Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62K—CYCLES; CYCLE FRAMES; CYCLE STEERING DEVICES; RIDER-OPERATED TERMINAL CONTROLS SPECIALLY ADAPTED FOR CYCLES; CYCLE AXLE SUSPENSIONS; CYCLE SIDECARS, FORECARS, OR THE LIKE
  • B62K21/00—Steering devices
  • B62K21/08—Steering dampers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62J—CYCLE SADDLES OR SEATS; AUXILIARY DEVICES OR ACCESSORIES SPECIALLY ADAPTED TO CYCLES AND NOT OTHERWISE PROVIDED FOR, e.g. ARTICLE CARRIERS OR CYCLE PROTECTORS
  • B62J45/00—Electrical equipment arrangements specially adapted for use as accessories on cycles, not otherwise provided for
  • B62J45/40—Sensor arrangements; Mounting thereof
  • B62J45/41—Sensor arrangements; Mounting thereof characterised by the type of sensor
  • B62J45/411—Torque sensors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62J—CYCLE SADDLES OR SEATS; AUXILIARY DEVICES OR ACCESSORIES SPECIALLY ADAPTED TO CYCLES AND NOT OTHERWISE PROVIDED FOR, e.g. ARTICLE CARRIERS OR CYCLE PROTECTORS
  • B62J45/00—Electrical equipment arrangements specially adapted for use as accessories on cycles, not otherwise provided for
  • B62J45/40—Sensor arrangements; Mounting thereof
  • B62J45/41—Sensor arrangements; Mounting thereof characterised by the type of sensor
  • B62J45/412—Speed sensors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62J—CYCLE SADDLES OR SEATS; AUXILIARY DEVICES OR ACCESSORIES SPECIALLY ADAPTED TO CYCLES AND NOT OTHERWISE PROVIDED FOR, e.g. ARTICLE CARRIERS OR CYCLE PROTECTORS
  • B62J45/00—Electrical equipment arrangements specially adapted for use as accessories on cycles, not otherwise provided for
  • B62J45/40—Sensor arrangements; Mounting thereof
  • B62J45/41—Sensor arrangements; Mounting thereof characterised by the type of sensor
  • B62J45/415—Inclination sensors
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62K—CYCLES; CYCLE FRAMES; CYCLE STEERING DEVICES; RIDER-OPERATED TERMINAL CONTROLS SPECIALLY ADAPTED FOR CYCLES; CYCLE AXLE SUSPENSIONS; CYCLE SIDECARS, FORECARS, OR THE LIKE
  • B62K21/00—Steering devices
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B62—LAND VEHICLES FOR TRAVELLING OTHERWISE THAN ON RAILS
  • B62K—CYCLES; CYCLE FRAMES; CYCLE STEERING DEVICES; RIDER-OPERATED TERMINAL CONTROLS SPECIALLY ADAPTED FOR CYCLES; CYCLE AXLE SUSPENSIONS; CYCLE SIDECARS, FORECARS, OR THE LIKE
  • B62K2202/00—Motorised scooters

Definitions

• the present subject matter relates to a saddle type vehicle, which requires balancing, and more particularly to a balancing system for the saddle type vehicle.
• the present day four-wheeled vehicles can perform one autonomous task at a time.
• these vehicles mostly incorporate autonomous safety-oriented features, such as automatic lane keeping or adaptive cruise control.
• Some other advanced four-wheeled vehicles can perform two autonomous tasks at a time, for example, steering as well as performing lane-keeping, or auto-braking and adaptive cruise control.
• the four-wheeled vehicles are implementing these electric powers assisted systems (EPAS), and electronic stability programs (ESP).
• EPAS electric powers assisted systems
• ESP electronic stability programs
• the two-or three-wheeled vehicles which are typically saddle-ride type vehicles.
• the saddle-ride type vehicles are unstable and have the tendency to roll over or capsize towards one lateral side.
• the vehicles including two-and three-wheeled vehicles are steered by operating a handle bar in order to operate one or more front wheels.
• the rider has to exert high steering forces in order to maneuver the vehicle.
• the inertia of a steering system is higher causing fatigue to the rider to balance the vehicle, let alone performing maneuvering.
• FIG. 1 illustrates a left-side view of an exemplary vehicle, in accordance with an embodiment of the present subject matter.
• FIG. 2 depicts a steering support system supported by a frame assembly of a vehicle, in accordance with an embodiment of the present subject matter.
• FIG. 3 (a) illustrates a flow chart illustrating a method of operation of a balancing system, in accordance with an embodiment of the present subject matter.
• FIG. 3 (b) illustrates a flow chart depicting a method of operation of a balancing system, in accordance with an embodiment of the present subject matter.
• FIG. 4 illustrates a method of controlling the balancing system by a current control (current-controller operation), in accordance with an embodiment of the present subject matter.
• FIG. 5 (a) illustrates a balancing system, in accordance with a second embodiment of the present subject matter.
• FIG. 5 (b) illustrates a method of functioning of a balancing system comprising a balancing-control unit, in accordance with an embodiment of the present invention, in the form of a flowchart.
• the rider has to continuously and consciously perform maneuvering operation to achieve balance and to avoid fall. That is because, unlike four-wheelers, the saddle ride vehicles are influenced by external parameters also, such as irregular road surface or change in friction of terrain due to rains or the like. These external parameters may cause the vehicle highly unstable or imbalanced, which generally leads to fall or accidents. It is even more challenging for a novice rider to achieve balance as there is no knowledge of force required or steering angle required for balancing. Unless for an experienced rider, the amount of steering torque and steering angle to be applied cannot be gauged by the novice rider. Even for the experienced rider such continuous and conscious maneuvering creates fatigue especially in traffic conditions. Thus, the rider of the vehicle, finds it difficult to balance the vehicle while operating at low-speeds.
• a torque on the wheels is modified by providing a positive or negative acceleration. Even though this may provide balance, such a technique is not preferred as it causes a change in acceleration or deceleration of the vehicle, which may result in accidents. Without the intention or knowledge of the driver, the vehicle may be accelerated or decelerated to attain stability whereby the vehicle may run into a vehicle in front or get hit by a vehicle in the behind (during sudden deceleration).
• the present subject matter provides a balancing system and a method thereof, that addresses the aforementioned and other problems of the prior art.
• the method of operation of a balancing system for balancing a vehicle comprises the steps of receiving information from a plurality of sensors of the vehicle.
• the plurality of sensors primarily includes an angle sensor.
• the plurality of sensors provides information corresponding to dynamic conditions of the vehicle to a balancing-control unit.
• a balancing steering angle is calculated based on information received for the plurality of sensors by the balancing-control unit.
• An actuator unit is connected to a steering system towards achieving the balancing steering angle to maneuver the steering system of the vehicle. This applies the balancing steering angle to achieve balancing and then the balancing steering angle is compared with an actual steering angle applied by the rider.
• Comparing or identifying a difference between the balancing steering angle enables the balancing-control unit to identify a rider intention. Accordingly, the system identifies an updated vehicle running condition based on difference between the actual steering angle and the steering angle. The system then updates the balancing steering angle based on the updated vehicle running condition and accordingly the actuator unit is driven to maneuver the steering system thereby achieving stability.
• the method and the system provide the balancing steering angle, at the same time acknowledges the rider intention, thereby performing the balancing operation first and then performing the rider intended maneuvering operation.
• the method of operation of the balancing system comprises of actuating of the actuator unit by applying an actuator angle, which is same as the balancing steering angle, and an actuator torque towards achieving the balancing steering angle to maneuver the steering system of the vehicle.
• the system considers the inertia of the steering system and accordingly provides the actuator torque for easing the steering operation for the rider.
• the steering system comprises a steering shaft rotatably journaled about a frame assembly (a head tube of the frame assembly, as per one implementation).
• the actuating of the actuator unit performs rotation of the steering shaft by one of a direct engagement or through a torque enhancer unit.
• the torque enhancer unit is configured to provide a gear ratio to cater to the steering operation of the steering system.
• the method further comprises of determining a mean of the actual steering angle over a pre-determined time.
• the mean of the actual steering angle taken over the pre-determined time eliminates any error value in the actual steering (for example, error values may occur due to unintentional maneuvers or fluctuation due to road surfaces or other parameters).
• the balancing-control unit identifies the change in actual steering angle with respect to the balancing steering angle over the pre -determined time period.
• the method comprises the step of estimating a difference between the mean and the actual steering angle, and the estimated difference is compared with a balancing steering angle in order to obtain the updated vehicle condition.
• the updated vehicle condition will be a steady maneuver condition when the difference (difference between the mean and the balancing-steering angle) being less than a threshold angle.
• the system identifies that there is no input from the rider side and the vehicle is also in the steady maneuvering condition.
• the updated vehicle condition will be a transient maneuvering condition when the difference (difference between the mean and the balancing-steering angle) being greater than a threshold angle.
• the balancing system performs balancing first by modifying the input to the actuator unit and then enables the rider to perform the transient operation.
• a mathematical time differential (rate of change) between the actual steering angle and the balancing steering angle is considered.
• the updated vehicle running condition is identified as a steady maneuvering condition when the differential and the difference (the mean and the balancing-steering angle) both are less than a corresponding threshold.
• the differential provides a rate of change of the actual steering angle whereby the balancing-control unit performs a proportionate control.
• the updated vehicle running condition is identified as a transient maneuvering condition when any of the differential (between the actual steering angle and the balancing steering angle), and the difference (the mean and the balancing-steering angle) are greater than a corresponding threshold.
• the balancing system identifies an abnormality and performs balancing.
• the updating of balancing steering angle is performed for a next instance. The updated balancing steering angle is kept same as the balancing steering angle, estimated earlier for the next instance, when the updated vehicle running condition is a steady maneuvering condition.
• updating of the balancing steering angle is done for a next instance.
• the updated balancing steering angle is a time integration of the balancing steering angle, estimated earlier, and a time differential between the actual steering angle and the balancing steering angle. Such a correction is performed when the updated vehicle running condition is a transient maneuvering condition.
• the balancing steering angle and the updated balancing steering angle are applied to the actuator unit by one of a current- controlled or a voltage-controlled operation.
• a method of current control for operation of the balancing system comprises the steps of receiving information from a plurality of sensors, calculating a balancing steering angle, actuating an actuator unit towards achieving the balancing steering angle, comparing the balancing steering angle with an actual steering angle applied by the nder. Further, calculating a difference between the actual steering angle and the balancing steering angle. Then identifying an updated vehicle running condition based on the above difference. Accordingly, updating the balancing steering angle based on the updated vehicle running condition and driving the actuator unit to maneuver the steering system by applying a controlling current.
• the balancing system compares the balancing steering angle with an actual steering angle applied by the rider thereby identifying an error value (error value is equal to a difference, as per one implementation).
• the method of current control for operation of the balancing system the error value is compared with an upper threshold value.
• the balancing-control unit performs an immediate correction when the error value is greater than the upper threshold value by applying a controlling current. This also implies that the rider is providing an input, which has to counteracted and then the rider intended maneuvering is performed.
• a controlling current is obtained by an integration of an estimated current, based on the balancing steering angle, with a balancing current.
• the balancing current being estimated by the balancing-control unit, which corresponds to the error value.
• the error value (between the actual steering angle and the balancing steering angle) is compared with a lower threshold value. If the error value is between the upper threshold and a lower threshold, then the balancing-control unit performs a correction by applying a controlling current.
• the controlling current when the error value is between the upper threshold and the lower threshold value, is a difference between an estimated current, obtained based on the balancing steering angle, and a balancing current, corresponding to the error value.
• the balancing current is either positive or negative depending on a rider intention identified from the earlier stage.
• the method of operation of a balancing system for balancing a vehicle comprises of receiving information from a plurality of sensors.
• the plurality of sensors primarily including a steering angle sensor and a steering torque sensor.
• calculating a balancing steering angle and a balancing steering torque Actuating an actuator unit towards achieving the balancing steering angle and the balancing steering torque.
• An updated vehicle running condition is identified based on difference between the actual steering angle and the balancing steering angle, and difference between the actual steering torque and the balancing steering torque.
• the balancing steering angle and the balancing steering torque are updated and accordingly the actuator unit is driven to maneuver the steering system.
• a difference between the balancing steering torque and the actual steering torque is calculated thereby obtaining an error value.
• the error value is compared with a threshold value to understand the rider intention.
• the present invention provides improved riding experience to experience as well as to novice riders as critical balancing function is taken care by the balancing system.
• the riders can comfortably ride in slow moving conditions like heavy traffic etc.
• the balancing system may be implemented in any two-wheeled vehicle or a three-wheeled vehicle. However, for the purpose of explanation and by no limitation, the balancing system, and corresponding additional advantages and features are described through the following embodiments. Arrows wherever provided on top right comer of the figure represent direction with respect to vehicle. Arrow F represents forward direction, arrow R represents rearward direction, arrow UW represents upward direction and arrow DW represents downward direction.
• Fig. 1 depicts a left side view of an exemplary vehicle 100, in accordance with an embodiment of the present subject matter.
• the vehicle 100 includes a frame assembly 105 (shown schematically) comprising a head tube 106, and a main frame.
• the main frame comprises a main tube 107 extending rearwardly downward from the head tube 106, and one or more rear tubes 110 extending inclinedly rearward from a rear portion of the main tube 107.
• the frame member 105 defines a step-through portion 151, which is used by rider to rest his/her feet or to load luggage thereat.
• a main tube may be adapted to extend rearward from the head tube 106 and subsequently downward defining a space below the main tube, for supporting a power unit.
• a first wheel 101 and a second wheel 102 are rotatably supported by a front suspension system 131 and a rear suspension system 134, respectively.
• the second wheel 102 may be additionally supported by a swingarm (not shown).
• a power unit 135 is swingably connected to the frame member 105 and is disposed substantially below a seat assembly 155 and rearward to the step-through portion 151.
• the power unit 135 includes a transmission system (not shown) for transferring power to the second wheel 102.
• the transmission system may include a continuously variable transmission, an automatic manual transmission, a belt/chain drive.
• the power unit 135 is an internal combustion engine.
• the power unit 135 is an electric prime mover.
• the power unit is fixedly mounted to the frame assembly 105 of the vehicle 100.
• the first wheel 101 is pivotally supported by the frame assembly 105 and a handle bar assembly 150 is functionally connected to the first wheel 101 for maneuvering and steering the vehicle 100.
• the handle bar assembly 150 may support an instrument cluster, vehicle controls including throttle, clutch, or electrical switches.
• a seat assembly 155 is supported by the frame assembly 105 and the rider can operate the vehicle 100 in a seated position on the seat assembly 155.
• the vehicle 100 includes the step-through portion 151 formed between the handle bar assembly 150 and the seat assembly 155.
• the vehicle 100 is provided with plurality of panels 170A, 170B, 170C mounted to the frame assembly 105 and covering the frame assembly 105 and/or parts of the vehicle 100.
• the plurality of panels includes a front panel 170A and a leg-shield 170B covering a head tube 106 of the frame assembly 105 in forward and rearward direction, respectively.
• a rear panel assembly 170C is disposed substantially below the seat assembly 155.
• the rear panel assembly 170C substantially covers a utility box (not shown) disposed below the seat assembly 155 and also, covering at least a portion of the power unit 135.
• the vehicle 100 is provided with a balancing system 200 (shown in Fig 2 (a)), which is discussed in following description.
• Fig. 2 illustrates a schematic side view of a balancing system 200 supported on a frame assembly 105 of a vehicle 100, in accordance with an embodiment of the present subject matter.
• the vehicle 100 comprises a steering system 120, which includes a steering shaft 212.
• the steering shaft 212 is rotatably journaled about the head tube 106 (the frame assembly 105).
• the steering shaft 212 comprises a lower end to which a lower bridge 215 is connected to.
• the lower bridge 215 is configured to support the front suspension system 131.
• the front suspension system 131 rotatably supports the first wheel 131.
• the steering shaft 212 is rotatable about a steering axis S-S’.
• the vehicle 100 comprises a positive trail, as the steering axis S-S’ extends ahead of a point of contact 190 of the first wheel 101 to road surface. Further, the present invention enables retaining the trail, say a positive trail, and does not require any change in trail during balancing operation of the vehicle.
• the balancing system 200 of the vehicle 100 comprises of an actuator unit 205, which may directly operate the steering system 120.
• a torque enhancer unit 210 is functionally connected to the actuator unit 205.
• the actuator unit 205 is fixedly mounted to the frame assembly 105.
• an extension member is fixed to the frame assembly 105 and the actuator unit 205 is supported on the extension member.
• the steering axis S-S’ is parallel to the actuator axis A-A’ .
• the torque enhancer unit 210 is configured to provide driving force from the actuator unit to the steering shaft 212.
• an existing configuration of head tube 106 is retained in the vehicle, without the need for changing a front portion (say head tube portion) of the frame assembly 105.
• the head tube portion is modified to accommodate the actuator unit and allied sub-systems.
• the balancing system 200 of the vehicle 100 comprises a plurality of sensors that provide a dynamic operating conditions related information of the vehicle 100. Furthermore, a balancing-control unit 235 is mounted on the vehicle 100. In one embodiment, a steering angle sensor 250, which forms part of the plurality of sensors is mounted between an actuator unit shaft (not shown) of the actuator unit 205 and the torque enhancer unit 210. The present subject matter is capable of performing the balancing operation by receiving steering angle information of the steering system 120 from the steering angle sensor 250.
• the steering angle sensor 250 which is a critical sensor, is either directly or indirectly connected to the steering shaft 212. In case of an indirect connection, the steering angle sensor 250 is connected through an intermediate gear or an intermediate gear assembly of the torque enhancer unit 210 or the like.
• the steering angle sensor 250 is compactly accommodated on the vehicle without disturbing the function of the steering shaft 212, the actuator unit 205 and the handlebar assembly 150.
• the steering angle sensor 250 is configured to provide data/ information related to steering angle of the steering shaft 212.
• a top portion of the steering shaft 212 is functionally connected to a handlebar assembly 150 through a connecting means 216.
• the plurality of sensors includes, and not limited to, a speed sensor (not shown), a global positioning system (GPS) unit 230, an inertia measurement unit (IMU) 240 supported by the frame assembly 105.
• one or more sensor 230, 240 of the plurality of sensors are disposed at the posterior region of the vehicle and substantially in close vicinity of the balancing control unit 235 to enable a compact and secure layout of the vehicle.
• the plurality of sensors is communicatively coupled to the balancing-control unit 235 in order to provide various dynamic operating conditions of the vehicle 100.
• a balancing-control unit 235 is supported by the rear tubes 110 of the frame assembly 105. In another embodiment, the balancing-control unit 235 may be disposed at any other portion of the frame assembly 105, subject to layout of the vehicle 100.
• the balancing -control unit 235 is communicatively coupled to the actuator unit 205 in order to activate/deactivate or control operation of the actuator unit 205.
• the balancing -control unit 235 is configured to balance the vehicle 100 by controlling the operation of the actuator unit 205 and correspondingly control an angle of the steering shaft 212. The method of operation of the balancing system is explained through the following illustrations.
• Fig. 3 illustrates a flow chart depicting a method of operation of the balancing system, in accordance with a first embodiment of the present subject matter.
• the method considers inputs from the plurality of sensors including the steering angle sensor 250.
• the balancing-control unit 235 receives inputs from the plurality of sensors to obtain information related to dynamic condition of the vehicle 100 (herein reference is made to Figs. 1 & 2 for system level components).
• a speed v is sensed from speed sensor.
• the speed v can be obtained from the GPS unit 230.
• the speed v is measured using a Hall sensor or an encoder, which is locally provided in the vehicle 100.
• ) is sensed from the IMU 240.
• the roll angle is estimated from a roll angular velocity (a roll angle displacement may directly be measured using IMU 240).
• the balancing -control unit 235 is configured to balance the vehicle 100. Further, the vehicle 100 is provided with low speed/high speed stability, a steering assist (to reduce steering effort for the rider) and other dynamics improvements.
• the balancing-control unit 235 receives the dynamic condition of the vehicle 100.
• a balancing steering angle A s is calculated by the balancing system 200 by receiving information related to steering angle from one or more sensor.
• the balancing steering angle As is estimated using various parameters of the dynamic condition of the vehicle 100.
• a look-up table may be provided with various steering angles corresponding to various dynamic running conditions of the vehicle.
• the actuator unit 205 is applied with a current or voltage to perform the steering control operation.
• the current to be applied is calibrated for various riding and road conditions and stored in the look-up table for the balancing -control unit 235.
• the balancing -control unit 235 is configured to apply the balancing steering angle As to the actuator unit 205.
• the actuator unit 205 operates towards achieving the balancing steering angle A s and accordingly, a steering torque may be applied by the actuator unit 205, at step S320.
• an actual steering angle As’ of the steering system 120 is measured using the steering angle sensor 250 and is fed to the balancingcontrol unit 235.
• a difference (error value) between the actual steering angle As’ and the balancing steering angle As is analysed by the balancing control unit 235 to determine a rider intention and a riding condition of the vehicle 100, at step S330.
• a rider intention is determined from a deviation of the actual steering angle from the balancing steering angle. For example, the rider intention to maneuver in a direction away from the balancing steering angle is recorded by the balancingcontrol unit 235.
• the balancing -control unit 235 performs balancing operation and operates the steering system 120 in a direction of the rider intention recorded earlier.
• a mean of the actual steering angle A s is measured over a pre -determined time duration. Further, a difference between the mean, and the balancing steering angle As’ is calculated by the balancing-control unit 235 i.e. mean [As (t- n : t)] - As (t) ⁇ for ease, referred to as difference ⁇ . Where n defines time duration for which the value is measured. The means helps in identifying a quantity of the maneuvering operation that is happening. Similarly, a time differential/differentiation value between actual steering angle As’ and the balancing steering angle A s is also measured i.e. diff [As’(t)-As(t)] ⁇ for ease, referred to as differential angle ⁇ .
• a rate of change of the state of steering system is monitored by the balancing-control unit 235.
• the difference and the differential are measured to identify a riding condition of the vehicle 100.
• the difference and differential are compared (to check if they are less than) with a threshold angle Ath and a differential threshold angle Adth.
• the comparison equations are shown below:
• the balancing-control unit 235 based on the comparison, at step S335, if the outcome of the equations (1) & (2) is ‘Yes’, then at step S340, the balancing-control unit 235 identifies that the vehicle is in a steady maneuvering condition.
• the steady maneuvering condition is identified, as there is minimal to negligible variation on the left side portion of the equations (1) and (2) or the difference and differential is less the corresponding thresholds. If the difference or differential from equations (1) and (2) is more than the threshold, then the balancing -control unit 235 has to take a corrective action.
• the mean i.e.
• step S335 if the output of the equation (1) or (2) is a ‘No’, which is, the difference or the differential has crossed a threshold valves Ath or Adth, then the balancing -control unit 235 identifies the motion of the vehicle 100 as a transient maneuvering condition. Upon detecting the transient maneuvering condition, the balancing -control unit 235 corrects the balancing steering angle, for the next instance, by adding the differential between the actual steering angle and the balancing steering angle to the balancing steering angle, estimated earlier to detection of updated vehicle condition, for the next instance, i.e.
• the balancing steering angle for the next instance is depicted as A s (t+1).
• the balancing steering angle A s (t+1) gets updated by adding the differential value between the measured steering angle A s ’(t) and the balancing steering angle As(t+1) estimated earlier. This difference is added to the balancing steering angle for the next instance.
• This updated balancing steering angle for next instance is fed to the actuator unit 205, at step S360.
• the vehicle is balanced by the balancing system 200 by applying required angle and torque to the steering system 120 through the actuator unit 205, at step S365 by applying the balancing steering angle / torque to the actuator at step 360.
• the balancing-control unit 235 estimates a balancing steering torque T based on inputs received from the plurality of sensors. Then determines a balancing steering torque T and triggers the actuator unit 205 with input corresponding to the balancing steering torque T thereby balancing the vehicle.
• the handlebar assembly 150 (rider) and the actuator unit 205 are capable of providing input parallelly to the steering shaft 212 to maneuver the vehicle 100.
• the balancing -control unit 235 initially, operates the handlebar assembly 150 in a direction opposite to the direction of rotation of the rider (rider intention) for balancing the vehicle 100.
• the equation (3) includes a gain factor Gl, which is multiplied with the differential [Diff (As’(t) - As (t))] between the balancing steering angle As’ and the balancing steering angle As.
• the gain factors Gl is being a value between 0 and 1.
• the gain factor is chosen is chosen based on rate at which the control action has to be taken. For an immediate control, the gam factor is chosen to be maximum.
• the balancing system 200 is activated at predetermined conditions of the vehicle 100. For example, when the rider is operating the vehicle 100 at low-speeds (say at a speed less than 5 kilometers per hour, as per one embodiment), the balancing system 200 is activated. In order to balance the vehicle 100 at such low speeds, the rider usually provides a balancing input to the vehicle 100 by operating the handlebar assembly 150 of the steering system. However, the input provided by the rider may not be sufficient, or may not be in the right direction or with the required rate. The balancing system 200 gets actuated and it applies a partial or complete balancing angle and torque to the steering shaft 212. The steering shaft 212 receives input from the handlebar assembly 150 and from the actuator unit 205.
• the actuator unit 205 provides a steering/ torque assist towards performing an intended steering maneuver.
• the balancing-control unit 235 is configured to estimate a torque to be applied using data from one or more sensors of the plurality of the sensors that include the inertia measurement unit 240, a speed sensor (not shown), a global positioning sensor unit 230 etc.
• the balancing system 200 predominantly uses data from the steering angle sensor 250.
• the balancing system 200 performs a current control operation to provide the required angle and torque.
• Fig. 3 (b) illustrates a flow chart depicting the method of operation of the system, in accordance with an embodiment of the present subject matter.
• the method of operation of a balancing system 200 for balancing a vehicle 100 is elaborated in the following steps.
• the balancing control unit 235 receives information from a plurality of sensors 230, 240, 250, including a steering angle sensor 250, which provides information corresponding to dynamic conditions of the vehicle 100.
• the balancing -control unit 235 calculates a balancing steering angle A s based on information received for the plurality of sensors 230, 240, 250 [in the aforementioned step].
• the balancing control unit 235 actuates an actuator unit 205 towards achieving the balancing steering angle As by performing steering angle control for maneuvering the steering system 120 of the vehicle 100.
• the balancing control unit 235 compares the balancing steering angle A s with an actual steering angle As’ of the steering system 120.
• the balancing control unit 235 identifies an updated vehicle running condition based on difference between the actual steering angle As’ and the balancing steering angle As.
• the balancing control unit 235 updates the balancing steering angle As based on the updated vehicle running condition and accordingly driving the actuator unit 205 to maneuver the steering system 120.
• Fig. 4 illustrates a method of controlling the balancing system by a current control (current-controller operation), in accordance with an embodiment of the present subject matter.
• the method considers inputs from the plurality of sensors including the steering angle sensor 250.
• the balancing-control unit 235 receives inputs from one or more sensors to obtain information related to dynamic condition of the vehicle. For example, a speed v is sensed from speed sensor. In one implementation, the speed v can be obtained from the GPS unit 230. In yet another implementation, the speed v is measured using a Hall sensor or an encoder, which is locally provided in the vehicle 100.
• ) is sensed from the IMU 240. In one implementation, the roll angle is estimated from a roll angular velocity (a roll angle displacement may directly be measured using IMU 240).
• the balancing -control unit 235 receives the dynamic condition of the vehicle 100 as a state parameter.
• a balancing steering angle A s is calculated by the balancing system 200.
• the balancing -control unit 235 is configured to control the actuator unit 205 by sending signals (current control signal) corresponding to the balancing steering angle As to the actuator unit 205.
• the actuator unit 205 performs steering operation towards achieving the balancing steering angle As.
• an actual steering angle As’ of the steering system 120 is measured using the steering angle sensor 250 and is fed to the balancing -control unit 235.
• a difference (error value) between the actual steering angle As’ and the balancing steering angle A s is assessed by the balancing control unit 235 to determine a rider intention and a riding condition of the vehicle 100, at step S430.
• is compared with an upper threshold value Em u. If the error value is greater than the upper threshold value, if [
• the balancing-control unit 235 identifies the rider intention or the direction of rotation being performed by the rider.
• the balancing-control unit 235 provides a controlling current I’, which is, an estimated current I (based on balancing steering angle As) added / integrated with a balancing current II.
• the negative or positive value of the balancing current I’ depends on rider intention identified from the earlier stage.
• the balancing current would be applied in positive or negative form [sign (+, -)] to the actuator unit 205, which is an electric motor in one embodiment, for directional control of the steering system 120 at step S445.
• the balancing is dependent on rider intention identified from the comparison of the balancing steering angle A s with the actual steering angle As’.
• the vehicle 100 achieves a balanced condition and the balancing-control unit 235 enables the rotation of the steering system 120 as per rider intention and subsequently continues to monitor dynamic state parameter of the vehicle at step S405.
• step S450 the error value is compared with a lower threshold Eth_L. If the error value is less than the lower threshold Eth_L, in that case, the controller current I’ is same as the estimated current I. If at step S450, the error value is greater than the lower threshold, then at step S460, the balancing current I’ is achieved by subtracting a balancing current II from the estimated current I and corresponding input is provided to the actuator at step S465 followed by continues to monitor dynamic state parameter of the vehicle at step S405.
• the balancingcontrol unit 235 will achieve the balancing steering angle As and then follow the rider instruction with respect to desired direction of rotation.
• a range between the upper threshold Em u and the lower threshold Em_u is decided based on the rider feel and vehicle tuning. For example, the range can be varied based on speed of operation, terrain or road surface, and vehicle configuration.
• the directional control is performed for balancing and subsequently, the rider intention is performed.
• the current control operation is performed to achieve, the New balancing steering angle of step S345/step S355 of Fig. 3.
• Fig. 5 (a) illustrates a balancing system 500, in accordance with a second embodiment of the present subject matter.
• Fig. 5 (b) illustrates a method of functioning of a balancing system 500 comprising a balancing-control unit 535, in accordance with an embodiment of the present invention, in the form of a flowchart 600.
• the balancing-control unit 535 receives data from a GPS unit or vehicle speed sensor 565 and calculates a vehicle speed/velocity V.
• a balancing -control unit 535 receives dynamic data from one or more sensor of the vehicle including a steering angle sensor 550, a torque sensor 560, a roll angle/roll rate sensor 540 like IMU and the speed sensor 545.
• a gear ratio related information is used a dynamic data in case of gear box being used a torque converter between a steering system 120 and an actuator unit 505.
• the balancing-control unit 535 calculates a balancing steering angle As and step 615, a balancing steering torque T is estimated for balancing the vehicle 100.
• a required balancing steering torque is estimated and is applied.
• the balancing-control unit 235 receives estimates an inertia from a differential between the actual steering angle and the steering input provided to the actuator unit 205.
• the balancing-control unit 535 applies, the estimated balancing steering torque T to the actuator unit 505 corresponding to the balancing steering angle.
• the actuator unit 505 starts performing the maneuvering of the steering system 120 to the achieve the balancing steering angle As for balancing the vehicle 100.
• the steering system 120 is controlled by the actuator unit 505.
• the balancing-control unit 535 at steps S630 & S635, measures an actual steering torque T’ an actual steering angle As’ from the data from the steering angle sensor and the torque sensor.
• step S640 a difference between the balancing steering torque T and the actual steering torque T’ is estimated.
• step S655 an error value/the difference between the actual steering torque T’ and the balancing steering torque T is measure and is compared with a threshold value Tth.
• step S650 an error value/the difference between the actual steering angle As’ and the balancing steering angle A s is measured and compared with a threshold value Ath.
• step S650 if a magnitude (absolute value) of error value in the angle is less than the threshold values Ath, then the vehicle is determined to be in a balanced state, as per step S655. No further, control is required for the current instance.
• step S665 if the magnitude of error value in torque is less than the threshold values Tth, the balancing -control unit 535 concludes that there is input from rider and there is no change in riding condition and road condition.
• step S665 if the error value is greater than the threshold value Tth, then at step S670, the balancing-control unit 535 detects that there is a rider input with a deviation from the balancing steering torque T.
• the balancingcontrol unit 535 recalibrates the balancing steering angle A s and the balancing steering torque at steps S610 and S615.
• the torque and angle control provide improved balancing control by understanding rider intention.
• the balancing -control unit 535 performs a current control or a voltage control to operate and control the actuator unit 505 and thereby controlling the steering system 120 for stability. Since, at step S665 or at step S650, once the balancingcontrol unit 535 identifies the vehicle is not balance, the balancing-control unit receives the dynamic information of the vehicle (thereby updating the vehicle running condition) and accordingly calculating and inputting an updated balancing steering angle As.
• step-through portion 155 seat assembly 170A front panel
• leg shield 170C rear panel assembly 190 point of contact 200 balancing system 205/505 actuator unit 210 torque enhancing unit 212 steering shaft

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Steering Devices For Bicycles And Motorcycles (AREA)
• Steering Control In Accordance With Driving Conditions (AREA)
• Power Steering Mechanism (AREA)
• Testing Of Balance (AREA)

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• 2021
  • 2021-12-02 EP EP21831373.2A patent/EP4255797A2/de active Pending
  • 2021-12-02 JP JP2023533965A patent/JP7698720B2/ja active Active
  • 2021-12-02 WO PCT/IN2021/051132 patent/WO2022118342A2/en not_active Ceased

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