41results about How to "Guaranteed dynamic stability" patented technology

An earthmoving machine including a control system is disclosed. The machine comprises first and second satellite navigation antennas mounted in a longitudinal direction on the earthmoving machine. A third satellite navigation antenna is mounted on a pole attached to an operational element of the earthmoving machine. In one embodiment, the earthmoving machine is a bulldozer and the operational element is a blade of the bulldozer. The machine further comprises a gravity reference sensor and a plurality of gyroscopes mounted on the machine. A computer processor generates control signals based on sensor data received from the various components. The disclosed system and method allows for dynamically stable operation of the earthmoving machine at relatively fast speeds without the development of unwanted oscillations.

The invention discloses a compound for the stress absorbing layer of rubber asphalt and a preparation method and application thereof. In the invention, the method for preparing the compound for the stress absorbing layer of the rubber asphalt comprises the following steps: adding 17-20 parts of radial tyre rubber powder by weight, 2-6 parts of rubber processing oil by weight and 0.1-0.3 part of montmorillonite by weight into 75-80 parts of road petroleum asphalt, stirring and reacting for 45-120min at the temperature of 180-200 DEG C to obtain the rubber asphalt; heating 100 parts of mineral aggregate by weight to 160-200 DEG C, adding 9-11 parts of rubber asphalt by weight, and evenly stirring to obtain the finished product of the compound for the stress absorbing layer of the rubber asphalt. The compound for the stress absorbing layer of the rubber asphalt, which is prepared according to the method of the invention, is specially used as an intermediate layer when asphalt pavement is coated on the cement pavement, thus playing the role of preventing reflection cracks.

The invention discloses a self-adaptive robust control method and device for an under-actuated hydraulic single-leg power-assisted exoskeleton. The control method comprises the following steps of establishing a physical model; obtaining a reference displacement and an actual displacement; adopting the actual displacement and the reference displacement as input quantities, and adopting the output of a middle-layer position tracking controller as a virtual expected joint driving torque; and converting the expected joint torque into expected hydraulic cylinder output force, adopting the expected hydraulic cylinder output force and actual hydraulic cylinder output force as input quantities, converting flow into driving voltage of an electro-hydraulic servo valve, using the driving voltage to control the output force of a hydraulic cylinder, and driving all joints of the under-actuated single-leg power-assisted exoskeleton to rotate. According to the self-adaptive robust control method and device for the under-actuated hydraulic single-leg power-assisted exoskeleton provided by the invention, under the condition that the number of the hydraulic cylinders is smaller than the number of freedom degrees of motion of the exoskeleton, the influences of multi-joint strong coupling of the under-actuated hydraulic single-leg power-assisted exoskeleton, high-order nonlinearity of a hydraulic driver and model uncertainty are effectively overcome, and the good following and power-assisted effects of the hydraulic power-assisted exoskeleton on human motion are achieved.

The invention discloses a combined steel box girder and a construction method thereof, belonging to the field of high-speed railway bridges. A steel box of the combined steel box girder comprises adjacent upper steel box and a lower steel box sharing one horizontal separating plate; a prefabricated prestressed concrete plate is glued to the inner of the lower steel box with structural glue. The prestressed concrete plate passes through the lower steel box and the peripheral gap is filled with structural glue. Since the girder is made of the steel box, a concrete top board and the prestressed concrete plate inside the lower steel box, the girder can be assembled on site, which is convenient for transportation and hoisting for construction and it is possible to build simply supported beams with larger span. Compared with present whole simple girders of the same span, the provided combined steel box girder has increased cross section rigidity of the steel box girder, the weight of girders is reduced and the span of girders is increased. The combined steel box girder of the invention has reasonable construction stress and is convenient to construct; the method is applied for building high speed railway beam bridges with larger span.

The invention discloses a self-adaptive three-step method-based truck formation driving following vehicle control method. A vehicle longitudinal dynamics equation is established according to a stresssituation of a vehicle in a running process; by using the vehicle longitudinal dynamics equation, taking expected vehicle distance deviation and speed deviation as state variables, and taking an expected output torque as a control variable, establishing a nonlinear state space equation; then establishing queue integral Lyapunov, and then based on this, establishing a form of a controller referenceinput signal; and based on a three-step method control theory, designing a controller, determining a parameter self-adaptation law of the three-step method controller, obtaining a control rate of thecontroller, determining an output control variable by the controller according to state information at each moment and in combination with an expression form of a control law, and applying the outputcontrol variable directly serving as a driving/braking torque signal to the controlled vehicle. A Lyapunov function method is used in a design process of a controller reference input, and the three-step method controller is used for adjusting the parameters of the controller in real time under the adjustment of the self-adaptive law.

The invention relates to a method for planning and tracking a local obstacle avoidance path of an autonomous vehicle. The method comprises the following steps: acquiring a global reference path; planning a local path of the autonomous vehicle through an RRT local path planner; and stably and effectively tracking an ideal local obstacle avoidance path by adopting a personified T-S fuzzy path tracking strategy. According to the invention, a vehicle dynamics model is fused into an RRT algorithm, and the personified driver behavior dynamics model and the fuzzy algorithm are fused in path tracking control so that the autonomous vehicle can effectively track an ideal obstacle avoidance path in a high-dynamic road environment, and meanwhile, the dynamics stability of the vehicle can be well ensured; and a theoretical basis preparation is made for path planning and tracking of the autonomous vehicle applied to urban road vehicle driving with dense pedestrians, field environment engineering vehicle obstacle avoidance driving and even battlefield military vehicle actual obstacle avoidance driving for avoiding enemy firepower in the future.

The invention provides a method for designing a multi-balance point nonlinear system for dynamic stability control. The method comprises the following steps of: 1) establishing a synchronous unit model, and determining a gradient-like definition; 2) judging the gradient-like performance of the synchronous unit model, and if the synchronous unit model is chaotic, executing the step 3); 3) performing controller design on the synchronous unit model in the step 1); and 4) performing dynamic stability analysis and control on a power system by using a controller in the step 3), so the dynamic stability of the whole power system is ensured. According to a dynamic stability control method which is employed in the invention, the linearization of the conventional like methods is eliminated, so accumulated errors which are generated in the method are greatly reduced, and a future practical engineering guiding function is realized.

The invention discloses a method for simultaneously identifying loads and mutual inductance of a multi-load wireless power transmission system, which comprises the following steps of: firstly, enabling a multi-load system to be equivalent to single-load systems with different working time sequences through a time division multiplexing method; voltage overshoot and instable voltage occurring in a time division operation identification algorithm are prevented through double filter capacitors and bus voltage adjustment; and then introducing a particle swarm algorithm, establishing a system steady-state circuit model, establishing a fitness function through a difference value between a sampling output voltage and a prediction output voltage, converting a parameter identification problem into an algorithm optimization problem, and carrying out optimal solution search on a to-be-identified parameter to replace a traditional calculation method, so that errors generated by a traditional equation are avoided. According to the method, only input and output voltages need to be sampled, the communication data volume is reduced, the circuit complexity is reduced, and the system size is reduced. According to the method, the load and mutual inductance of the multi-load wireless charging system can be identified in real time, and the working range of the wireless charging system is expanded.

The invention discloses a preparation method of a surface abrasion-resistant coating of a floating clamping jaw of a numerical control punching machine. Firstly, chromium oxide ceramic particles and alow-melting-point additive are weighed according to the proportion of the coating and are evenly mixed; and then the high-performance abrasion-resistant coating is prepared on the surface of the clamping jaw after sand blasting through an atmospheric plasma spraying technology. The method solves the problem that a dovetail groove structure is used in a traditional floating clamping jaw of the numerical control punching machine and accordingly a plate is locally deformed in the clamping process. The low-melting-point glass powder additive in the mixed powder is of a unique spherical structure,so that the fluidity is better, the repose angle formed due to stacking is smaller, and material mixing is more uniform; a base material and a filler can be sufficiently dense, the density of the prepared coating is greatly improved, and problems of the pure chromium oxide coating in the using process are effectively solved, so that the tribology performance of the coating is better, the servicelife is longer, and the preparation cost is lower; and the thermal influence of the spraying process on the floating clamping jaw of the numerical control punching machine is small, and the structureand shape of a base body are not changed.

The invention provides a 3d (three-dimensional) visual movable composite robot. Four wheels of the movable robot are respectively connected to a body of the movable robot through a telescopic rod, a motor drives the four wheels to rotate, a radar detector is used for detecting barriers with a certain distances away from the front and the rear of the movable robot and acquiring distance data among the movable robot and the barriers, a gyroscope is used for acquiring inclination angles of the movable robot, a GPS (global positioning system) positioning module is used for acquiring position data of the movable robot, a control module is used for controlling the telescopic rods of the four wheels to expand and contract, a stepping motor controls the telescopic rods to expand and contract, a hand-held control terminal is used for transmitting instructions to the control module, and the control module controls the telescopic rods of the four wheels of the movable robot and the motor. The 3d visual movable composite robot can effectively control postures and directions of the robot, and dynamic stability of the robot is ensured.

The invention provides an iterative local search method for solving a power grid splitting problem. The iterative local search method is mainly used for solving an island problem of a power system, and mainly comprises three parts, namely a two-stage method, a local search method and a disturbance method. The two-stage method is used for randomly generating a feasible initial solution; the local search method is used for improving an existing solution; and the disturbance method is used for jumping out of a local optimum trap. According to the iterative local search method, after the feasibleinitial solution is generated, local search and disturbance optimization are continuously executed on the current solution until the deadline is up, and the algorithm is ended. Under the condition that connectivity constraints of power grid islands, generator coherence constraints and power transmission capacity constraints are met, power grid splitting of thousands of power nodes can be achievedin a short time, and the defect that an existing algorithm can only be used for a small-scale power grid is overcome to a certain extent. The iterative local search method has the advantages of high calculation speed, high solving quality and practicability, and can solve the island problem of the power system effectively.

The invention discloses a self-adaptive robust force control method and device for an under-actuated supporting leg assisting exoskeleton. The control method comprises the steps that a physical modelis established and converted into a state equation, wherein the physical model comprises a man-machine interface model, a motion model and a complete constraint model; the reference displacement of the under-actuated supporting leg assisting exoskeleton is obtained; the actual angle value of the exoskeleton and the actual displacement of the back contact portion are obtained; the actual displacement and the reference displacement are taken as input quantities, and the output of a lower-layer position tracking controller is taken as motor driving torque; and the motor driving torque is converted into output torque of control current control motors, and all joints of the under-actuated supporting leg assisting exoskeleton are driven to rotate. Under the condition that the number of the motors is smaller than the number of freedom degrees of exoskeleton movement, the influence of multi-joint strong coupling and model uncertainty of the under-actuated supporting leg assisting exoskeleton is effectively overcome, the good following and assisting effect of the assisting exoskeleton on human movement is achieved, and high application value is achieved.

The invention relates to a robust control method and device for an under-actuated double-leg supporting hydraulic power-assisted exoskeleton. The control method comprises the following steps: initializing a sampling period of the real-time controller; the motion states of the left leg foot and the right leg foot of the exoskeleton are judged; establishing a physical model of the exoskeleton and converting the physical model into a state equation; the back acting force is obtained, and reference displacement is obtained in an upper-layer controller; an expected driving torque is obtained in a middle-layer controller according to the reference displacement; the expected flow of the electro-hydraulic servo valve is obtained in a lower-layer controller according to the expected driving torque; generating a current signal according to the expected flow; according to the current signals, all joints of the exoskeleton are driven to rotate, and tracking motion of the exoskeleton is achieved. The human-computer interaction exoskeleton following motion model is established by integrating multiple factors, the closed-chain dynamics problem of the exoskeleton is effectively solved, the influence of various interferences and uncertainties on the exoskeleton following motion is eliminated to a great extent, and the robustness of exoskeleton control is enhanced.