect a position of the steering input and at least one of i) a rate of change of the position of the steering input and ii) a steering position time; and at least one controller configured to process a signal from the steering position sensor and, in response to the processed signal, drive the first drive wheel and the second drive wheel, the first drive wheel being driven independently of the second drive wheel.

In some embodiments, the vehicle further comprises a first motor coupled to the at least one controller and the first drive wheel and a second motor coupled to the at least one controller and the second drive wheel, wherein the first drive wheel is driven by the first motor and the second drive wheel driven by the second motor in response to one or more drive signals from the at least one controller.

In some embodiments, the first motor is configured to drive the first drive wheel in a first direction and the second motor is configured to drive the second drive wheel in a second direction opposite the first direction.

In some embodiments, the first motor receives a first drive signal of the one or more drive signals from the at least one controller to drive the first drive wheel and the second motor receives a second drive signal of the one or more drive signals from the at least one controller to drive the second drive wheel.

In some embodiments, the second drive signal has an amount of current that, when received by the second motor, causes the second motor to drive the inner drive wheel at a speed of 0 revolutions per minute.

In some embodiments, while the vehicle is turning in a left or right direction, the first drive wheel is the outer drive wheel and the second drive wheel is the inner drive wheel, the inner drive wheel being closer to a center of a turning path of the vehicle than the outer drive wheel and wherein the first motor is configured to drive the outer drive wheel in a first direction at a speed greater than 0 revolutions per minute and the second motor is configured to drive the inner drive wheel at a speed of 0 revolutions per minute.

In some embodiments, the at least one wheel includes a left front wheel and a right front wheel.

In some embodiments, a distance between the left front wheel and the right front wheel is less than a distance between the first drive wheel and the second drive wheel.

In some embodiments, the at least one controller is configured to: receive one or more signals related to the position of the steering input and at least one of i) the rate of change of position of the steering input, an ii) the steering position time; and command the first motor and the second motor to drive the first wheel and second wheel in opposite directions based upon the one or more drive signals.

In some embodiments, the steering assembly includes a steering linkage configured and dimensioned such that each of the left front wheel and the right front wheel have: a maximum inward turn angle characterized by a limit to which either the left front wheel or right front wheel can turn toward the longitudinal axis, and a maximum outward turn angle characterized by a limit to which either the left front wheel or right front wheel can turn away from the longitudinal axis, wherein when one of the left front wheel or the right front wheel is an outside wheel turned to a respective left or right maximum inward turn angle, the other of the left front wheel or right front wheel is an inside wheel turned to an intermediate maximum outward turn angle that is less than the maximum outward turn angle unless a biasing force is applied to the inside wheel to urge the inside wheel to the respective maximum outward turn angle.

In some embodiments, the biasing force is a function of a difference between a voltage in a first drive signal provided to a first motor to drive the first drive wheel and a voltage in a second drive signal provided to a second motor to drive the second drive wheel.

In some embodiments, the biasing force is applied to the inside wheel independent of the movement of the steering input.

In some embodiments, the tiller, when operated by a user, is configured to turn the inside wheel up to, without exceeding, the intermediate maximum outward turn angle.

In some embodiments, the biasing force is caused by a force exerted by the ground.

In some embodiments, the intermediate maximum outward turn angle is different from the maximum outward turn angle by approximately 10°.

In some embodiments, the at least one wheel includes a left front wheel and a right front wheel, and wherein a steering linkage is configured to engage a stop when one of the left front wheel or the right front wheel reaches a respective maximum outward turn angle to prevent said left or right front wheel from turning beyond the respective maximum outward turn angle.

In some embodiments, the steering linkage further comprises a linkage member configured to pivot in response to movement of the steering input.

In some embodiments, the linkage member includes a tie rod.

In some embodiments, the at least one wheel includes a left front wheel and a right front wheel, and wherein the steering assembly further comprises: a steering stem, a stem tab coupled to the steering stem, an axle beam pivotably mounted to the frame, the axle beam comprising a left stop and right stop, a left king pin and right king pin coupled to the axle beam, and a left tie rod and a right tie rod, each of the left and right tie rods being pivotably coupled to the stem tab and to the left king pin and right king pin respectively, wherein each of the left and right tie rods is configured to pivot in response to movement of the steering input and to engage the left or right stop respectively when one of the left front wheel or the right front wheel reaches a respective maximum outward turn angle to prevent said left or right front wheel from turning beyond the respective maximum outward turn angle.

In some embodiments, the left king pin is rotatable about a left king pin axis and the right king pin is rotatable about a right king pin axis, and wherein each of the left king pin and the right king pin is pivotably coupled to the respective left and right tie rod that translates relative to the axle beam when the left or right king pin rotates about the respective left and right king pin axis.

In some embodiments, the axle beam is further coupled to the frame by at least one suspension member configured to allow each of the left front wheel and right front wheel to translate relative to the frame.

In some embodiments, each of the left front wheel and the right front wheel is translatable relative to the frame by a value between 0.25 inches and 1 inch.

In some embodiments, the vehicle further comprises a swing arm pivotably coupled to the frame and fixed to the axle beam.

In some embodiments, the vehicle further comprises a left and a right steering arm coupled to the left and right kingpin respectively, each of the left and right steering arm being rotatable about and projecting from the left and right kingpin respectively; and a left and right wheel axle coupled to the left and right kingpin respectively, each of the left and right wheel axle being rotatable about the left and right king pin axis respectively and projecting from the left and right kingpin respectively, the left front wheel and right front wheel being rotatable about the respective left and right wheel axle, wherein each of the left and right steering arm is fixed relative to the left and right wheel axle respectively at an angle of approximately 73°.

In some embodiments, the each of the left and right king pin axes is oriented relative to the frame at a camber angle of approximately 4 degrees.

In some embodiments, the each of the left and right king pin axes is oriented relative to the frame at a caster angle of approximately 2 degrees.

In some embodiments, the maximum outward turn angle is approximately 91 degrees.

In some embodiments, the vehicle further comprises a rear wheel axis about which the first and second drive wheels rotate; a left and right front wheel axis about which the respective left and right front wheels rotate; and a left and right front wheel axis vertical projection extending through the left and right front wheel axis, the left and right front wheel axis vertical projections intersecting at a point that is forward of the rear wheel axis when one of the left or right front wheel is at the maximum outward turn angle.

In some embodiments, the left and right front wheel axis vertical projections intersect at a point that is set off from the longitudinal axis on a left side of the frame when the left front wheel is at the maximum outward turn angle.

In some embodiments, one of the axle beam or the left or the right steering arm comprises an adjustable steering stop that is fixed to the one of the axle beam or the left or the right steering arm and is configured to limit the motion of the left or the right steering arm relative to the axle beam to a first degree when the adjustable steering stop is in a first configuration and to limit the motion of the left or the right steering arm relative to the axle beam to a second degree when the adjustable steering stop is in a second configuration wherein the first degree is less than the second degree.

In some embodiments, the vehicle is further configured and dimensioned to produce the biasing force when the vehicle is operated in a forward direction.

In some embodiments, the vehicle is configured and dimensioned to reduce the biasing force in response to a reduction in a difference between relative torque applied to the first and second drive wheels, respectively.

In some embodiments, the vehicle further comprises a retractable steering stop configured to restrict pivoting movement of one of the left or right steering arms relative to the axle beam when the retractable steering stop is in an engagement ready position.

In some embodiments, the retractable steering stop is further configured to not restrict pivoting movement of one of the left or right steering arms relative to the axle beam when the steering stop is in a retracted position.

In some embodiments, the vehicle further comprises a retraction means configured to cause the retractable steering stop to toggle from the engagement ready position to a retracted position based upon at least one of: a user command, vehicle speed, a position of the steering input, a duration in the position of the steering input and the rate of change of position of steering input.

In some embodiments, the steering position sensor is configured to detect the position of the steering input and the rate of change of the position of the steering input.

In some embodiments, a mobility scooter comprises: a frame having longitudinal axis; a steering assembly, coupled to the frame, having a left front wheel and a right front wheel on either side of the longitudinal axis, each of the left front wheel and the right front wheel coupled to the vehicle via a steering linkage configured to steer the mobility scooter based on input from a user; a first drive wheel driven by a first motor about a drive wheel axis and a second drive wheel driven by a second motor about the drive wheel axis, the drive wheel axis having a center point equally spaced between the first drive wheel and the second drive wheel, an inside drive wheel being one of the first drive wheel and the second drive wheel closest to a center of a turning path of the mobility scooter, wherein an axis of rotation of the mobility scooter during a turn intersects the drive wheel axis between the center point and a centerline of the inside drive wheel.

In some embodiments, the left front wheel, the right front wheel, the first drive wheel, and the second drive wheel are each laterally spaced from the longitudinal axis by an approximately equal distance.

In some embodiments, the steering linkage is configured and dimensioned such that each of the left front wheel and the right front wheel have: a maximum inward turn angle characterized by a limit to which the front of either the left front wheel or the right front wheel can turn toward the longitudinal axis, and a maximum outward turn angle characterized by a limit to which the front of either the left front wheel or right front wheel can turn away from the longitudinal axis, wherein when one of the left front wheel and the right front wheel is an outside wheel turned to a respective left or right maximum inward turn angle, the other of the left front wheel and the right front wheel is an inside wheel turned to an intermediate maximum outward turn angle that is less than the maximum outward angle until a biasing force is applied to the inside wheel to urge the inside wheel to the respective maximum outward turn angle.

In some embodiments, the mobility scooter is configured to turn about the axis of rotation when the inside wheel is turned to the maximum outward turn angle and to turn about a different axis of rotation when the inside wheel is turned to the intermediate maximum outward turn angle.

In some embodiments, the mobility scooter comprises a controller configured to simultaneously drive the first drive wheel and the second drive wheel in opposite directions when the inside drive wheel is in the maximum outward angle.

In some embodiments, the controller powers each of the first drive wheel and the second drive wheel at power levels of approximately the same absolute value and in different directions when the inside drive wheel is in the maximum outward angle.

In some embodiments, the first drive wheel operates at a different angular velocity that the second drive wheel when the power levels are of approximately the same absolute value.

In some embodiments, the steering assembly includes a steering linkage pivotable at each end of the steering linkage.

In some embodiments, the controller powers each of the first drive wheel and the second drive wheel at power levels of approximately the same absolute value and opposite polarities to apply torque in opposite directions to each of the first and second drive wheels, when the inside drive wheel is in the maximum outward angle.

In some embodiments, a vehicle, comprises a frame having longitudinal axis; a steering assembly having a steering input and a single directional control wheel, the steering assembly coupled to the frame and configured to steer the vehicle based on input from a steering input; a first drive wheel and a second drive wheel; a steering position sensor configured to detect steering input including a position of the steering input and at least one of i) a rate of change of position of steering input and ii) steering position time; and at least one controller configured to process a signal from the steering position sensor and, in response to the processed signal, drive the first drive wheel and the second drive wheel, the first drive wheel being driven independent of the second drive wheel.

In some embodiments, a vehicle, comprises a steering assembly configured to steer the vehicle based on an input from a steering input; a first drive wheel driven by a first motor and a second drive wheel driven by a second motor; a throttle configured to receive a speed input from a user; at least one steering sensor configured to detect steering input including at least one of i) input associated with a position of the steering input and ii) input associated with a rate of change of position of the steering input; and at least one controller communicatively coupled to the first motor, the second motor, and the steering sensor, the at least one controller configured to: receive one or more steering indicators associated with the at least one steering sensor; determine whether the steering indicator meets major turn entering criteria based on the position of the steering input and at least one of i) the rate of change of the position of steering input and ii) a steering position time lapse; in response to a determination that the steering indicator meets major turn entering criteria: operate the first motor and the second motor in major turn mode, including the at least one controller being configured to: provide a first drive signal to the first motor, the first drive signal configured to cause the first motor to drive the first drive wheel in a forward direction at a first speed that is less than a commanded speed indicated by the throttle, and provide a second drive signal to the second motor, the second drive signal configured to cause the second motor to drive the second drive wheel in a reverse direction at a second speed that is less than a commanded speed indicated by the throttle.

In some embodiments, the at least one controller being configured to determine whether the steering indicator meets the major turn entering criteria includes the at least one controller being configured to determine that the position of the steering input is in a major turn position and determine that the rate of change of the position of the steering input exceeds a predetermined steering rate of change threshold.

In some embodiments, the at least one controller being configured to determine whether the steering indicator meets the major turn entering criteria includes, the at least one controller being configured to: determine that the position of the steering input is in a major turn position, and determine that steering position of the steering input has transitioned from an intermediate turn position to the major turn position in an amount of time that is less than a predetermined steering rotation timing threshold.

In some embodiments, the at least one controller being configured to determine that the steering indicator meets the major turn entering criteria includes, the at least one controller being configured to: determine that the position of the steering input is in a major turn position, after a determination that the position of the steering input is in the major turn position, determine that the rate of change of the position of the steering input is less than a predetermined steering rate of change threshold, and after a determination that the rate of change of the position of the steering input is less than a predetermined steering rate of change threshold, confirm that the position of the steering input is in the major turn position.

In some embodiments, the at least one controller being configured to determine that the steering indicator meets the major turn entering criteria includes, the at least one controller being configured to: determine that the position of the steering input is in a major turn position, after a determination that the position of the steering input is in the major turn position, determine that steering position of the steering input has transitioned from an intermediate turn position to the major turn position in an amount of time that is greater than a predetermined steering rotation timing threshold, and after determining that steering position of the steering input has transitioned from an intermediate turn position to the major turn position in an amount of time that is greater than a predetermined steering rotation timing threshold, confirm that the position of the steering input is in the major turn position.

In some embodiments, the predetermined steering rotation timing threshold is approximately 250 ms.

In some embodiments, the at least one steering sensor includes: an intermediate turn position sensor to detect that the steering input is in an intermediate turn position, and a major turn position sensor to detect that the steering input is in a major turn position, wherein the rate of change of the position of the steering input is based on a time to transition from an intermediate turn position, as detected by the intermediate turn position sensor, to a major turn position, as detected by the major turn position sensor.

In some embodiments, the at least one steering sensor includes an accelerometer to detect movement of the steering input for determining the rate of change of the position of the steering input.

In some embodiments, the steering sensor includes a force sensor to detect a force applied to the steering input for determining when a steering input has transitioned to, or transitioned from, a major turn position.

In some embodiments, the at least one controller being configured to determine that the steering indicator meets the major turn entering criteria includes the at least one controller being configured to determine that the steering input is in a major turn position and the steering position time lapse is greater than a predetermined major turn position timing threshold.

In some embodiments, the predetermined major turn position timing threshold is approximately 250 ms.

In some embodiments, the vehicle comprises a vehicle turn rate sensor that detects a turn rate of the vehicle, and wherein the at least one controller is further configured to: while the first motor and the second motor are operating in major turn mode, determine whether the turn rate of the vehicle, as detected by the vehicle turn rate sensor, is less than a predetermined turn rate threshold, determine whether a turn rate commanded by the throttle is greater than a commanded turn rate threshold, and in response to a determination that the turn rate of the vehicle is less than a predetermined turn rate threshold and that the turn rate indicated by the throttle is greater than the commanded turn rate threshold: provide a third drive signal to the first motor, the third drive signal configured to cause the first motor to drive the first drive wheel in a forward direction at a third speed that is greater than the first speed, and provide a fourth drive signal to the second motor, the second drive signal configured to cause the second motor to drive the second drive wheel in a reverse direction at a fourth speed that is greater than the second speed.

In some embodiments, the at least one controller is further configured to: while the first motor and the second motor are operating in major turn mode, determine whether the turn rate of the vehicle, as detected by the vehicle turn rate sensor, is greater than a predetermined turn rate threshold, in response to a determination that the turn rate of the vehicle is greater than a predetermined turn rate threshold: provide a fifth drive signal to the first motor, the fifth drive signal configured to cause the first motor to drive the first drive wheel in a forward direction at a fifth speed that is less than the first speed, and provide a sixth drive signal to the second motor, the sixth drive signal configured to cause the second motor to drive the second drive wheel in a reverse direction at a sixth speed that is less than the second speed.

In some embodiments, the vehicle turn rate sensor is an inertial measurement sensor.

In some embodiments, the vehicle turn rate sensor is an accelerometer.

In some embodiments, the at least one controller is further configured to: while the motors are operating in major turn mode and in response to a determination that the steering input has transitioned from a major turn position to an intermediate turn position: provide a seventh drive signal to the second motor, the seventh drive signal configured to cause the second motor to rotate the second drive wheel in the forward direction.

In some embodiments, the at least one controller is further configured to: while the first motor and the second motor are operating in major turn mode and in response to a determination that the steering input has transitioned from a major turn position to a minor turn position: provide an eighth drive signal to the second motor, the eighth drive signal configured to cause the second motor to rotate the second drive wheel in the forward direction at a commanded speed indicated by the throttle and continue providing the first drive signal to the first motor during a first time period, and after the first time period, provide a ninth motor drive signal to the first motor, the ninth motor drive signal configured to cause the first motor to rotate the first drive wheel in the forward direction at a commanded speed indicated by the throttle.

In some embodiments, the first time period is between 20 ms and 1000 ms.

In some embodiments, the at least one controller is further configured to: in response to a determination that the steering indicator does not meet major turn entering criteria: operate the first motor and the second motor in standard driving mode, including: providing a tenth drive signal to the first motor, the tenth drive signal configured to cause the first motor to drive the first drive wheel in the forward direction at a commanded speed indicated by the throttle and providing an eleventh drive signal to the second motor, the eleventh drive signal configured to cause the second motor to drive the second drive wheel in the forward direction at a commanded speed indicated by the throttle.

In some embodiments, the vehicle comprises a tilt sensor configured to detect tilt angle of the vehicle, and wherein the at least one controller being configured to determine whether the steering indicator meets the major turn entering criteria includes the at least one controller being configured to determine whether the tilt angle of the vehicle, as detected by the tilt sensor, along the lateral axis or longitudinal axis, is less than a predetermined tilt angle threshold.

In some embodiments, the throttle is configured to receive a reverse speed input to direct the vehicle to move in a reverse direction, wherein the at least one controller is configured to: in response to a determination that the steering position meets a major turn entering criteria, and in response to a determination that the throttle receives a reverse input: provide a twelfth drive signal to the first motor, the twelfth drive signal configured to cause the first motor to drive the first drive wheel in a direction opposite a direction indicated by the first drive signal, at a twelfth speed that is less than the first speed, and provide a thirteenth drive signal to the second motor, the thirteenth drive signal configured to cause the second motor to drive the second drive wheel in a direction opposite a direction indicated by the second drive signal, at a thirteenth speed that is less than the second speed.

In some embodiments, the twelfth drive signal is configured to cause the first motor to drive the first drive wheel at approximately 50 percent of a power of the first motor as caused by the first drive signal, wherein the thirteenth drive signal is configured to cause the second motor to drive the second drive wheel at approximately 50 percent of a power of the second motor as caused by the second drive signal.

In some embodiments, the throttle is configured to receive a reverse speed input to direct the vehicle to move in a reverse direction, wherein the at least one controller is configured to: in response to the throttle receiving a reverse input, determine that the steering indicator does not meet major turn entering criteria.

In some embodiments, the first speed and the second speed are approximately 30 percent of a commanded speed indicated by the throttle while the at least one controller is operating in an indoor mode and wherein the first speed and the second speed are approximately 60 percent of a commanded speed indicated by the throttle while the at least one controller is operating in an outdoor mode.

In some embodiments, the vehicle comprises an environmental mode selection input selectable by a user and configured to cause the at least one controller to operate in the indoor mode or in the outdoor mode.

In some embodiments, the environmental mode selection input is on the steering input.

In some embodiments, the environmental mode selection input is a switch on the steering input.

In some embodiments, the vehicle comprises an operator weight sensor that detects a weight of an operator of the vehicle and wherein the at least one controller is further configured to: while the first motor and the second motor are operating in major turn mode, determine that the weight of the operator, detected by the operator weight sensor, exceeds a predetermined operator weight threshold, and in response to a determination that the weight of the operator exceeds a predetermined operator weight threshold: provide a fourteenth drive signal to the first motor, the fourteenth drive signal configured to cause the first motor to drive the first drive wheel in the forward direction at a fourteenth speed that is greater than the first speed and provide a fifteenth drive signal to the second motor, the fifteenth drive signal configured to cause the second motor to drive the second drive wheel in the reverse direction at a fifteenth speed that is greater than the second speed.

In some embodiments, the predetermined operator weight threshold is 250 lbs.

In some embodiments, the fourteenth drive signal and fifteenth drive signal cause the first motor and the second motor to drive the first drive wheel and the second drive wheel, respectively, using approximately twice the power as compared to the first drive signal and the second drive signal, respectively.

In some embodiments, the first drive signal is configured to cause the first motor to drive the first drive wheel at approximately 30 percent of a maximum power of the first motor, wherein the second drive signal is configured to cause the second motor to drive the second drive wheel at approximately 15 percent of a maximum power of the second motor.

In some embodiments, the fourteenth drive signal is configured to cause the first motor to drive the first drive wheel at approximately 60 percent of a maximum power of the first motor, wherein the fifteenth drive signal is configured to cause the second motor to drive the second drive wheel at approximately 30 percent of a maximum power of the second motor.

In some embodiments, the major turn exiting criteria includes a criterion that is met when a time period that the vehicle operates in a major turn mode exceeds a major turn mode time limit threshold.

In some embodiments, the major turn mode time limit threshold is a function of a weight of an operator of the vehicle.

In some embodiments, the major turn mode time limit threshold when the weight of the operator of the vehicle is less than an operator weight threshold is approximately half an amount of time as the major turn mode time limit threshold when the weight of the operator of the vehicle is greater than an operator weight threshold.

In some embodiments, the operator weight threshold is 250 lbs.

In some embodiments, the major turn mode time limit threshold is between 7 and 10 seconds.

In some embodiments, the vehicle comprises a steering assembly configured to steer the vehicle based on a steering input from a user; a left drive wheel and a right drive wheel; a left motor coupled to the left drive wheel and configured to drive the left drive wheel; a right motor coupled to the right drive wheel and configured to drive the right drive wheel; a throttle configured to receive a speed input from the user; at least one full left turn position sensor configured to detect the steering assembly transitioning into and out of a full left turn; at least one full right turn position sensor configured to detect the steering assembly transitioning into and out of a full right turn; a controller communicatively coupled to the first motor, the second motor, the throttle, the at least one left turn position sensor, and the at least right turn position sensor, the controller configured to: receive a full left turn signal from the left turn position sensor, in response to receiving the full left turn signal from the left turn position sensor: provide a first drive signal to the right motor, the first drive signal configured to cause the right motor to drive the right drive wheel in a forward direction at a first speed that is less than a commanded speed indicated by the throttle, and provide a second drive signal to the left motor, the second drive signal configured to cause the left motor to drive the left drive wheel in a reverse direction at a second speed that is less than a commanded speed indicated by the throttle; receive a full right turn signal from the right turn position sensor, in response to receiving the full right turn signal from the right turn position sensor: provide a third drive signal to the left motor, the third drive signal configured to cause the left motor to drive the left drive wheel in a forward direction at a third speed that is less than a commanded speed indicated by the throttle, and provide a fourth drive signal to the right motor, the fourth drive signal configured to cause the right motor to drive the right drive wheel in a reverse direction at a fourth speed that is less than a commanded speed indicated by a throttle.

In some embodiments, the vehicle comprises at least one intermediate left turn position sensor configured to detect the steering assembly transitioning into and out of an intermediate left turn; at least one intermediate right turn position sensor configured to detect the steering assembly transitioning into and out of an intermediate right turn; wherein the controller is configured to: receive at least one of: an intermediate left turn signal from the intermediate left turn position sensor and an intermediate right turn signal from the intermediate right turn position sensor, in response to receiving at least one of: an intermediate left turn signal and the intermediate right turn signal: provide a fifth drive signal to the left motor, the fifth drive signal configured to cause the left motor to drive the left drive wheel in a forward direction at a commanded speed indicated by the throttle, and provide a sixth drive signal to the right motor, the sixth drive signal configured to cause the right motor to drive the right drive wheel in a forward direction at a fourth speed that is less than a commanded speed indicated by the throttle.

In some embodiments, a vehicle comprises a steering assembly configured to steer the vehicle; a first drive wheel and a second drive wheel configured to drive the vehicle; a first motor coupled to the first drive wheel and configured to drive the first wheel; a second motor coupled to the second drive wheel and configured to drive the second wheel; a throttle configured to control the first motor and the second motor; a steering position sensor configured to detect a steering position of the steering assembly; a throttle input sensor configured to detect a throttle input of the throttle; one or more controllers communicatively coupled to the first motor, the second motor, the throttle input sensor and the steering position sensor, the one or more controllers being configured to: determine that the steering position and the throttle input meets a major turn criteria and as a result, cause the first motor to rotate in a reverse direction at a first speed and cause the second motor to rotate in a forward direction at a second speed, wherein the first speed and the second speed fall below a speed threshold; determine that the steering position and the throttle input meets a major turn exiting criteria and as a result, cause the first motor to rotate in the forward direction and cause the second motor to rotate in the forward direction at one or more speeds based on the steering position, the steering rotation speed and the throttle input.

In some embodiments, the major turn exiting criteria includes a slow transition intermediate turn criterion, and wherein the one or more controllers are further configured to: determine that the steering position and the throttle input meets slow transition intermediate turn criterion and as a result, cause the first motor to rotate in the forward direction at a third speed and cause the second motor to rotate in the first direction at a fourth speed, wherein the third speed and the fourth speed fall below a speed threshold.

In some embodiments, the slow transition intermediate turn criterion is met when the steering position of the steering assembly transitions from a major turn position to an intermediate turn position in an amount of time that exceeds a steering rotation timing threshold and the throttle input exceeds a throttle input threshold.

In some embodiments, the steering rotation timing threshold is approximately 250 ms.

In some embodiments, the major turn exiting criteria includes a fast transition intermediate turn criterion and wherein the one or more controllers are further configured to: determine that the steering position and the throttle input meets that the fast transition intermediate turn criterion and as a result: cause the first motor to rotate in the forward direction at a third speed and cause the second motor to rotate in the forward direction at a fourth speed during a first time period, and cause the first motor to rotate in the forward direction at a fifth speed and cause the second motor to rotate in the forward direction at a sixth speed during a second time period, wherein the third speed, the fifth speed, and the sixth speed exceed the speed threshold, wherein the fourth speed falls below the speed threshold, and wherein the first time period occurs before the second time period.

In some embodiments, the fast transition intermediate turn criterion is met when the steering position of the steering assembly transitions from a major turn position to an intermediate turn position in an amount of time that falls below a steering rotation timing threshold and the throttle input exceeds a throttle input threshold.

In some embodiments, the major turn exiting criteria includes a fast transition minor turn criterion, and wherein the one or more controllers are further configured to: determine that the steering position and the throttle input meets the fast transition minor turn criterion and as a result, cause the first motor to rotate in the forward direction at a third speed and cause the second motor to rotate in the forward direction at a fourth speed, wherein the third speed and the fourth speed exceed the speed threshold.

In some embodiments, the fast transition minor turn criterion is met when the steering position of the steering assembly transitions from a major turn position, through an intermediate turn position, to a minor steering position in an amount of time that falls below a steering rotation timing threshold and the throttle input exceeds a throttle input threshold.

In some embodiments, the one or more controllers are further configured to: before the determination that the vehicle meets the major turn criteria, determine that the steering position of the steering assembly transitions from an intermediate turn position to a major turn position in an amount of time that exceeds a steering rotation timing threshold and the throttle input exceeds a throttle input threshold and as a result: cause the first motor to rotate in the reverse direction at a third speed and cause the second motor to rotate in the forward direction at a fourth speed, wherein the third speed and the fourth speed fall below the speed threshold.

In some embodiments, the one or more controllers are further configured to: before the determination that the vehicle meets the major turn criteria, determine that the steering position of the steering assembly transitions from an intermediate turn position to a major turn position in an amount of time that falls below a steering rotation timing threshold and the throttle input exceeds a throttle input threshold and as a result: cause the first motor to rotate in the reverse direction at a third speed and cause the second motor to rotate in the forward direction at a fourth speed during a first time period, wherein the third speed and the fourth speed exceed the speed threshold and cause the first motor to rotate in the reverse direction at a fifth speed and cause the second motor to rotate in the forward direction at a sixth speed during a second time period, wherein the fifth speed and the sixth speed fall below the speed threshold, and wherein the second time period occurs after the first time period.

In some embodiments, the one or more controllers are further configured to: determine that the steering position meets standard drive criteria and as a result: cause the first motor to rotate in the forward direction at a third speed and cause the second motor to rotate in the forward direction at a fourth speed, the third speed and the fourth speed being based on the throttle input.

In some embodiments, the vehicle comprises a tilt sensor that detects rotational tilt angle of the vehicle, wherein the major turn criteria includes a rotational tilt criterion that is met when the rotational tilt angle of the vehicle falls below a rotational tilt angle threshold.

In some embodiments, the vehicle comprises a first directional control wheel coupled to the steering assembly via a first axle; and a second directional control wheel coupled to the steering assembly via a second axle, the first directional control wheel and the second directional control wheel being configured to reorient in response to movement of the steering assembly, wherein the first axle is independent of the second axle.

In some embodiments, the first axle pivots about a different axis than the second axle.

In some embodiments, only one directional control wheel is coupled to the steering assembly, the directional control wheel being configured to reorient in response to movement of the steering assembly.

