Electric vehicle, control device, drive control method, and program

Abstract

An electric vehicle according to the present invention comprises a wheel that is provided to a vehicle body, a motor that makes the wheel rotate, a grip unit that detects the operation force with which a user is gripping, and a drive control unit that performs assist control that corresponds to at least the operation force at the grip unit by controlling drive of the motor. When power from a battery is lost, the drive control unit can perform the assist control by controlling drive of the motor using regenerative power generated from the motor by rotation of the wheel. The drive control unit can also perform emergency brake control for performing brake control regardless of the operation force at the grip unit. When power from the battery is lost, the drive control unit can perform the emergency brake control by controlling drive of the motor using regenerative power.

Description

Electric vehicle, control device, drive control method, and program

[0001] The present invention relates to an electric vehicle, a control device, a drive control method, and a program. This application claims priority from Japanese Patent Application No. 2024-228329 filed in Japan on December 25, 2024, the content of which is incorporated herein by reference.

[0002] Conventionally, electric vehicles such as wheelchairs and carts that generate auxiliary power by an electric motor have been known. For example, a wheelchair that generates auxiliary power by an electric motor powered by supply power from a detachably attached battery is known (see, for example, Patent 1 below).

[0003] Japanese Unexamined Patent Application Publication No. 2019-141255

[0004] However, in the prior art, when an abnormality occurs in the power supply from the battery, there is a risk of problems in the safe use by the user.

[0005] One object of the present invention is to provide a technology that allows a user to safely use the vehicle even when an abnormality occurs in the power supply from the battery.

[0006] An electric vehicle according to one aspect of the present invention includes wheels provided on a vehicle body, a motor that rotates the wheels by power supplied from a battery, a grip portion that detects an operating force grasped by a user, and a drive control portion that controls the drive of the motor to execute assist control according to at least the operating force of the grip portion. The drive control portion can control the drive of the motor by regenerative power generated from the motor when the wheels rotate in the case of power loss of the battery and execute the assist control.

[0007] With the above configuration, the user can safely use the vehicle even when an abnormality occurs in the power supply from the battery. Even when there is a power loss of the battery, assist control can be executed as in the case before the power loss. Therefore, for example, even if there is a power loss of the battery in a dangerous place where it is difficult to move without assist control, it is possible to move by assist control, improving safety.

[0008] In the above configuration, the drive control unit is capable of performing abnormal brake control, which controls the brakes regardless of the operating force of the grip unit, and the drive control unit may also be capable of performing the abnormal brake control by controlling the drive of the motor with the regenerative power in the event of a power loss of the battery.

[0009] With the above configuration, users can safely operate the vehicle even if there is a problem with the power supply from the battery. For example, if there is a loss of battery power, abnormal braking control can be executed. Therefore, even if there is a loss of battery power in a dangerous place such as a slope, the vehicle will stop due to the abnormal braking control, thus improving safety.

[0010] In the above configuration, if the battery loses power unintended by the user, the drive control unit may control the motor drive using the regenerative power and perform the abnormal brake control.

[0011] With the above configuration, users can safely use the system even if there is a problem with the power supply from the battery. For example, safety is further improved because abnormal braking control is performed appropriately (i.e., with increased precision) depending on the situation.

[0012] An electric vehicle according to another aspect of the present invention includes wheels provided on the vehicle body, a motor that rotates the wheels using power supplied from a battery, a grip portion that detects the operating force applied by the user, a drive control portion that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip portion, a power detection portion that detects whether power from the battery is supplied to the motor or the drive control portion, and a power switching portion that, when the power detection portion detects that power is not being supplied, performs control to supply regenerative power generated from the motor by the rotation of the wheels to the drive control portion.

[0013] With the above configuration, users can safely use the device even if there is a problem with the power supply from the battery. Even if the battery loses power, the assist control can be performed as before the power loss. For example, even if the battery loses power in a dangerous place where it would be difficult to move without assist control, movement will still be possible with assist control, thus improving safety.

[0014] In the above configuration, the drive control unit is capable of performing abnormal brake control, which controls the brakes regardless of the operating force of the grip unit, and the drive control unit, which is supplied with regenerative power by the control of the power switching unit, may perform the abnormal brake control.

[0015] With the above configuration, users can safely operate the vehicle even if there is a problem with the power supply from the battery. For example, if there is a loss of battery power, abnormal braking control can be executed. Therefore, even if there is a loss of battery power in a dangerous place such as a slope, the vehicle will stop due to the abnormal braking control, thus improving safety.

[0016] In the above configuration, the drive control unit is capable of performing brake control according to the operating force of the grip unit, and includes a switch unit capable of receiving an ON operation to switch from an OFF state in which assist control according to the operating force of the grip unit and brake control according to the operating force of the grip unit are not performed, to an ON state in which assist control according to the operating force of the grip unit and brake control according to the operating force of the grip unit are performed, and an OFF operation to switch from the ON state to the OFF state. The drive control unit may, when the supply of regenerative power is started, not perform the abnormal brake control if the switch unit had received the OFF operation before the supply of regenerative power was started, and may perform the abnormal brake control when the supply of regenerative power is started, if the switch unit had not received the OFF operation before the supply of regenerative power was started.

[0017] In the above configuration, the system includes a flag control unit that controls a predetermined flag stored in a non-volatile memory unit, wherein the flag control unit clears the predetermined flag when the switch unit receives the ON operation, and sets the predetermined flag when the switch unit receives the OFF operation, and the drive control unit may not perform the abnormal brake control when the predetermined flag is set at the start of the regenerative power supply, and may perform the abnormal brake control when the predetermined flag is not set at the start of the regenerative power supply.

[0018] In the above configuration, the drive control unit may, when executing the abnormal brake control, stop executing the abnormal brake control in response to the switch unit receiving the off operation.

[0019] In the above configuration, the drive control unit may, while executing the abnormal brake control, discontinue the execution of the abnormal brake control if the direction of movement of the vehicle body coincides with the operating direction of the grip portion and the operating force of the grip portion is greater than or equal to a predetermined threshold.

[0020] In the above configuration, the drive control unit may resume the execution of the abnormal brake control after ceasing its execution, if predetermined conditions are met.

[0021] Another aspect of the present invention relates to a control device for controlling an electric vehicle comprising wheels provided on a vehicle body, a motor that rotates the wheels using power supplied from a battery, and a grip portion that detects the operating force applied by a user, the control device comprising a drive control portion that controls the drive of the motor and performs assist control corresponding to at least the operating force applied by the grip portion, wherein, in the event of a power loss from the battery, the drive control portion can control the drive of the motor using regenerative power generated from the motor by the rotation of the wheels, thereby enabling the execution of the assist control.

[0022] With the above configuration, users can safely use the device even if there is a problem with the power supply from the battery.

[0023] Another aspect of the present invention relates to a drive control method for controlling an electric vehicle comprising wheels provided on a vehicle body, a motor that rotates the wheels using power supplied from a battery, and a grip portion that detects the operating force applied by a user. The control device performs a drive control step that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip portion. In the drive control step, if there is a loss of power from the battery, the drive of the motor is controlled by regenerative power generated from the motor as the wheels rotate, thereby enabling the execution of the assist control.

[0024] With the above configuration, users can safely use the device even if there is a problem with the power supply from the battery.

[0025] Another aspect of the present invention relates to a program that causes a computer to function as a control device for controlling an electric vehicle comprising wheels provided on a vehicle body, a motor that rotates the wheels using power supplied from a battery, and a grip portion that detects the operating force applied by a user, wherein the computer functions as a drive control means that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip portion, and the drive control means is capable of performing the assist control by controlling the drive of the motor with regenerative power generated from the motor by the rotation of the wheels in the event of a power loss from the battery.

[0026] With the above configuration, users can safely use the device even if there is a problem with the power supply from the battery.

[0027] According to the present invention, users can safely use the device even if there is an abnormality in the power supply from the battery.

[0028] A diagram showing an example of an electric vehicle. A diagram showing an example of an electric vehicle. A diagram showing an example of the configuration of the electric vehicle 100 including the control unit 200. An explanatory diagram describing the operating modes controlled by the control unit 200. A flowchart showing an example of operation when transitioning from power OFF mode M1 to other operating modes. A flowchart showing an example of operation when transitioning from power ON mode M2 ​​to other operating modes. A flowchart showing an example of operation when transitioning from no-power mode M3 to other operating modes. A flowchart showing an example of operation when transitioning from abnormal brake mode M4 to other operating modes. A diagram showing an example of another configuration of the electric vehicle 100 including the control unit 200. A flowchart showing another example of operation when transitioning from abnormal brake mode M4 to other operating modes.

[0029] First, embodiments of the present invention will be described based on the drawings.

[0030] (Example of an electric vehicle) Figures 1A and 1B show an example of an electric vehicle. The electric vehicle 100 shown in Figures 1A and 1B is an electric wheelchair. As shown in Figures 1A and 1B, the electric vehicle 100 comprises a seat system 110, a drive system 120, and an operating system 130.

[0031] In Figures 1A and 1B, when the electric vehicle 100 moves in the F direction, it is referred to as "forward." When the electric vehicle 100 moves in the B direction, it is referred to as "reverse." Furthermore, when the electric vehicle 100 moves in the T direction (left and right direction), it is referred to as "turning."

[0032] (Seat system 110) The seat system 110 includes a cushion seat 111 and a footrest 112. The cushion seat 111 is the seat on which the passenger sits. Specifically, the cushion seat 111 includes a seat cushion and a back cushion. The footrest 112 is a footrest on which the passenger rests their feet.

[0033] (Drive System 120) The drive system 120 includes a power switch 121, a battery 122, a drive motor 123, a drive wheel 124, a caster 125, a tipping lever 126, and a band brake 127. The power switch 121 receives the on / off switch for controls that assist the operator through the rotation (drive) of the drive motor 123 (forward assist control (described later), reverse brake control (described later), reverse assist control (described later), forward brake control (described later)). The battery 122 is a storage battery that charges the electricity that will be the power source for the electric vehicle 100. The battery 122 is housed in a battery cover 122a.

[0034] The drive motor 123 includes a right drive motor 123R and a left drive motor 123L. The right drive motor 123R uses electricity from the battery 122 to drive and rotate the right drive wheel 124R. The left drive motor 123L uses electricity from the battery 122 to drive and rotate the left drive wheel 124L.

[0035] The drive wheels 124 include a right drive wheel 124R located on the right side in the direction of travel and a left drive wheel 124L located on the left side in the direction of travel. The drive wheels 124 are the rear wheels of the electric vehicle 100 and rotate in conjunction with the rotation of the drive motor 123. The casters 125 include a right caster 125R located on the right side in the direction of travel and a left caster 125L located on the left side in the direction of travel. The casters 125 are the front wheels of the electric vehicle 100 and are swivel parts with built-in bearings. The casters 125 change the direction of travel of the electric vehicle 100 in accordance with the operation of the operator (caregiver).

[0036] The tipping lever 126 is a lever that the operator places their foot on and steps down to raise the caster 125 when encountering a step or other obstacle. That is, when the tipping lever 126 is stepped down, the caster 125 rises, and the electric vehicle 100 can overcome the step. The band brake 127 generates a braking force to stop the drive wheel 124 in response to the operation of the brake lever 132. The band brake 127 comprises a rotating brake drum and a friction material that tightens the brake drum from the outside. Braking force is obtained by the friction material tightening the brake drum.

[0037] (Operating System 130) The operating system 130 includes an operating grip 131 and a brake lever 132. The operating grip 131 includes a right operating grip 131R and a left operating grip 131L. The right operating grip 131R is an operating handle that the operator grasps with their right hand. The left operating grip 131L is an operating handle that the operator grasps with their left hand. The right operating grip 131R and the left operating grip 131L have a push-pull mechanism. The brake lever 132 is a lever that, when gripped by the operator, generates braking by the band brake 127.

[0038] (Forward assist control, reverse brake control, reverse assist control, forward brake control) When the power switch 121 is turned ON, the system enters a state where operator-assistant control is performed. Specifically, when the power switch 121 is ON, forward assist control, reverse brake control, reverse assist, or forward brake control is performed by the drive motor 123 in response to the operation (push / pull) of the operating grip 131. When the power switch 121 is turned OFF, the system enters a state where operator-assistant control is not performed (free state). Specifically, when the power switch 121 is OFF, neither forward assist control, reverse brake control, reverse assist control, nor forward brake control is performed even if the operating grip 131 is operated. Note that the assist control (forward assist control, reverse assist control) is a control that applies torque to the drive wheels 124 in the same direction of rotation as the rotating drive wheels 124. In other words, it is a control that promotes the movement of the moving electric vehicle 100. Brake control (reverse brake control, forward brake control, abnormal brake (described later)) is a control that applies torque to the rotating drive wheels 124 in a direction different from the direction of rotation of the rotating drive wheels 124. In other words, it is a control that suppresses the movement of the moving electric vehicle 100.

[0039] Forward assist control is an assist control that assists in the forward direction by pushing the operating grip 131 when moving forward on an uphill or flat road. The assist provided by forward assist control is sometimes referred to as forward assist. An uphill slope is a slope where the front side of the electric vehicle 100 (direction F in Figure 1) is higher than the rear side (direction B in Figure 1). Reverse brake control is a brake control that suppresses acceleration due to gravity in the reverse direction and allows for slow reverse movement when reversing on an uphill slope by pushing the operating grip 131 (being pushed in by gravity). The brake provided by reverse brake control is sometimes referred to as reverse brake. Reverse assist control is an assist control that assists in the reverse direction by pulling the operating grip 131 (being pulled by gravity) when reversing on a downhill slope. The assist provided by reverse assist control is sometimes referred to as reverse assist. A downhill slope is a slope where the front side of the electric vehicle 100 is lower than the rear side. Forward braking control is a braking system that, when moving forward on a downhill slope, pulls the control grip 131 (due to gravity), suppressing acceleration due to gravity in the forward direction and allowing for slow forward movement. The braking performed by forward braking control is sometimes referred to as forward braking.

[0040] In some cases, the brakes driven by the drive motor 123 and the brakes driven by the band brake 127 are distinguished and referred to as the drive brakes, while the brakes driven by the drive motor 123 are referred to as the special brakes. In addition to brakes operated by the operator (pushing and pulling the operating grip 131) (reverse brake, forward brake), there are also abnormal brakes that are not operated by the operator (also called emergency brakes, described later). The control of abnormal brakes is called abnormal brake control. An example of a drive brake is a regenerative brake.

[0041] (Other examples of the electric vehicle 100) The electric vehicle 100 is not limited to an electric wheelchair. The electric vehicle 100 may be any hand-pushed vehicle that is operated by an operator, such as a transport cart, a shopping cart or walker for the elderly, a child's cart, or a stroller. Furthermore, the electric vehicle 100 according to this embodiment is a four-wheeled vehicle equipped with drive wheels 124 (right drive wheel 124R and left drive wheel 124L) and casters 125 (right caster 125R and left caster 125L). However, the electric vehicle 100 is not limited to four wheels. The electric vehicle 100 only needs to be equipped with drive wheels 124 (two drive wheels) on at least the left and right sides, and may be, for example, two-wheeled or three-wheeled, or even five-wheeled or more-wheeled.

[0042] (Example of a configuration including the control unit 200) This figure shows an example of a configuration including the control unit 200 that the electric vehicle 100 is equipped with. As shown in Figure 2, the electric vehicle 100 includes a power switch 121, a battery 122, a drive motor 123, a grip sensor 140, a control unit 200, and a storage unit 300. In Figure 2 (and similarly in Figure 8), although not shown, the electric vehicle 100 is equipped with a power detection unit. In Figure 2 (and similarly in Figure 8), although not shown, the electric vehicle 100 may also be equipped with a power switching unit.

[0043] The power switch 121, battery 122, and drive motor 123 have already been described. The power detection unit (not shown) and power switching unit (not shown) will be described later. The grip sensor 140 includes a right grip sensor 140R and a left grip sensor 140L. The right grip sensor 140R is a sensor that detects the operating force applied to the right operating grip 131R (the direction of push and pull operation of the right operating grip 131R (the direction of displacement of the right operating grip 131R), and the amount of push and pull operation of the right operating grip 131R (the amount of displacement of the right operating grip 131R)). The left grip sensor 140L is a sensor that detects the operating force applied to the left operating grip 131L (the direction of push and pull operation of the left operating grip 131L (the direction of displacement of the left operating grip 131L), and the amount of push and pull operation of the left operating grip 131L (the amount of displacement of the left operating grip 131L)).

[0044] The control unit 200 is realized by a hardware processor such as a CPU (Central Processing Unit) executing a program (software). Some or all of these components may be realized by hardware (including a circuit unit; circuitry) such as an LSI (Large Scale Integration), an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a GPU (Graphics Processing Unit), or may be realized by the cooperation of software and hardware. The program may be stored in advance in a storage device (a storage device having a non-transitory storage medium) such as an HDD (Hard Disk Drive) or a flash memory, or may be stored in a removable storage medium (non-transitory storage medium) such as a USB (Universal Serial Bus) flash memory, an SSD (Solid State Drive), a DVD, or a CD-ROM, and may be installed by mounting the storage medium on a drive device. Further, the program may be stored in an external device (e.g., a server) and appropriately updated by connecting to a network.

[0045] The storage unit 300 is a non-volatile storage member. For example, the storage unit 300 may be a readable and writable semiconductor memory. The control unit 200 and the storage unit 300 are integrally configured as a microcontroller (Micro Controller Unit). The dashed frame A indicates the microcontroller. Note that the storage unit 300 may be configured separately from the control unit 200 as a memory chip (memory chip).

[0046] The battery 122 supplies power to the microcontroller A (control unit 200 and storage unit 300) and the drive motor 123. The microcontroller A is supplied with power from the battery 122. The microcontroller A may also be supplied with power from the drive motor 123. The drive motor 123 is supplied with power from the battery 122. Also, the drive motor 123 can supply power to the microcontroller A. That is, the drive motor 123, which is an engine, operates with the power supplied from the battery 122, but also operates as a generator that generates regenerative power due to the rotation of the drive wheels 124. For example, when there is no power supply from the battery 122 to the microcontroller A and the microcontroller A is not activated, the drive wheels 124 rotate, the drive motor 123 rotates in response to the rotation of the drive wheels 124, a regenerative power is generated in the drive motor 123, and the generated regenerative power starts to supply power to the microcontroller A, and the microcontroller A is activated. That is, when there is a power loss in the battery 122, the power supply is switched to the power supply by regenerative power.

[0047] Whether there is a power supply from the battery 122 (power supply to the drive motor 123 and the microcontroller A) is detected by a power detection unit (not shown). That is, the power detection unit detects whether the power from the battery 122 is supplied to the drive motor 123 or the microcontroller A (such as the drive control unit 220 (described later)).

[0048] The power detection unit may, for example, monitor (monitor) the terminal voltage (potential difference) of the battery 122 and detect whether power is being supplied. The power detection unit may detect that power is not being supplied (power loss) when the terminal voltage becomes less than or equal to a threshold value. Also, the power detection unit may monitor the current from the battery 122 and detect whether power is being supplied. The power detection unit may detect that power is not being supplied (power loss) when the current becomes less than or equal to a threshold value.

[0049] In the event of a power loss in the battery 122, the power supply may be switched by a power switching unit (not shown). As described above, when the power detection unit detects a power loss in the battery 122, the power switching unit controls the supply of regenerative power generated from the drive motor 123 to the microcontroller A (drive control unit 220 (described later), etc.).

[0050] The power switching unit is located, for example, between the battery 122 and the microcontroller A, and when power is supplied from the battery 122, it supplies power from the battery 122 to the microcontroller A, etc. When there is no power supply from the battery 122 (after the power detection unit detects power loss), it may supply regenerative power generated from the drive motor 123 to the microcontroller A, etc.

[0051] Alternatively, depending on the voltage difference between the voltage of the battery 122 and the voltage of the regenerative power generated from the drive motor 123, the system may automatically supply the regenerative power generated from the drive motor 123 to the microcontroller A, etc., when there is no power supply from the battery 122. For example, when there is power supply from the battery 122, a capacitor or the like may be arranged so that the voltage on the battery 122 side is higher than the voltage on the regenerative power side generated from the drive motor 123, so that when there is power supply from the battery 122, power is supplied from the battery 122 to the microcontroller A, etc. (regenerative power is not supplied to the microcontroller A, etc.), and when the power supply from the battery 122 is lost, the regenerative power may be supplied to the microcontroller A, etc. In other words, when there is power supply from the battery 122, the battery 122 takes priority over the regenerative power, and power from the battery 122 is supplied to the microcontroller A, etc., and when there is no power supply from the battery 122, the regenerative power may be supplied to the microcontroller A, etc. In a configuration that switches automatically, one could say that there is no power switching unit, or one could say that the automatic switching configuration itself is the power switching unit.

[0052] Furthermore, the detection of power loss from the battery 122 is not limited to monitoring voltage or current. If the battery 122 is not properly housed in the battery cover 122a, power from the battery 122 will not be supplied to the drive motor 123 or the microcontroller A (i.e., power loss will occur). Therefore, it is also possible to detect whether the battery 122 is properly housed in the battery cover 122a. For example, various sensors (e.g., photosensors, proximity sensors, image sensors, etc.) may be used to detect whether the battery 122 is properly housed in the battery cover 122a (i.e., to detect power loss).

[0053] The control unit 200 includes a mode control unit 210 and a drive control unit 220. The drive control unit 220 includes a normal control unit 221 and an abnormal control unit 222.

[0054] The mode control unit 210 controls (manages) the operating mode according to the operation of the power switch 121 and the status (presence or absence) of the power supply. The mode control unit 210 has the function of updating and referencing the value of a flag, but since the value of the flag is related to determining (specifying) the destination operating mode and, as will be described later, also determining (specifying) the current operating mode, the mode control unit 210 may also be called the operating mode determination unit. The electric vehicle 100 has the following operating modes: power OFF mode M1, power ON mode M2, no power mode M3, and abnormal brake mode M4 (see Figure 3).

[0055] The drive control unit 220 controls the drive of the drive motor 123 according to the operating mode (specifically, when it is in power ON mode M2 ​​or abnormal brake mode M4).

[0056] The normal control unit 221 controls the drive motor 123 during normal operation (when the power is ON mode M2) by performing forward assist control, reverse brake control, and forward brake control in accordance with the operating force applied to the operating grip 131 (the value detected by the grip sensor 140). The reverse brake control and forward brake control performed by the normal control unit 221 are brake controls based on the operator's operation.

[0057] The abnormality control unit 222 performs abnormal brake control as a control of the drive motor 123 in the event of an abnormality (when abnormal brake mode M4 is in operation). The abnormal brake control by the abnormality control unit 222 is brake control that is not performed by the operator. The braking force of the abnormal brake control may be set to the maximum (full brake).

[0058] In other words, both the normal control unit 221 and the abnormal control unit 222 perform brake control, although they are of different types. Specifically, the normal control unit 221 performs brake control (reverse brake control, forward brake control) according to the operating force applied to the operating grip 131. The abnormal control unit 222 performs brake control (abnormal brake control) that is unrelated to the operating force applied to the operating grip 131. In addition, the normal control unit 221 also performs assist control (forward assist control, reverse assist control) according to the operating force applied to the operating grip 131.

[0059] The grip sensor 140 detects the operating force (operating direction, operating amount) applied to the operating grip 131 and outputs the detected value to the drive control unit 220 (normal control unit 221).

[0060] The memory unit 300 stores various types of information. For example, the memory unit 300 stores flags (for example, a power OFF flag (described later)) that are stored (updated) and referenced by the mode control unit 210.

[0061] In addition to the non-volatile memory unit 300, the electric vehicle 100 may also be equipped with a volatile memory unit (not shown).

[0062] (Operating Modes) Figure 3 is an explanatory diagram illustrating the operating modes controlled by the control unit 200. The power OFF flag is a flag that is set by the power OFF operation of the power switch 121. For example, the mode control unit 210 updates the power OFF flag in the non-volatile memory unit 300 from value "0 (absent)" to "1 (present)" based on the power OFF operation of the power switch 121. The normal ON flag is a flag that is set by the power ON operation of the power switch 121. For example, the mode control unit 210 updates the normal ON flag in the volatile memory unit (not shown) from value "0 (absent)" to "1 (present)" based on the power ON operation of the power switch 121.

[0063] Power OFF mode M1 is a state (mode) where power is supplied to the microcontroller A but the power is off. In power OFF mode M1, the drive of the drive motor 123 is not controlled. Power OFF mode M1 is a mode (free state) in which assist control and brake control are intentionally not performed in order to make it easier to move the electric vehicle 100. In other words, the control unit 200 does not perform assist control (forward assist control, reverse assist control) or brake control (reverse brake control, forward brake control, abnormal brake control). In power OFF mode M1, the value of the power OFF flag is "1 (present)". In power OFF mode M1, the value of the normal ON flag is "0 (absent)".

[0064] Power ON mode M2 ​​is a state in which power is supplied to the microcontroller A, and is a power-on state (mode). In power ON mode M2, the drive of the drive motor 123 is controlled as normal control. Specifically, in power ON mode M2, the control unit 200 (normal control unit 221) performs forward assist control, reverse brake control, reverse assist control, and forward brake control according to the detected values ​​(operation direction, operation amount) of the grip sensor 140. In other words, power ON mode M2 ​​is an operating mode in which the drive motor 123 supports the comfortable driving of the electric vehicle 100. In power ON mode M2, the power (electromotive force) supplied to the drive motor 123 is converted into thermal energy by a resistor and consumed. This power may be stored in the battery 122. In other words, in power ON mode M2, the drive motor 123 may function as a regenerative brake. In power ON mode M2, the value of the power OFF flag is "0 (none)". In power-on mode M2, the value of the normal ON flag is "1 (present)".

[0065] Powerless mode M3 is a state (mode) in which no power is supplied to the microcontroller A. In powerless mode M3, there is no power supply to the microcontroller A, and the control unit 200 does not operate, so naturally the drive motor 123 is not controlled. In powerless mode M3, the value of the power OFF flag can be either "0 (none)" or "1 (present)". When transitioning from power ON mode M2 ​​to powerless mode M3 (transition T3), or when transitioning from abnormal brake mode M4 to powerless mode M3 (transition T9), the value of the power OFF flag is "0 (none)". When transitioning from power OFF mode M1 to powerless mode M3 (transition T6), the value of the power OFF flag is "1 (present)". In powerless mode M3, the value of the normal ON flag is "0 (none)". The normal ON flag is stored in a volatile memory unit (not shown), so it is automatically cleared when the power supply is cut off.

[0066] The abnormal brake mode M4 is a state (mode) in which power is supplied to the microcontroller A and it is an abnormal (emergency) state. In abnormal brake mode M4, the drive of the drive motor 123 is controlled as an abnormal control measure. Specifically, in abnormal brake mode M4, the control unit 200 (abnormal control unit 222) performs abnormal brake control. In other words, abnormal brake mode M4 is an operating mode that ensures the safety of the electric vehicle 100's operation by the drive motor 123. In abnormal brake mode M4, the value of the power OFF flag is "0 (none)". In abnormal brake mode M4, the value of the normal ON flag is "0 (none)".

[0067] (Power OFF mode M1 → Power ON mode M2; Transition T1) The condition for transitioning from power OFF mode M1 to power ON mode M2 ​​T1 is a power-on operation. In transition T1, the mode control unit 210 updates (clears) the value of the power OFF flag from "1 (present)" to "0 (absent)". In transition T1, the mode control unit 210 updates (sets) the value of the normal ON flag from "0 (absent)" to "1 (present)".

[0068] (Power ON mode M2 ​​→ Power OFF mode M1; Transition T2) The condition for transitioning from power ON mode M2 ​​to power OFF mode M1 T2 is a power-off operation. The transition from power ON mode M2 ​​to power OFF mode M1 may also occur by auto power-off. In transition T2, the mode control unit 210 updates the value of the power OFF flag from "0 (absent)" to "1 (present)". In transition T2, the mode control unit 210 updates the value of the normal ON flag from "1 (present)" to "0 (absent)".

[0069] (Power ON mode M2 ​​→ Power off mode M3; Transition T3) The condition for transitioning from power ON mode M2 ​​to power off mode M3 T3 is that the power supply to microcontroller A ends. In other words, power supply goes from on to off. As mentioned above, power is supplied to microcontroller A by battery 122 and by drive motor 123 (back electromotive force). In other words, if battery 122 is not installed and the electric vehicle 100 is not moving, no power is supplied to microcontroller A. In other words, in power ON mode M2, if battery 122 is not installed and the electric vehicle 100 is not moving, the system transitions to power off mode M3. In transition T3, the mode control unit 210 does not update the value of the power OFF flag. In other words, the value of the power OFF flag "0 (none)" is maintained. In transition T3, the value of the volatile normal ON flag is cleared (becomes "0 (none)").

[0070] (Powerless mode M3 → Power OFF mode M1; transition T4) The conditions for transitioning from powerless mode M3 to power OFF mode M1 T4 are that power supply to the microcontroller A begins and the value of the power OFF flag is "1 (present)". In other words, if the power supply changes from no power to power supply and the value of the power OFF flag in the memory unit 300 is "1 (present)", the system transitions from powerless mode M3 to power OFF mode M1. As described above, power is supplied to the microcontroller A by the battery 122 and by the drive motor 123 (back electromotive force). In other words, power is supplied to the microcontroller A when the battery 122 is installed or when the electric vehicle 100 is moving. In other words, in power-off mode M3, if the battery 122 is installed or the electric vehicle 100 is in a moving state (when a back electromotive force (regenerative power) is generated in the drive motor 123 due to the rotation of the drive wheels 124), and the value of the power OFF flag is "1 (present)", then the system transitions to power OFF mode M1. Note that the value of the power OFF flag being "1 (present)" means that there was a transition T6 from power OFF mode M1 to power-off mode M3 before the transition T4. In transition T4, the mode control unit 210 does not update the value of the power OFF flag. In other words, the value of the power OFF flag "1 (present)" is maintained. In transition T4, the mode control unit 210 does not update the value of the normal ON flag.

[0071] (No power mode M3 → Abnormal brake mode M4; transition T5) The conditions for transitioning from no power mode M3 to abnormal brake mode M4 T5 are that power is supplied to the microcontroller A and the value of the power OFF flag is "0 (none)". In other words, if the power supply changes from no power to power supply and the value of the power OFF flag in the memory unit 300 is "0 (none)", the system transitions from no power mode M3 to abnormal brake mode M4. As described above, power is supplied to the microcontroller A by the battery 122 and by the drive motor 123 (back electromotive force). In other words, power is supplied to the microcontroller A when the battery 122 is installed or when the electric vehicle 100 is moving. In other words, in the no-power mode M3, if the battery 122 is installed or the electric vehicle 100 is in a moving state (when a back electromotive force (regenerative power) is generated in the drive motor 123 due to the rotation of the drive wheels 124), and the value of the power OFF flag is "0 (none)", the system transitions to abnormal brake mode M4. The case where the value of the power OFF flag is "0 (none)" means that before the transition T5, there was a transition T3 from power ON mode M2 ​​to no-power mode M3 (or a transition T9 from abnormal brake mode M4 to no-power mode M3). In transition T5, the mode control unit 210 does not update the value of the power OFF flag. In other words, the value of the power OFF flag "0 (none)" is maintained. In transition T5, the mode control unit 210 does not update the value of the normal ON flag.

[0072] (Power OFF mode M1 → No power mode M3; transition T6) The condition for transitioning from power OFF mode M1 to no power mode M3 T6 is that the power supply to microcontroller A ends. In other words, in power OFF mode M1, when the battery 122 is not installed and the electric vehicle 100 is not moving, the system transitions to no power mode M3. In transition T6, the mode control unit 210 does not update the value of the power OFF flag. In other words, the value of the power OFF flag "1 (present)" is maintained. In transition T6, the mode control unit 210 does not update the value of the normal ON flag.

[0073] (Power ON mode M2 ​​→ Abnormal brake mode M4; transition T7) The condition for transitioning from power ON mode M2 ​​to abnormal brake mode M4 T7 is when the power supply to the microcontroller A decreases (for example, when the position of the battery 122 inside the battery cover 122a shifts due to vibration, etc., causing poor contact and resulting in a power supply below a predetermined threshold). In other words, in power ON mode M2, if the power supply is maintained but falls below a predetermined threshold, the system transitions to abnormal brake mode M4. In transition T7, the mode control unit 210 does not update the value of the power OFF flag. In other words, the value of the power OFF flag, "0 (none)", is maintained. In transition T7, the mode control unit 210 updates the value of the normal ON flag from "1 (present)" to "0 (absent)".

[0074] (Abnormal brake mode M4 → Power OFF mode M1; Transition T8) The condition for transitioning from abnormal brake mode M4 to power OFF mode M1 T8 is a power-off operation. Note that the transition from abnormal brake mode M4 to power OFF mode M1 (transition T8) is sometimes referred to as the release of the abnormal brake. In transition T8, the mode control unit 210 updates the value of the power OFF flag from "0 (none)" to "1 (present)". In transition T8, the mode control unit 210 does not update the value of the normal ON flag.

[0075] (Abnormal Brake Mode M4 → No Power Mode M3; Transition T9) The condition for transitioning from abnormal brake mode M4 to no power mode M3 T9 is that the power supply to the microcontroller A ends. In other words, in abnormal brake mode M4, if the battery 122 is not installed and the electric vehicle 100 is not moving, the system transitions to no power mode M3. For example, in abnormal brake mode M4, if the drive wheels 124 stop or the electric vehicle 100 becomes not moving due to abnormal braking. In transition T9, the mode control unit 210 does not update the value of the power OFF flag. In other words, the value of the power OFF flag "0 (none)" is maintained. In transition T9, the mode control unit 210 does not update the value of the normal ON flag.

[0076] The power OFF flag and normal ON flag are flags whose values ​​change when transitioning from one specific operating mode to another. However, the current operating mode can also be identified by the presence or absence of power (whether or not power is supplied) and the values ​​of the power OFF flag and normal ON flag. Specifically, if there is no power, power OFF mode M3 is identified. In the three operating modes with power (power OFF mode M1, power ON mode M2, and abnormal brake mode M4), if the value of the power OFF flag is "1 (present)", power OFF mode M1 is identified. If the value of the power OFF flag is "0 (absent)" and the value of the normal ON flag is "1 (present)", power ON mode M2 ​​is identified. If the value of the power OFF flag is "0 (absent)" and the value of the normal ON flag is "0 (absent)", abnormal brake mode M4 is identified.

[0077] Figure 4 is a flowchart showing an example of the operation when transitioning from power-off mode M1 to other operating modes.

[0078] The control unit 200 (mode control unit 210) determines whether a power-on operation has occurred (step S10). If there is no power-on operation (step S10: NO), the process returns to step S10. If a power-on operation has occurred (step S10: YES), the control unit 200 updates the value of the power-off flag from "1 (present)" to "0 (absent)" (step S11), updates the value of the normal-on flag from "0 (absent)" to "1 (present)" (step S12), and transitions to power-on mode M2 ​​(transition T1).

[0079] Although not shown in Figure 4, if the power supply is cut off in power OFF mode M1, the system transitions to powerless mode M3 (transition T6).

[0080] Figure 5 is a flowchart showing an example of the operation when transitioning from power-on mode M2 ​​to other operating modes.

[0081] The control unit 200 (for example, the mode control unit 210) determines in step S20 whether there has been a power drop. If there is no power drop (step S20: NO), the control unit 200 (mode control unit 210) determines whether there has been a power-off operation (step 21). If there has been no power-on operation (step S21: NO), the process returns to step S20.

[0082] If a power-on operation is performed (step S21: YES), the control unit 200 (mode control unit 210) updates the value of the power-off flag from "0 (absent)" to "1 (present)" (step S22), updates the value of the normal-on flag from "1 (present)" to "0 (absent)" (step S23), and transitions to power-off mode M1 (transition T2).

[0083] If a power drop occurs (step S20: NO), the control unit 200 (mode control unit 210) updates the value of the normal ON flag from "1 (present)" to "0 (absent)" (step S24) and transitions to abnormal brake mode M4 (transition T7).

[0084] Although not shown in Figure 5, if the power supply is lost in power-on mode M2, the system transitions to power-off mode M3 (transition T3).

[0085] Figure 6 is a flowchart illustrating an example of the operation when transitioning from power-off mode M3 to other operating modes. The flowchart in Figure 6 begins when power is supplied.

[0086] The control unit 200 (mode control unit 210) determines whether the value of the power OFF flag is "1 (present)" (step S30). If the value of the power OFF flag is "1 (present)" (step S30: YES), the system transitions to power OFF mode M1 (transition T4). If the value of the power OFF flag is "0 (absent)" (step S30: NO), the system transitions to abnormal brake mode M4 (transition T5).

[0087] Figure 7 is a flowchart showing an example of the operation when transitioning from abnormal braking mode M4 to another operating mode.

[0088] The control unit 200 (mode control unit 210) determines whether a power-off operation has occurred (step 40). If no power-off operation has occurred (step S40: NO), the process returns to step S40. If a power-off operation has occurred (step S40: YES), the control unit 200 (mode control unit 210) updates the value of the power-off flag from "0 (none)" to "1 (present)" (step S43) and transitions to power-off mode M1 (transition T8). In other words, the abnormal brake is released by the power-off operation.

[0089] Although not shown in Figure 7, if the power supply is lost in abnormal braking mode M4, the system transitions to powerless mode M3 (transition T9).

[0090] (Other embodiments regarding the release of abnormal brakes) It has been explained that the system transitions from abnormal brake mode M4 to power OFF mode M1 (releases the abnormal brakes) on the condition of a power-off operation, but the system may also transition from abnormal brake mode M4 to power OFF mode M1 (releases the abnormal brakes) on the condition of other conditions. For example, if the direction of movement of the electric vehicle 100 and the direction of push-pull operation of the operating grip 131 (direction of displacement of the operating grip 131) coincide, and the amount of push-pull operation of the operating grip 131 (amount of displacement of the operating grip 131) is greater than or equal to a threshold, the system may transition from abnormal brake mode M4 to power OFF mode M1.

[0091] Figure 8 shows an example of another configuration of the electric vehicle 100, including the control unit 200. As shown in Figure 8, the control unit 200 further includes a mode control unit 210 and a drive control unit 220, as well as a movement direction determination unit 230 and a release determination unit 240. The movement direction determination unit 230 determines the rotation direction of the drive wheel 124 (i.e., the movement direction of the electric vehicle 100) based on the output value from the encoder (an encoder connected to the drive motor 123) of the drive motor 123. The release determination unit 240 determines whether or not to release the abnormal brake based on the determination result of the movement direction determination unit 230 (the movement direction of the electric vehicle 100) and the detected value of the grip sensor 140 (the pushing and pulling operation direction of the operating grip 131, and the amount of pushing and pulling operation of the operating grip 131). Specifically, the movement direction determination unit 230 determines that it is necessary to release the abnormal brake if the movement direction of the electric vehicle 100 matches the push / pull operation direction of the operating grip 131, and the amount of push / pull operation of the operating grip 131 is greater than or equal to a threshold. Based on the determination result of the release determination unit 240, the mode control unit 210 transitions from abnormal brake mode M4 to power OFF mode M1 (releases the abnormal brake).

[0092] Figure 9 is a flowchart showing an example of other operations when transitioning from abnormal braking mode M4 to other operating modes.

[0093] The control unit 200 (mode control unit 210) determines whether a power-off operation has occurred (step 40). If there is no power-off operation (step S40: NO), the control unit 200 (movement direction determination unit 230) determines whether the movement direction of the electric vehicle 100 matches the push-pull operation direction of the operating grip 131 (step S41). If the movement direction of the electric vehicle 100 matches the push-pull operation direction of the operating grip 131 (step S41: YES), the control unit 200 (movement direction determination unit 230) determines whether the amount of operation of the operating grip 131 is greater than or equal to a threshold (step S42).

[0094] If the direction of movement of the electric vehicle 100 does not match the direction of push-pull operation of the operating grip 131 (step S41: NO), or if the amount of operation of the operating grip 131 is not equal to or greater than a threshold (step S42: NO), the process returns to step S40.

[0095] If a power-off operation is performed (step S40: YES), or if the amount of operation of the operating grip 131 is greater than or equal to a threshold (step S42: YES), the control unit 200 (mode control unit 210) updates the value of the power-off flag from "0 (none)" to "1 (present)" (step S43), and transitions to power-off mode M1 (transition T8). In other words, the abnormal brake is released by the power-off operation.

[0096] As described above, according to the embodiment, users can use the device safely even if there is an abnormality in the power supply from the battery.

[0097] The power-off operation is performed consciously by the operator. In other words, the power loss of battery 122 after the operator's power-off operation (power loss transitioning from power-on mode M2 ​​→ power-off mode M1 → no-power mode M3) is a power loss intended by the operator. On the other hand, the battery 122 falling out or the power wire breaking are not done consciously by the operator. In other words, the power loss of battery 122 due to the battery 122 falling out or the power loss transitioning from power-on mode M2 ​​→ no-power mode M3 is a power loss not intended by the operator.

[0098] In the event of an unintended power loss by the operator, regenerative power is used to perform abnormal brake control. For example, even if power (motor) is lost while the electric vehicle 100 is running due to the battery 122 falling out or the power line being cut, power is supplied to the circuit board (microcontroller A) by the back electromotive force (regenerative power) of the drive motor 123, and abnormal brake control is performed, thus ensuring the safety of the user. As a specific example, if the battery 122 falls out while the vehicle is climbing a steep slope with assist control in power ON mode M2, the operating mode will transition from power ON mode M2 ​​to power off mode M3 (transition T3). The next moment, the wheels (drive wheels 124) will rotate as if rolling down the steep slope, and power will be supplied to the microcontroller A by the back electromotive force of the drive motor 123, and the operating mode will transition from power off mode M3 to abnormal brake mode M4 (transition T5). In abnormal brake mode M4, abnormal brake control is performed, and abnormal brakes are applied on the steep slope, ensuring safety. In other words, if the battery 122 falls out on a slope or the like, the system transitions from power ON mode M2 ​​to power off mode M3 (transition T3). In power off mode M3, if the drive wheels 124 rotate and power is supplied to the microcontroller A by the back electromotive force of the drive motor 123, the value of the power OFF flag is "0 (none)". Therefore, the system transitions from power off mode M3 to abnormal brake mode M4 (transition T5), and safety is ensured by the abnormal brake.

[0099] In the event of an intentional power loss by the operator, abnormal brake control is disabled to ensure convenience. For example, after a power-off operation, the system transitions from power-on mode M2 ​​→ power-off mode M1 → no-power mode M3. In no-power mode M3, if the drive wheels 124 rotate and power is supplied to the microcontroller A by the back electromotive force of the drive motor 123, the value of the power-off flag is "1 (present)," so the system transitions from no-power mode M3 to power-off mode M1 (transition T6). Therefore, if the power is turned off intentionally, even if the electric vehicle 100 is moved (the drive wheels 124 are rotated), abnormal brakes will not be applied, making it easier to carry the electric vehicle 100. In this embodiment, whether or not a power-off operation has occurred is managed (determined) using the power-off flag.

[0100] According to this embodiment, by focusing on whether or not the power has been turned OFF (using a power OFF flag), it is possible to avoid dangers such as the battery 122 falling out while driving on slopes by abnormal brake control, while ensuring the operability of the electric vehicle 100, such as carrying it.

[0101] Furthermore, the system transitions from abnormal brake mode M4 to power OFF mode M1 (transition T8). In other words, the release of the abnormal brake is primarily done by turning off the power (Figures 3 and 7). However, in addition to turning off the power, the system is also configured to transition from abnormal brake mode M4 to power OFF mode M1 (transition T8) if the direction of movement and the direction of operation coincide and the amount of operation exceeds a threshold (Figures 8 and 9). This allows the system to easily move the electric vehicle 100 to a safe location, even in situations where there is no time to turn off the power, such as when the vehicle is stuck at a level crossing, by applying a certain operating force in a certain direction (for example, towards a safe place), the abnormal brake that was hindering the movement of the electric vehicle 100 to a safe place will be released.

[0102] As mentioned above, even if power is lost due to the battery 122 falling out or the like while the electric vehicle 100 is running, power is restored by the back electromotive force of the drive motor 123, and the abnormal brake is applied, so it is basically safe. However, the state in which the abnormal brake is applied is not necessarily safe, and there are cases in which it is desirable to immediately release the abnormal brake (for example, when the vehicle is stuck at a level crossing). When stuck at a level crossing, for example, one is in a panic and does not have the psychological capacity to turn off the power (and if the power off operation is a long press operation, there is even less time to spare). In the examples shown in Figures 8 and 9, even without turning off the power, if the direction of movement and the direction of operation coincide and the amount of operation is above a threshold, the abnormal brake can be released, so the abnormal brake can be released immediately.

[0103] Furthermore, the program for realizing the electric vehicle 100 (control unit 200, etc.) described above may be stored in a computer-readable storage medium, and the program may be loaded into a computer system and executed. Here, "computer system" includes hardware such as the OS and peripheral devices. "Computer-readable storage medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, and storage devices such as hard disks built into a computer system. Moreover, "computer-readable storage medium" also includes volatile memory (RAM) inside a computer system that acts as a server or client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line, which holds the program for a certain period of time. Furthermore, the above program may be transmitted from the computer system that stores the program in a storage device, etc., to another computer system via a transmission medium or by transmission waves in the transmission medium. Here, the "transmission medium" for transmitting the program refers to a medium that has the function of transmitting information, such as a network such as the Internet or a communication line such as a telephone line. Furthermore, the above program may be for realizing only a part of the functions described above. Furthermore, the aforementioned functions may be implemented in combination with programs already stored in the computer system, such as so-called differential files (differential programs).

[0104] While embodiments of this invention have been described in detail above with reference to the drawings, the specific configuration is not limited to these embodiments and includes designs and the like that do not depart from the spirit of this invention.

[0105] For example, in the above embodiment, the power OFF mode M1 was described as a free state, but any brake may be set. For example, similar to the power ON mode M2, brake control may be performed according to the operating force.

[0106] In the above embodiment, the braking force in abnormal braking mode M4 (the braking force for abnormal braking control) was described as full braking, but it may be any braking force. For example, an intermediate braking force may be controlled by turning a Field Effect Transistor (FET) ON / OFF.

[0107] In the above embodiment, it was explained that the abnormal brake (full brake) is released (no brake), but since releasing it suddenly is dangerous, the brake force may be gradually reduced before releasing it.

[0108] The system may be controlled in the following sequence: abnormal brake mode M4 → power OFF mode M1 → power ON mode M2. In this case, the braking force may be controlled in the following sequence: full brake in abnormal brake mode M4 → weak brake in abnormal brake mode M4 → power OFF mode M1 (no brake control) → brake control in power ON mode M2.

[0109] Furthermore, if the direction of movement of the vehicle body coincides with the operating direction of the operating grip 131 and the operating force of the operating grip 131 is greater than or equal to a predetermined threshold, then after transitioning from abnormal brake mode M4 to no-power mode M3, if there is an operating force greater than or equal to a predetermined threshold in the operating direction opposite to the operating direction when the brake was released, the system may transition from no-power mode M3 to abnormal brake mode M4.

[0110] In the above embodiment, examples were described in which the abnormal brake is released when the power is turned OFF (condition 1), and when the direction of movement of the vehicle body and the direction of operation of the operating grip 131 coincide and the operating force of the operating grip 131 is greater than or equal to a predetermined threshold (condition 2). However, the conditions for releasing the abnormal brake are not limited to these. For example, the condition may be that a predetermined operation of the operating grip 131 (for example, an operation to push in the operating grip 131) is performed repeatedly. As an example, even if neither condition 1 nor condition 2 is met, the abnormal brake may be released if the operation to push in the operating grip 131 is repeated a predetermined number of times (for example, 5 times) within a predetermined time (for example, 5 seconds). As another example, even if condition 1 is not met, the abnormal brake may be released if the operation to push in the operating grip 131, which coincides with the direction of movement of the vehicle body and whose operating force is greater than or equal to a predetermined threshold, is repeated a predetermined number of times within a predetermined time.

[0111] Although not explained in the above embodiment, abnormal braking control may be performed when the electric vehicle 100 is tilted (when it is on a slope) (it may also transition to abnormal braking mode M4). For example, the electric vehicle 100 may be equipped with a tilt angle sensor and an inertial measurement unit and perform abnormal braking control according to the tilt angle. As an example, the electric vehicle 100 may perform abnormal braking control when there is an abnormality in the power supply from the battery 122 and the tilt angle is greater than or equal to a predetermined tilt angle (first tilt angle). This can suitably ensure the safety of the user (when there is an abnormality in the power supply from the battery 122 on a sloped surface, etc.). As another example, the electric vehicle 100 may perform abnormal braking control even if there is no abnormality in the power supply from the battery 122, if the tilt angle is greater than or equal to a predetermined tilt angle (second tilt angle greater than the first tilt angle). This can ensure the safety of the user on a dangerous sloped surface.

[0112] In the above embodiment, an example was described in which the status of operation by the power switch 121 (operation result) is managed electronically and informationally (stored as the values ​​of the power OFF flag and the normal ON flag). However, it is sufficient that the status of operation by the power switch 121 can be recognized even after the operation, and it may be managed structurally or mechanically, for example.

[0113] In the above embodiment, an example was described in which the power on / off operation is performed using the power switch 121 provided on the electric vehicle 100. However, the power on / off operation may also be performed using a communication device that can communicate with the electric vehicle 100 (for example, a keyless key, smart key, smartphone, etc.).

[0114] Furthermore, notification may be given when the battery 122 has lost power. For example, the electric vehicle 100 may be equipped with a light-emitting element (LED, etc.) and, in the event of a power loss of the battery 122, the system may notify the operator of the power loss by flashing or lighting up. Alternatively, the electric vehicle 100 may be equipped with an audio output unit and, in the event of a power loss of the battery 122, the system may notify the operator of the power loss by voice (message, alert sound). In addition, when the battery 122 has lost power, a communication device (as described above) capable of communicating with the electric vehicle 100 may be notified of the power loss of the battery 122, and the notification device may notify the operator of the power loss of the battery 122 (by illumination, sound, display). This allows the operator and those around them to recognize that the battery 122 has lost power and that the system is performing different control actions than usual due to the power loss of the battery 122. The same applies to controls A to C described below.

[0115] In the above embodiment, the transition from power-off mode M3 was described as a transition from power-off mode M3 to power-off mode M1 (transition T4) and a transition from power-off mode M3 to abnormal brake mode M4 (transition T5), but the transition from power-off mode M3 to power-on mode M2 ​​was not described. However, the transition from power-off mode M3 to power-on mode M2 ​​may also be described. The transition from power-off mode M3 to power-on mode M2 ​​will now be described. Specifically, for example, the control is performed as one of the following (control A) to (control C).

[0116] (Control A) If power is supplied in the no-power mode M3 (for example, if a back electromotive force (regenerative power) is generated by the rotation of the drive wheels 124), the system will transition from no-power mode M3 to power-on mode M2, regardless of the value of the power OFF flag. In other words, even when the value of the power OFF flag is "1 (present)" (in the case of power loss intended by the operator, even when transitioning from power-on mode M2 ​​→ power-off mode M1 → no-power mode M3), and even when the value of the power OFF flag is "0 (absent)" (in the case of power loss not intended by the operator, even when transitioning from power-on mode M2 ​​→ no-power mode M3), the system will transition from no-power mode M3 to power-on mode M2, for example, due to regenerative power. In other words, regardless of whether the power loss was intended by the operator, if regenerative power is supplied, for example, assist control (forward assist control, reverse assist control) or brake control (reverse brake control, forward brake control) will be executed.

[0117] (Control B) In the no-power mode M3, if power is supplied (for example, if a back electromotive force (regenerative power) is generated by the rotation of the drive wheels 124), the system will transition from no-power mode M3 to power-on mode M2 ​​if the value of the power OFF flag is "1 (Yes)". In other words, if the power loss was intentional on the part of the operator, for example, if regenerative power is supplied, assist control (forward assist control, reverse assist control) or brake control (reverse brake control, forward brake control) will be executed.

[0118] Furthermore, if power is supplied in power-off mode M3, and the value of the power OFF flag is "0 (none)", the system may transition from power-off mode M3 to abnormal brake mode M4 (power ON mode M2 ​​→ power-off mode M3 → abnormal brake mode M4), or from power-off mode M3 to power OFF mode M1 (power ON mode M2 ​​→ power-off mode M3 → power OFF mode M1).

[0119] (Control C) In the no-power mode M3, if power is supplied (for example, if a back electromotive force (regenerative power) is generated by the rotation of the drive wheels 124), the system will transition from no-power mode M3 to power-on mode M2 ​​if the value of the power OFF flag is "0 (none)". In other words, if the power loss is not intentional on the part of the operator, for example, if regenerative power is supplied, assist control (forward assist control, reverse assist control) or brake control (reverse brake control, forward brake control) will be executed.

[0120] Furthermore, if power is supplied in powerless mode M3, and the value of the power OFF flag is "1 (Yes)" (indicating that the power loss was intentional on the part of the operator), the system may transition from powerless mode M3 to power OFF mode M1 (power ON mode M2 ​​→ power OFF mode M1 → powerless mode M3 → power OFF mode M1), or from powerless mode M3 to abnormal brake mode M4 (power ON mode M2 ​​→ power OFF mode M1 → powerless mode M3 → abnormal brake mode M4).

[0121] The electric vehicle 100 of this embodiment has, for example, the following configuration: wheels (drive wheels 124) provided on the vehicle body, a motor (drive motor 123) that rotates the wheels using power supplied from a battery (battery 122), a grip part (operating grip 131) that detects the operating force applied by the user, and a drive control unit (drive control unit 220) that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip part. The drive control unit can perform the assist control by controlling the drive of the motor using regenerative power generated from the motor as the wheels rotate when the battery loses power (as described in Controls A to C above).

[0122] The vehicle comprises a wheel (drive wheel 124) mounted on the vehicle body, a motor (drive motor 123) that rotates the wheel using power supplied from a battery (battery 122), a grip (operating grip 131) that detects the operating force applied by the user, a drive control unit (drive control unit 220) that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip, a power detection unit that detects whether power from the battery is supplied to the motor or the drive control unit, and a power switching unit that, when the power detection unit detects that power is not being supplied, controls the supply of regenerative power generated from the motor by the rotation of the wheel to the drive control unit (the part described in Controls A to C above).

[0123] The vehicle comprises wheels (drive wheels 124) mounted on the vehicle body, a battery (battery 122) that supplies power, a motor (drive motor 123) that rotates the wheels, a grip part (operating grip 131) that the user grasps and detects the operating force, a drive control unit (drive control unit 220) that controls the drive of the motor and can perform assist control and brake control according to the operating force of the grip part, as well as abnormal brake control, an ON operation that switches from an OFF state where assist control and brake control according to the operating force of the grip part are not performed, to an ON state where assist control and brake control according to the operating force of the grip part are performed, and an OFF operation that switches from the ON state to the OFF state. The motor comprises a switch unit (power switch 121) capable of receiving an OFF operation, the motor generates regenerative power by the rotation of the wheels (see Figures 2 and 8), and the drive control unit, when the regenerative power supply is started, does not execute the abnormal brake control (transitions from no-power mode M3 to power OFF mode M1) if the switch unit had received the OFF operation before the regenerative power supply was started, and when the regenerative power supply is started, executes the abnormal brake control (transitions from no-power mode M3 to abnormal brake mode M4), the electric vehicle (electric vehicle 100).

[0124] The system includes a flag control unit (mode control unit 210) that controls a predetermined flag (power OFF flag) stored in a non-volatile memory unit. The flag control unit clears the predetermined flag when the switch unit receives the ON operation (step S11 in Figure 4) and sets the predetermined flag when the switch unit receives the OFF operation (step S22 in Figure 5). The drive control unit does not perform the abnormal brake control when the predetermined flag is set at the start of regenerative power supply, and performs the abnormal brake control when the predetermined flag is not set at the start of regenerative power supply.

[0125] Information on when and where the abnormal brake control was performed may be stored in a non-volatile memory unit. When investigating malfunctions of the electric vehicle using this information, it is possible to consider whether the tendency for battery loss is due to a structural problem, an external factor such as the time, place, or weather in which it is likely to occur, or a problem with the battery installation method by the user. The electric vehicle 100 may also be equipped with a location information acquisition unit such as GPS, and information on where the abnormal brake control was performed may be stored in a non-volatile memory unit.

[0126] When the drive control unit is performing the abnormal brake control (in abnormal brake mode M4), it stops the execution of the abnormal brake control (releases the abnormal brake) in response to the switch unit receiving the OFF operation. In other words, the operating mode transitions from abnormal brake mode M4 to power OFF mode M1 (see Figures 2 and 7).

[0127] When the drive control unit is performing the abnormal brake control (in abnormal brake mode M4), if the direction of movement of the vehicle body and the operating direction of the grip part coincide and the operating force of the grip part is greater than or equal to a predetermined threshold, the drive control unit stops the execution of the abnormal brake control (releases the abnormal brake). In other words, the operating mode transitions from abnormal brake mode M4 to power OFF mode M1 (see Figures 8 and 9).

[0128] The drive control unit resumes the execution of the abnormal brake control if predetermined conditions are met after it has stopped executing the abnormal brake control. For example, if power is supplied again after transitioning from abnormal brake mode M4 to no-power mode M3 (after releasing the abnormal brake) (for example, if the stopped drive wheel 124 rotates again), it transitions from no-power mode M3 to abnormal brake mode M4. Also, if the direction of movement of the vehicle body and the operating direction of the grip part coincide and the operating force of the grip part is above a predetermined threshold, then if there is an operating force above a predetermined threshold in the opposite direction (the operating direction opposite to the operating direction when the abnormal brake was released) after transitioning from abnormal brake mode M4 to no-power mode M3 (after releasing the abnormal brake), it transitions from no-power mode M3 to abnormal brake mode M4.

[0129] Furthermore, the electric vehicle 100 of the embodiment has, for example, the following control device. The electric vehicle (electric vehicle 100) comprises wheels (drive wheels 124) provided on the vehicle body, a motor (drive motor 123) that rotates the wheels using power supplied from a battery (battery 122), and a grip part (operating grip 131) that detects the operating force gripped by the user. The control device (a part corresponding to the control unit 200, or a part corresponding to the drive control unit 220) controls the drive of the motor and performs assist control according to at least the operating force of the grip part. The drive control unit can perform the assist control by controlling the drive of the motor with regenerative power generated from the motor when the wheels rotate if there is a loss of power from the battery (parts described in Control A to Control C above).

[0130] A control device (a part corresponding to a control unit 200 or a drive control unit 220) for an electric vehicle (electric vehicle 100) comprising: wheels (drive wheels 124) mounted on the vehicle body; a battery (battery 122) that supplies power; a motor (drive motor 123) that rotates the wheels; a grip part (operating grip 131) that a user grips and detects the operating force; and a switch part (power switch 121) that can receive an ON operation to switch from an OFF state in which assist control and brake control according to the operating force of the grip part are not performed, to an ON state in which assist control and brake control according to the operating force of the grip part are performed, and an OFF operation to switch from the ON state to the OFF state, wherein the control device (a part corresponding to a control unit 200 or a drive control unit 220) comprises: a normal control unit (normal control unit 221) that controls the drive of the motor and performs assist control and brake control according to the operating force of the grip part, and the motor The control device (a part corresponding to the control unit 200, or a part corresponding to the drive control unit 220) includes an abnormal control unit (abnormal control unit 222) that controls the drive and performs abnormal brake control, wherein the motor generates regenerative power by the rotation of the wheels, and the abnormal control unit, when the supply of regenerative power starts, if the switch unit had accepted the OFF operation before the supply of regenerative power started (if the value of the power OFF flag was "1 (present)"), does not perform the abnormal brake control (transitions from power-off mode M3 to power-off mode M1), and when the supply of regenerative power starts, if the switch unit had not accepted the OFF operation before the supply of regenerative power started (if the value of the power OFF flag was "0 (absent)"), performs the abnormal brake control (transitions from power-off mode M3 to abnormal brake mode M4).

[0131] As previously explained, electric vehicles are not limited to electric wheelchairs.

[0132] In the embodiments and modifications disclosed herein, if multiple functions are provided in a distributed manner, some or all of those functions may be provided in a consolidated manner, and conversely, if multiple functions are provided in a consolidated manner, some or all of those functions may be provided in a distributed manner. Regardless of whether the functions are consolidated or distributed, it is sufficient that the invention's objective can be achieved.

[0133] According to the present invention, safety in the use of electric vehicles is improved.

[0134] 100...Electric vehicle, 121...Power switch, 123...Drive motor, 124...Drive wheel, 140...Grip sensor, 200...Control unit, 210...Mode control unit, 220...Drive control unit, 230...Movement direction determination unit, 240...Release determination unit, 300...Storage unit

Claims

1. An electric vehicle comprising: wheels mounted on a vehicle body; a motor that rotates the wheels using power supplied from a battery; a grip portion that detects the operating force applied by the user; and a drive control unit that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip portion, wherein, in the event of a loss of power from the battery, the drive control unit can control the drive of the motor using regenerative power generated from the motor by the rotation of the wheels, thereby enabling the execution of the assist control.

2. The electric vehicle according to claim 1, wherein the drive control unit is capable of performing abnormal brake control, which controls the brakes regardless of the operating force of the grip portion, and the drive control unit is capable of performing the abnormal brake control by controlling the drive of the motor with the regenerative power when the battery power is lost.

3. The electric vehicle according to claim 2, wherein the drive control unit controls the drive of the motor using the regenerative power to perform the abnormal brake control when there is a loss of power in the battery that was not intended by the user.

4. An electric vehicle comprising: wheels mounted on a vehicle body; a motor that rotates the wheels using power supplied from a battery; a grip section that detects the operating force applied by the user; a drive control section that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip section; a power detection section that detects whether power from the battery is supplied to the motor or the drive control section; and a power switching section that, when the power detection section detects that power is not being supplied, controls the vehicle to supply regenerative power generated from the motor by the rotation of the wheels to the drive control section.

5. The electric vehicle according to claim 4, wherein the drive control unit is capable of performing abnormal brake control, which controls the brakes regardless of the operating force of the grip unit, and the drive control unit, which is supplied with regenerative power by the control of the power switching unit, performs the abnormal brake control.

6. The drive control unit is capable of performing brake control in accordance with the operating force of the grip portion, and includes a switch portion capable of receiving an ON operation to switch from an OFF state in which assist control in accordance with the operating force of the grip portion and brake control in accordance with the operating force of the grip portion are not performed to an ON state in which assist control in accordance with the operating force of the grip portion and brake control in accordance with the operating force of the grip portion are performed, and an OFF operation to switch from the ON state to the OFF state, wherein the drive control unit does not perform the abnormal brake control when the supply of regenerative power is started if the switch portion had received the OFF operation before the supply of regenerative power was started, and performs the abnormal brake control when the supply of regenerative power is started if the switch portion had not received the OFF operation before the supply of regenerative power was started. The electric vehicle according to claim 2, claim 3, or claim 5.

7. An electric vehicle according to claim 6, comprising: a flag control unit for controlling a predetermined flag stored in a non-volatile memory unit, wherein the flag control unit clears the predetermined flag in response to the switch unit receiving the ON operation, and sets the predetermined flag in response to the switch unit receiving the OFF operation; and the drive control unit does not perform the abnormal brake control when the predetermined flag is set at the start of the supply of regenerative power, and performs the abnormal brake control when the predetermined flag is not set at the start of the supply of regenerative power.

8. The electric vehicle according to claim 6 or 7, wherein the drive control unit, when executing the abnormal brake control, stops executing the abnormal brake control in response to the switch unit receiving the off operation.

9. The electric vehicle according to any one of claims 2, 3, 5, 6, 7, or 8, wherein when the drive control unit is performing the abnormal brake control, if the direction of movement of the vehicle body and the operating direction of the grip portion coincide and the operating force of the grip portion is greater than or equal to a predetermined threshold, the electric vehicle according to any one of claims 2, 3, 5, 6, 7, or 8.

10. The electric vehicle according to any one of claims 2, 3, 5, 6, 7, 8, or 9, wherein the drive control unit resumes the execution of the abnormal brake control if a predetermined condition is met after discontinuing the execution of the abnormal brake control.

11. A control device for controlling an electric vehicle comprising wheels mounted on a vehicle body, a motor that rotates the wheels using power supplied from a battery, and a grip portion that detects the operating force applied by a user, the control device comprising: a drive control portion that controls the drive of the motor and performs assist control corresponding to at least the operating force applied by the grip portion, wherein, in the event of a loss of power from the battery, the drive control portion is capable of controlling the drive of the motor using regenerative power generated from the motor by the rotation of the wheels, thereby enabling the execution of the assist control.

12. A control device for controlling an electric vehicle comprising wheels mounted on a vehicle body, a motor that rotates the wheels using power supplied from a battery, and a grip portion that detects the operating force applied by a user, performs a process including: a drive control step of controlling the drive of the motor to perform assist control corresponding to at least the operating force of the grip portion, wherein in the drive control step, if there is a loss of power from the battery, the drive of the motor is controlled by regenerative power generated from the motor by the rotation of the wheels, thereby enabling the execution of the assist control.

13. A program that causes a computer to function as a control device for controlling an electric vehicle comprising wheels mounted on a vehicle body, a motor that rotates the wheels using power supplied from a battery, and a grip portion that detects the operating force applied by a user, wherein the computer functions as a drive control means that controls the drive of the motor and performs assist control corresponding to at least the operating force of the grip portion, and the drive control means is capable of performing the assist control by controlling the drive of the motor with regenerative power generated from the motor by the rotation of the wheels in the event of a power loss from the battery.

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