Vibrational notification of motor conditions in a self-balancing electric vehicle
A method for vibrationally notifying a rider of a self-balancing electric vehicle may include: operating a self-balancing electric vehicle, receiving, at a motor controller of a self-balancing electric vehicle, a measured value corresponding to a first parameter of the self-balancing electric vehicle, and applying a first pattern of vibrational impulses to a motor of the self-balancing electric vehicle in response to the self-balancing electric vehicle satisfying a first operational threshold value.
1 . A method for vibrationally notifying a rider of a self-balancing electric vehicle, the method comprising:
operating the self-balancing electric vehicle;
receiving, at a motor controller of the self-balancing electric vehicle, a measured value corresponding to a first parameter of the self-balancing electric vehicle;
operating a motor of the self-balancing electric vehicle to rotate a ground-contacting element of the self-balancing electric vehicle and propel the self-balancing electric vehicle; and
in response to the self-balancing electric vehicle satisfying a first operational threshold value, generating a vibrational notification by applying, using the motor controller, a first pattern of vibrational impulses to the motor by sequentially increasing and decreasing a quadrature voltage applied to the motor,
wherein increasing and decreasing the quadrature voltage applied to the motor includes applying a positive square wave impulse followed by a negative square wave impulse, and wherein the first pattern of vibrational impulses are configured to avoid disturbing current and torque regulation of the self-balancing electric vehicle, wherein the first pattern of vibrational impulses are added to the quadrature voltage after the torque regulation performed by a torque controller.
2 . The method of claim 1 , further comprising continually applying the first pattern of vibrational impulses until the measured value no longer satisfies the first operational threshold value.
3 . The method of claim 1 , further comprising applying a second pattern of vibrational impulses to the motor of the self-balancing electric vehicle in response to the measured value satisfying a second operational threshold value.
4 . The method of claim 3 , wherein the first operational threshold value and the second operational threshold value define endpoints of a warning range.
5 . The method of claim 3 , wherein the second pattern of vibrational impulses is different than the first pattern of vibrational impulses.
6 . The method of claim 5 , further comprising continually applying the second pattern of vibrational impulses until the measured value no longer satisfies the second operational threshold value.
7 . The method of claim 1 , wherein the first parameter is a speed of the self-balancing electric vehicle, wherein the measured value is a measured speed of the self-balancing electric vehicle, and wherein the first operational threshold value is a selected warning speed of the self-balancing electric vehicle.
8 . The method of claim 1 , wherein the first parameter is a torque of the self-balancing electric vehicle, wherein the measured value is a torque of the motor, and wherein the first operational threshold value is a selected warning torque.
9 . A vibrational notification system for a self-balancing electric vehicle, the system comprising:
a motor configured to rotate a ground-contacting element of the self-balancing electric vehicle and propel the self-balancing electric vehicle; and
a motor controller configured to drive the motor and comprising a field-oriented control module including a vibration controller configured to send vibrational impulses to the motor while the motor is driving the ground-contacting element;
wherein the vibrational impulses comprise increases and decreases in a quadrature voltage applied to the motor, wherein the vibrational impulses are added to the quadrature voltage after torque regulation performed by a torque controller.
10 . The vibrational notification system of claim 9 , wherein the vibrational impulses have a frequency configured to excite a mechanical resonant frequency of a frame of the self-balancing electric vehicle.
11 . The vibrational notification system of claim 9 , wherein the vibration controller is configured to send the vibrational impulses to the motor in response to a measured vehicle speed satisfying a threshold speed.
12 . The vibrational notification system of claim 9 , wherein the increases and decreases in the quadrature voltage applied to the motor comprise positive square wave impulses and negative square wave impulses, respectively.
13 . The vibrational notification system of claim 9 , further comprising a power supply management system coupled to the vibration controller, wherein the power supply management system is configured to send a state of charge of a battery of the self-balancing electric vehicle to the vibration controller.
14 . The vibrational notification system of claim 13 , wherein the vibration controller is configured to send the vibrational impulses to the motor in response to the state of charge satisfying a threshold charge.
15 . The vibrational notification system of claim 9 , wherein the vibration controller receives an estimated speed value, and the vibration controller applies the vibrational impulses to the quadrature voltage based on the estimated speed value.
16 . A self-balancing electric vehicle comprising:
a wheel having an axis of rotation;
a board including a frame having an aperture to accommodate the wheel, such that the board is tiltable about the wheel, first and second deck portions of the board each configured to receive a left or right foot of a rider oriented generally perpendicular to a direction of travel of the board;
an electric hub motor configured to drive the wheel; and
a motor controller configured to drive the electric hub motor and comprising a field-oriented control module including a vibration controller configured to send vibrational impulses to the electric hub motor while driving the electric hub motor;
wherein sending the vibrational impulses comprises increasing and decreasing a quadrature voltage applied to the electric hub motor, wherein the vibrational impulses are added to the quadrature voltage after torque regulation performed by a torque controller.
17 . The self-balancing electric vehicle of claim 16 , further comprising a speed estimator circuit configured to send a measured speed of the self-balancing electric vehicle to the vibration controller.
18 . The self-balancing electric vehicle of claim 17 , wherein the vibration controller is configured to send the vibrational impulses to the electric hub motor in response to the measured speed satisfying a threshold speed.
19 . The self-balancing electric vehicle of claim 16 , wherein the increases and decreases in the quadrature voltage applied to the electric hub motor comprise positive and negative square wave impulses.
20 . The self-balancing electric vehicle of claim 16 , wherein the vibrational impulses have a frequency configured to excite a mechanical resonant frequency of the frame.