12results about How to "Smooth speed change" patented technology

The invention provides a speed look-ahead method for a spindle of a rotary template sewing machine and related equipment, and the method comprises the following steps: determining a shortest sewing period, and determining a minimum rotation angle of continuous movement of a rotating shaft according to the period; the track curvature of each stitch is determined, for the stitch with the track curvature larger than the minimum rotation angle of continuous movement, the spindle limiting speed of the stitch is determined according to the rotation axis movement time corresponding to the stitch, and for the stitch with the track curvature not larger than the minimum rotation angle of continuous movement, the spindle limiting speed of the stitch is determined according to the shortest sewing period; determining the spindle limiting speed of the stitch; and based on the spindle limiting speed of each stitch, performing spindle speed look-ahead planning on each stitch through a backtracking method to obtain a spindle planning speed of each stitch. By applying the method provided by the invention, the speed of the main shaft can be forecasted by combining the constraints of feeding movement and rotation shaft movement, the planning speed of the main shaft which changes smoothly and meets the corresponding movement constraints can be obtained, and the sewing stability can be improved.

The application improves a variable frequency fan natural wind simulation method based on algorithm control, solves the problems of current variable frequency fan natural wind simulation, such as non-complete randomness, existence of partial periodicity and still predictable, large random error, and thus reduces user experience, the method comprises the following steps: determining a natural wind basic wind speed; selecting a certain segment of simulated natural wind duration length; selecting a pulse wind speed reference value, calculating a pulse wind speed; judging and calculating the simulated natural wind speed in this segment of time; judging whether to return to the step according to the relationship between the control duration and the selected simulated natural wind duration, the application uses a single-chip microcomputer to control the fan speed, uses an algorithm to simulate the natural wind, changes the fan speed through continuous circulation and reciprocation to realize the simulation of the natural wind, simultaneously applies a first-order low-pass filter, the speed change is more smooth, and the service life of the machine body is also protected, and the application has the advantages of intelligence, high efficiency, and strengthened user comfort, etc.

The application discloses a model-based mode switching combined control method for a shaft fan variable cycle engine. Firstly, a constant rotating speed control is carried out on a low-pressure output shaft of an external rotor, a low-pressure rotor rotating speed cascade controller is designed, and parameters of the cascade controller in the mode switching process are on-line set through a fuzzy theory. Secondly, through analysis of the relationship between the residual power of the low-pressure shaft and the rotating difference and the compressor surge margin in the mode switching process, a closed-loop controller for an internal connotation nozzle area is designed to compensate the output power of the low-pressure shaft and reduce the engine thrust; in order to inhibit the disturbance caused by the clutch engagement / disengagement and the pitch angle change in the mode switching process, a nozzle area pre-opening strategy and a pitch angle feedforward are introduced, and the surge margin of the low-pressure compressor in the mode switching process is improved through bleeding regulation. The application can provide a technical reference for the engineering development of a new generation of high-speed long-range helicopter power device in China.

The invention discloses a humanoid tea bud picker, which relates to the technical field of tea leaf picking devices and comprises a clamping mechanism, a rotating mechanism, a tea bud collecting box and a motor damping system. The rear end of the clamping mechanism is provided with a 42 stepping motor, the front end of the motor is provided with a pair of gears with the tooth number ratio being 1: 2, the front end of the gear set is provided with a lead screw and a sliding block nut, the most front end of the clamping mechanism is provided with clamping fingers, the middle of the clamping fingers is provided with a picking blade, and the inner sides of the clamping fingers are pasted with flexible material sponges. The picker support is connected with the clamping fingers through the clamping finger arms and the external connecting pieces. The rotating mechanism is located below the clamping mechanism, and the tea bud collecting box is located at the rear end of the rotating mechanism. According to the humanoid tea bud picker, by simulating the action of pinching and rotating the wrist when the tea buds are manually picked, the integrity rate and picking efficiency of the tea buds are improved, and famous and high-quality tea is picked.

The invention discloses a crane safety early warning method based on data driving and application thereof.According to the scheme, a public area in a working site of a tower crane is monitored in real time, so that a dynamic object in the site can be monitored, and when a lifting appliance assembly of the subsequent crane transfers an object, the safety early warning of the crane is achieved. Data guarantee is provided for efficient and comprehensive field monitoring; according to the early warning mechanism, under the condition that the position information of the lifting appliance assembly, the carrier and the worker in the working site is monitored in real time, the prediction position of a certain time step length is established, certain position pre-judgment is provided for the lifting appliance assembly when the to-be-transferred object is transferred, and the accuracy of the to-be-transferred object is improved. And movement interference or other risk problems between the lifting appliance assembly or the transferred object and a carrier and a worker in a working site are avoided. According to the scheme, PID is further used for adjusting the speed change, so that the speed change is more stable when the moving speed of the lifting appliance assembly is adjusted; and the control stability of components of the crane is improved.

The utility model discloses a large-scale articulated bus road energy harvesting system, relates to the technical field of energy collection, and aims to solve the technical problem that a road energy harvesting system using vehicle vibration energy is urgently required to be developed in the prior art to generate power and supply power to road sensing equipment. The system comprises an input module, a conversion module and a power generation module which are connected in sequence. The input module comprises a fixing frame connected with a guide mechanism, the guide mechanism makes contact with a vehicle and receives vibration of the vehicle, an elastic energy storage device arranged between the fixing frame and the guide mechanism is arranged on the guide mechanism, and the guide mechanism is connected with the conversion module through a first connecting device. The conversion module comprises a rotating mechanism, the rotating mechanism converts linear motion of the guide mechanism into rotating motion, and the rotating mechanism is connected with a power generation module which performs electromagnetic induction power generation through rotation. The input module, the conversion module and the like are adopted, mechanical energy of vehicle vibration is converted into electric energy, energy is effectively converted and utilized, and energy conversion and utilization efficiency is improved.

The application discloses a kind of based on improved model predictive control unmanned ship trajectory tracking control method and device.The method includes, H-PINN method is introduced into unmanned ship hydrodynamics model, obtains the simplified hydrodynamics model of unmanned ship;Based on the prediction model of the trajectory tracking of unmanned ship obtained in simplified hydrodynamics model, the expected trajectory and control quantity of model predictive control MPC are designed using differential flatness theory, and stability analysis is designed according to Lyapunov function.The method improves model predictive control using differential flatness theory, and Lyapunov function optimization analysis is combined, improves trajectory tracking precision, reduces the change amplitude of control quantity, so that the speed change in navigation process is more smooth.

A control method for slow variable-power start-up of a scraper conveyor includes: controlling the start-up of the motors at the head and tail of the scraper conveyor in four stages: In the first stage, the conveyor starts from zero speed and accelerates uniformly until the output torque of the head motor reaches a first torque threshold, at which point it enters the second stage; in the second stage, the conveyor moves at a uniform speed at the speed at which it entered the second stage, until the chain tension reaches a tension threshold, at which point it enters the third stage; in the third stage, the conveyor uses the speed at which it entered the third stage as the initial speed, gradually increasing acceleration, and then gradually decreasing acceleration until the output torque of the head motor reaches a second torque threshold, at which point it enters the fourth stage; and in the fourth stage, the conveyor moves at a uniform speed at the speed at which it entered the fourth stage. This method can reduce the number of chain tension peaks and the vibration frequency.

This utility model discloses an optimization device for an automatic reciprocating control system of a high-speed wire rod winding trolley, belonging to the field of high-speed wire rod production technology. This optimization device includes a support assembly, a mobile trolley body, a control cabinet, and a heat dissipation mechanism. The control cabinet houses the control system body. The heat dissipation mechanism includes a mounting box, the front of which is fixedly connected to the back of the control cabinet. A partition is installed inside the mounting box, and the front of the partition and the inner wall of the mounting box form a storage cavity filled with coolant. Several first heat dissipation fins are installed on the front of the mounting box, extending through the control cabinet into the interior at the end furthest from the mounting box, and extending through the mounting box into the water storage cavity at the other end furthest from the control cabinet. This utility model effectively optimizes heat dissipation and has high practical value.

The utility model relates to a product turnover carrying mechanism, including base, vertical drive component, bearing frame and two turnover subassembly, and turnover subassembly includes drive motor, transmission mechanism and adsorption component, and drive motor rotates adsorption component through transmission mechanism, bearing frame includes the mounting panel connected with the output end of vertical drive component, and first vertical plate and second vertical plate are connected respectively in the both sides of mounting panel, and one turnover subassembly is installed on first vertical plate or second vertical plate respectively, and the relief hole is set up on first vertical plate or second vertical plate, and one of two turnover subassembly, its adsorption component is worn in the relief hole, makes the adsorption component of two turnover subassembly to the same direction and presents high and low arrangement, the utility model discloses adopt the integrated design concept, through the clever relief structure of sharing bearing frame, makes two turnover subassembly in the limited space cooperation work, effectively solved the equipment layout limited problem of traditional mechanism because of the structure redundancy.