A takeoff location and a landing location are received for an autonomous vertical takeoff and landing (VTOL) vehicle that includes a plurality of rotors. An autonomous and noise-reduced flight trajectory for the autonomous VTOL vehicle is determined based at least in part on the takeoff location, the landing location, a jerk function, and a noise function, including by minimizing the jerk function and minimizing the noise function. A set of one or more desired forces or moments is determined for the autonomous VTOL vehicle based at least in part on autonomous and noise-reduced flight trajectory. A plurality of motor control signals is determined for the plurality of rotors based at least in part on the set of one or more desired forces or moments.

A new method and circuit arrangement for operating a stepper motor in a voltage-based operating mode with a control loop over the whole operating range of speeds of a stepper motor. The method/circuit arrangement includes calculating a load angle of the stepper motor. The load angle is then used to calculate a voltage-based control signal suitable for operating a known motor driver circuit, such as a chopper, to drive the stepper motor coils. This enables improved control over the stepper motor which can improve control stability.

Various embodiments related to hydraulic actuators and active suspension systems as well as their methods of use are described.

As described herein, a drive circuit for a three phase AC motor comprises an AC/AC converter. The converter has an input for receiving multiphase AC power from an AC source and converting the AC power to variable voltage and variable frequency from the AC source for driving the AC motor. A filter circuit is connected to the AC/AC converter and comprises at least one inductor per phase and at least one capacitor per phase. The capacitors are connected in a broken wye configuration with one side connected to one of the inductors and an opposite side connected via a three phase diode bridge rectifier to a switch. The switch is controlled by a converter control to selectively open or short a neutral point of the broken wye capacitor configuration.

As described herein, a drive circuit for a three phase AC motor comprises an AC/AC converter. The converter has an input for receiving multiphase AC power from an AC source and converting the AC power to variable voltage and variable frequency from the AC source for driving the AC motor. A filter circuit is connected to the AC/AC converter and comprises at least one inductor per phase and at least one capacitor per phase. The capacitors are connected in a broken wye configuration with one side connected to one of the inductors and an opposite side connected via a three phase diode bridge rectifier to a switch. The switch is controlled by a converter control to selectively open or short a neutral point of the broken wye capacitor configuration.

Various embodiments related to hydraulic actuators and active suspension systems as well as their methods of use are described.

A method and system for reducing rollback in a counterbalancing system as a holding brake is released is disclosed. A limited amount of movement of a drive shaft is present in the holding brake. A motor drive provides current to the motor with the holding brake set such that a torque is applied at the drive shaft. The current is controlled to generate torque in both directions. The limited amount of movement in the brake may be used to determine a direction and magnitude of torque required to support a mechanical load being applied to the motor. The motor drive then provides a current to generate the necessary torque required to support the load prior to releasing the holding brake.

A windshield wiper system includes a three-phase motor, the three-phase inverter, a brake circuit, and a controller. The controller transmits commutation signals to the three-phase inverter to drive the motor according to an inboard-to-outboard speed profile and to drive the motor according to an outboard-to-inboard speed profile. The controller activates the brake circuit based on the inboard-to outboard speed profile, or the outboard-to-inboard speed profile, and a direct current bus voltage.

A control method is applied to a hybrid power system including an engine and a motor. A motor stator of the motor is connected to a driving shaft of a motor vehicle by means of a transmission mechanism such that, when rotated, the driving shaft drives the motor stator to rotate; the motor is used to determine output torque according to the rotating speed of the motor and transmit same to the driving shaft; the rotating speed of the motor is equal to the difference between the rotating speed of the motor rotor and the rotating speed of the motor stator. The method includes, according to operating parameters of the hybrid power system and operating parameters of the motor vehicle, controlling a motor controller to provide a drive signal to the motor stator such that the operating parameters of the motor meet a first preset formula.

A control method is applied to a hybrid power system including an engine and a motor. A motor stator of the motor is connected to a driving shaft of a motor vehicle by means of a transmission mechanism such that, when rotated, the driving shaft drives the motor stator to rotate; the motor is used to determine output torque according to the rotating speed of the motor and transmit same to the driving shaft; the rotating speed of the motor is equal to the difference between the rotating speed of the motor rotor and the rotating speed of the motor stator. The method includes, according to operating parameters of the hybrid power system and operating parameters of the motor vehicle, controlling a motor controller to provide a drive signal to the motor stator such that the operating parameters of the motor meet a first preset formula.