A controller and related system and method for controlling a choke for choking fluid flow are configured to take into account non-linear behaviors of the choke, to allow more accurate and effective control of the choke. To obtain a desired pressure drop across a choke valve, the controller is configured to monitor the position of a choke actuator coupled to the choke valve and the pressure at the inlet of the choke valve. The controller calculates an adaptive proportional gain coefficient, and optionally adaptive integral and derivative coefficients, based on the choke actuator position, to help mitigate the effects of non-linear behaviors of the choke and, where necessary, based on the inlet pressure, the controller calculates an augmentation correction to address any instability in the choke. The controller then commands the choke actuator accordingly to adjust the flow area through the choke valve.

A system and method of storing and reading digital data, including providing a nanopore polymer memory (NPM) device having at least one memory cell comprising at least two addition chambers each arranged to add a unique chemical construct (or codes) to a polymer (or DNA) string when the polymer enters the respective addition chamber, the data comprising a series of codes; successively steering the polymer from deblock chambers through the nanopore into the addition chambers to add codes to the polymer to create the digital data pattern on the polymer; and accurately controlling the bit rate of the polymer using a servo controller. The device may have loading chamber(s) to load (or remove) the polymer into/from the deblock chambers through at least one “micro-hole”. The cell may be part of a memory system that stores and retrieves “raw” data and allows for remote retrieval and conversion. The cell may store multi-bit data having a plurality of states for the codes.

A system and method of storing and reading digital data, including providing a nanopore polymer memory (NPM) device having at least one memory cell comprising at least two addition chambers each arranged to add a unique chemical construct (or codes) to a polymer (or DNA) string when the polymer enters the respective addition chamber, the data comprising a series of codes; successively steering the polymer from deblock chambers through the nanopore into the addition chambers to add codes to the polymer to create the digital data pattern on the polymer; and accurately controlling the bit rate of the polymer using a servo controller. The device may have loading chamber(s) to load (or remove) the polymer into/from the deblock chambers through at least one “micro-hole”. The cell may be part of a memory system that stores and retrieves “raw” data and allows for remote retrieval and conversion. The cell may store multi-bit data having a plurality of states for the codes.

A synchronous machine includes a stator with stator windings connected with stator terminals to an electrical grid and a rotor with rotor windings rotatable mounted in the stator, wherein a voltage regulator of the synchronous machine is adapted for outputting an excitation signal to adjust a current in the rotor windings for controlling the synchronous machine. A method for determining control parameters for the voltage regulator includes (i) receiving a first time series of values of the excitation signal and a second time series of measurement values of the terminal voltage in the stator terminals, (ii) determining coefficients of a system transfer function of the synchronous machine, and (iii) determining the control parameters for the voltage regulator from the coefficients of the system transfer function.

A controller of a shock absorber has a differential path configured to perform derivative compensation on the basis of a difference between a target pressure and a detected pressure or on the basis of the detected pressure, multiply the compensated value by a negative gain, and output a resulting value of the multiplication, and obtains an electric current instruction applied to a pressure control solenoid valve.

A prosthetic or orthotic device has an elongate frame that houses electronics and an actuator rotatably mounted to the frame. The actuator can rotate in an anterior-posterior direction about a medial-lateral axis and includes magnetorheological (MR) fluid and a coil operable to selectively apply a magnetic field to the MR fluid to vary its viscosity and thereby vary a torsional resistance of the actuator about the medial-lateral axis. Circuitry controls an amplitude of a current applied to the coil, and employs a gains schedule to accelerate a change in the current amplitude based on an error amplitude between a current set point and a measured current to reduce a response time for varying the torsional resistance of the actuator.

A prosthetic or orthotic device has an elongate frame that houses electronics and an actuator rotatably mounted to the frame. The actuator can rotate in an anterior-posterior direction about a medial-lateral axis and includes magnetorheological (MR) fluid and a coil operable to selectively apply a magnetic field to the MR fluid to vary its viscosity and thereby vary a torsional resistance of the actuator about the medial-lateral axis. Circuitry controls an amplitude of a current applied to the coil, and employs a gains schedule to accelerate a change in the current amplitude based on an error amplitude between a current set point and a measured current to reduce a response time for varying the torsional resistance of the actuator.

The invention relates to a hydraulic actuator (1) that can be controlled by a main valve (2) and an auxiliary valve (3). Upstream of the main valve device (2) is a main regulator (7), having a P block (9) and an I block (10). Upstream of the auxiliary valve (3) is an auxiliary regulator (8), having a base block (11) and an I block (12). In a normal mode of operation, the auxiliary valve (3) is deactivated. The main regulator is provided with a main setpoint variable (p*) and a corresponding main actual quantity (p) of the hydraulic actuator (1). The main regulator (7) determines a main actuating variable (s) and predefines the main actuating variable (s) in the main valve device (2). In a special mode of operation, the base block (11) of the auxiliary regulator (8) is provided with an auxiliary setpoint variable (a*) and a corresponding auxiliary actual quantity (p) of the hydraulic actuator (1). The base block (11) of the auxiliary regulator (8) determines an auxiliary actuating variable (s′) and predefines the auxiliary actuating variable (s′) in the auxiliary valve device (3). The I block (12) of the auxiliary regulator (8) is provided with the main setpoint variable (p*) and the main actual quantity (p). The I block (12) of the auxiliary regulator (8) determines an integral component (si′) therefrom. The integral component (si′) is applied to the auxiliary actuating variable (s′). In the special mode of operation, the P block (9) is provided with the main setpoint variable (p*) and the main actual quantity (p). In the special mode of operation, the P-block (9) determines the main actuating variable (s) and predefines the main actuating variable (s) in the main valve device (2).

The invention relates to a hydraulic actuator (1) that can be controlled by a main valve (2) and an auxiliary valve (3). Upstream of the main valve device (2) is a main regulator (7), having a P block (9) and an I block (10). Upstream of the auxiliary valve (3) is an auxiliary regulator (8), having a base block (11) and an I block (12). In a normal mode of operation, the auxiliary valve (3) is deactivated. The main regulator is provided with a main setpoint variable (p*) and a corresponding main actual quantity (p) of the hydraulic actuator (1). The main regulator (7) determines a main actuating variable (s) and predefines the main actuating variable (s) in the main valve device (2). In a special mode of operation, the base block (11) of the auxiliary regulator (8) is provided with an auxiliary setpoint variable (a*) and a corresponding auxiliary actual quantity (p) of the hydraulic actuator (1). The base block (11) of the auxiliary regulator (8) determines an auxiliary actuating variable (s′) and predefines the auxiliary actuating variable (s′) in the auxiliary valve device (3). The I block (12) of the auxiliary regulator (8) is provided with the main setpoint variable (p*) and the main actual quantity (p). The I block (12) of the auxiliary regulator (8) determines an integral component (si′) therefrom. The integral component (si′) is applied to the auxiliary actuating variable (s′). In the special mode of operation, the P block (9) is provided with the main setpoint variable (p*) and the main actual quantity (p). In the special mode of operation, the P-block (9) determines the main actuating variable (s) and predefines the main actuating variable (s) in the main valve device (2).

While an aircraft is mid-flight, a braking start point associated with a stoppable rotor is calculated where the stoppable rotor includes a first and second blade and the stoppable rotor is configured to rotate about a substantially vertical axis. A process to stop the stoppable rotor is started, while the aircraft is mid-flight, when the stoppable rotor reaches the braking start point, where the stoppable rotor is stopped with the first blade pointing forward and the second blade pointing backward.