87 results about "High-altitude wind power" patented technology

The invention discloses a series bidirectional driven wind power system. The system comprises two winches, two umbrella-type wind power devices and a central control device, wherein the two winches are connected to two ends of a transmission shaft of a working device respectively; the two umbrella-type wind power devices are used for collecting wind energy at high altitude, converting the wind energy into mechanical energy and outputting the mechanical energy through working ropes respectively, and the working ropes are connected to winding drums of the two winches by winding in the same winding direction; and the central control device is connected with and controls the two umbrella-type wind power devices and the two winches, and the central control device is used for controlling the umbrella-type wind power devices to asynchronously stop in declining stages in each working period and stop outputting the mechanical energy. Compared with a single umbrella-type wind power system, the series bidirectional driven wind power system has the advantage that: continuity and stability of energy output of the high-altitude wind power system are greatly improved.

The invention discloses a high altitude wind power generator, comprising an airbag with levitating force, a rope for fixing the airbag, a generator and a reversing winch on the ground, and an operation control system, wherein, one end of the rope for fixing the airbag is fixed on the geometric center of the airbag, while the other end is wound on a rotor of the generator or on a transmission device connected with the rotor; and the airbag is of a flat shape and has an adjustable windward angle. The high altitude wind power generator has the following operating processes that: the operation control system adjusts the windward angle of the airbag to ensure that the front of the airbag faces towards wind, the airbag moves along the wind direction from the initial position under the action of wind power and draws the rotor to rotate and generate electricity through the rope, which is a generating stage; the airbag is retracted to the initial position after moving for a certain distance, and the operation control system adjusts the windward angle of the airbag to ensure that the side of the airbag faces towards the wind and reversing winch on the ground is started to draws the airbag to the initial position along the upwind direction, which is a retraction stage. The two stages are alternately and circularly performed constantly.

Disclosed is an upper air spherical cavity turbo-type wind driven generator, which relates to the utilization of new energies. The upper air spherical cavity turbo-type wind driven generator comprises a helium balloon, a spherical turbo-type fan and a generator. The helium balloon lifts the wind driven generator composed of the spherical cavity turbo-type fan and the generator aloft and the wind driven generator utilizes the strong wind at the upper air and the advantages of low start-up wind speed, high safe wind speed, directional rotation, etc. of the spherical cavity turbo-type fan, makes full use of the wind power at the upper air to generate and transmits the power back to electrical equipment on the ground by cables. The wind driven generator overcomes the disadvantage that as the fan in the prior art is not so far away from the ground. the prior art cannot be used at areas with little strong wind at the shallow ground and solves the problems of high generating cost in the wind generation, difficulty in installing equipment, etc. of the prior art.

The invention provides a high altitude wind power generation system based on an unmanned aerial vehicle platform. The high altitude wind power generation system based on the unmanned aerial vehicle platform comprises a power generator arranged on the ground and a large wing face, high rising force and high lift-drag ratio unmanned aerial vehicle which drives a power generator to generate power. According to the high altitude wind power generation system based on the unmanned aerial vehicle platform, the aircraft is directly utilized for collecting wind energy in the air, building of a huge tower platform is omitted, and the structural design difficulty and the manufacturing cost are greatly reduced; because the aircraft can descend to the ground, installing and maintaining can both be performed on the ground, and therefore the installing and maintaining difficulty can be greatly reduced; under the conditions of typhoon and other severe weather, the system can be taken back, and therefore losses to a draught fan caused when the draught fan is exposed in typhoon and other disaster weather can be avoided, the disaster resistant capacity of the system is improved, and the service life of the system is prolonged; and a high altitude wind turbine wind rotor is small in size or no wind rotor exists, harm to birds can also be reduced.

The invention provides an aircraft and airship type high-altitude wind power generation device. An aircraft type kite is provided with a tube type rack and an automatic balance connection frame. An airship type hydrogen balloon is arranged on the automatic balance connection frame. Hub type blades are arranged on the right of the tube type rack. The lower left end of the tube type rack is provided with a high-speed permanent magnetic alternator and an intelligent control box. The hollow part of the tube type rack is provided with a sliding tube. A traction cable penetrates through a central hole of the sliding tube and is fixed. A pulley is arranged at the right end of the tube type rack. The traction cable passes through the pulley, is led out and hangs down. The lower end of the high-speed permanent magnetic alternator is provided with a power transmission cable. The power transmission cable and the traction cable converge to form a composite cable which is wound around an electric winch. The front end of a winding drum of the winch is provided with a generated power output socket. One branch of output alternate current is directly supplied to users after voltage transformation, and the other blanch of the output alternate current is used for charging a storage battery after commutating and voltage-stabilizing. With the elevation of the airship type hydrogen balloon, the high-altitude wind power generation device will not fall without wind, and therefore hidden safety hazards do not exist. When it is windy, the aircraft type kite is large in elevating force and easy to elevate, the traction cable is shortened, installation and control are easy, the diameter of the blades of a power generator is larger, and therefore the utilization rate of wind energy is high.

The invention relates to an altitude wind power generator for meeting the power demand in real life when existed wind power generator has many limits as high cost, the device is hard to installed, and limited landform. The invention comprises a buoyant balloon, blade wheels, a fixed connecting transmission and a generator. When the altitude wind power generator floating in the sky, the wind rotates the blade wheels and the fixed connecting transmission sends the wind power to ground to drive the generator. Utilizing said device, many shortages of wind power generator can be solved and the altitude generator can be realized.

The present invention relates to a air balloon suspension high altitude wind power generation equipment, which suspends the main wind power generation equipment to high altitude by air balloons; the suspension air balloon adopts kite balloon airship structure; the wind power generation equipment is provided with a constringency flow guiding intake tube and expansion exhausting pipe; particular high wind speed allows a wind motor either adopt windstick structure or turbine structure; tail and mooring circumgyrate hanging scaffold adjusts airship direction following wind direction to obtain upwind best wind utilization effect; horizontal wings are used to stabilize airship guise and increase auxiliary lift force; the airship is controlled by mooring up-down rope hoister to move up and down and positioned by mooring a plurality of ropes with hoister; electric energy is transmitted to ground by transmission lines or a microwave converter; and a ground support platform is mounted to setup airship mounting, maintain and elude hurricane. The beneficial effects of the present invention are as following: height of the wind power generating equipment is enhanced and wind energy is fully utilized; equipment is simplified, size is minimized and manufacture cost is reduced; convenient to mount, maintain and elude hurricane; can realize wind-power station in large size.

The invention discloses an aerial maintenance robot locating method and device based on near-earth global vision. By means of a double-vision system, the global position coordinates of a robot body and fault points are acquired through a first camera shooting module, and the robot body is controlled to carry out primary locating according to the obtained global position coordinates; and the localposition coordinates of the fault points are acquired through a second camera shooting module arranged at the tail end of a mechanical arm of the robot body, and the robot body is controlled to carryout secondary precise locating. According to the aerial maintenance robot locating method and device based on near-earth global vision, the first camera shooting module serving as a global camera is arranged at the near-earth end, and the technical problems that after the global camera ascends to a high altitude along with an insulation body, the camera bears the action of vibration of the mechanical arm during work and high-altitude wind power, camera disturbance is caused, then the precision of primary locating of the global camera is reduced, and the precision of secondary locating of the robot body is influenced is avoided.

An airborne electricity producing generator powered by wind at high altitude. A gas filled balloon keeps the turbines and other apparatus afloat. Connection with the ground is with tethers that also prevent the apparatus from floating freely and conduct electricity, thereby bringing the electricity produced to ground based transformers. Computer controls the position, direction, tilt and height of the apparatus depending on wind direction and speed.

The invention relates to a highaltitude wind energy and solar energy combined generator, which is a device for generating power through utilizing rich wind and solar resources at high altitude. The combined generator comprises an air bag, a vertical shaft windmill generator, a wind shielding body, a guy rope and a photovoltaic cell, wherein the windmill generator and the photovoltaic cell are carried by the air bag into the high altitude; one side of a wind wheel of the windmill generator is provided with the wind shielding body for keeping out the wind; the wind shielding body shields vanes rotating against the wind to make the vanes not influenced by airflows, but does not shield vanes rotating before the wind to make the vanes influenced by the airflows, so that the wind wheel is rotated under the action of the airflows to generate power; and the windward side of the wind shielding body is inclined downward, can gather the airflows to the vanes of the wind wheel which are not shielded, and can obtain upward lift force at the same time. The combined generator has the advantages that the combined generator has large electrical energy, and has cheap equipment compared with the prior tower power unit and low cost distributed to each kilowatt-hour; besides, the highaltitude windmill generator can not occupy great amount of field, and has no specific requirement on surface features of the ground.

The invention relate to a wind power generator, in particular to a wind power generator and device combination equipment driven by the same. The overhead wind power generator comprises a balloon and a generating device, wherein the generating device is connected with the balloon and a draught fan; the draught fan comprises a draught fan support and two rotors, wherein the two rotors are bilaterally symmetrically arranged in the draught fan support; flexible blades are arranged on the two rotors; and the flexible blades on one rotor are arranged oppositely to the flexible blades on the other rotor. Two rotors for the draught fan are adopted to drive the overhead wind power generating device to generate power, thus the high efficiency of the system is ensured. Compared with the traditional known wind power generator which adopts a transmitting belt or chain to transmit power to the ground to drive the wind power generator to generate power, the overhead wind power generator has greatly simplified structure.

The invention provides a high-altitude wind power generation system which comprises a vertical-axis wind turbine. A floating body for dragging the vertical-axis wind turbine to float in the air is arranged above the vertical-axis wind turbine. A transmission conductor is led out from the output end of the vertical-axis wind turbine and connected to a ground electric power storage system. The gravity center of the high-altitude wind power generation system is located in the straight line where a rotation shaft of a generator blade is located and located on the lower half portion of the vertical-axis wind turbine. The high-altitude wind power generation system can obtain strong electricity generation power under the conditions that the building cost is very low and a building site is relatively small.

Disclosed is a wing type vertical lift high-altitude wind power generation device. The upper end of a drum-shaped wing is provided with a wind speed sensor; the middle of the drum-shaped wing is provided with a window type double-driving fan; the middle of a cross frame of the window type double-driving fan is provided with a permanent magnet direct current motor which is used for driving a left fan blade and a right fan blade through gear shifting; a wireless intelligent control box and a sound and light alarm are arranged in front of and behind the motor respectively; the middle of the drum-shaped wing is a horizontal lifting power generator during take-off or falling; the lower end of the drum-shaped wing is transformed into a vertical wind power generator during high-altitude power generation; a left steel wire cable and a right steel wire cable of the drum-shaped wing are power transmission cables of the wireless intelligent control box and high-altitude traction cables of the drum-shaped wing; the ground located in front of the drum-shaped wing is provided with a steering support which can automatically rotate along with the wind direction; the lower end of the left steel wire cable and the lower end of the right steel wire cable wind a left electric hoist and a right electric hoist of the steering support respectively; the front end of the drum-shaped wing is provided with a left control cable and a right control cable; ground and high-altitude control motors are controlled by a hand control wireless remote control in a centralized mode. The wing type vertical lift high-altitude wind power generation device is reasonable in design, simple in structure and high in high-altitude wind energy utilization.

The invention relates to the technical field of wind power generation, in particular to a high-altitude wind power generation system which comprises a suspension balloon system, a wind wheel system and a terrestrial power generation system, wherein the suspension balloon system is connected with the wind wheel system through a connection strand, and thus the wind wheel system is suspended in the air; the wind wheel system is connected with a rotary shaft of a power generator in the terrestrial power generation system through dynamic ropes, and comprises a wind wheel composed of inflatable circular rings, fan blades and a spindle; coaxial rope discs are connected onto the wind wheel; a connection part is arranged at one end of the spindle, and fixed with the suspension balloon system through the connection strand; a plurality of pulleys and an auxiliary rope disc are fixed on the spindle; and the dynamic ropes are winded around and connected with the rope discs, the auxiliary rope disc, the pulleys and the rotary shaft of the terrestrial power generator, so that a linkage mechanism is defined by the wind wheel system and the rotary shaft of the power generator and used for driving the power generator to generate electricity through power transmission. The high-altitude wind power generation system can be mounted and connected onto the ground, thereby avoiding the danger of high-altitude operation in a tower structure; and the wind wheel can be raised or lowered as required, so that maintenance and repairing are facilitated.

The invention relates to a direct-drive ground generating set for high-altitude power generation, and belongs to the technical field of high-altitude wind power generation. The ground generating set comprises a generator and brakes, rollers, clutches and motors which are arranged on two sides of the generator symmetrically, wherein two ends of one roller and two ends of the other roller are connected with the brakes; two ends of a rotor shaft of the generator are connected with the brakes at one end of one roller and at one end of the other roller; the brakes at the other ends of the rollers are connected with the motors through the clutches; when the generator generates electricity, the two rollers are connected with an aerial work doing umbrella through ropes; and the two clutches are connected with an external control part and controlled to alternately work, so that the generator generates the electricity continuously, and the generated energy of the generator is improved. The ground generating set can transmit aerial mechanical energy to the ground; and the two clutches are controlled to alternately work by the external control part, so that the generator is in a working stateall the time.

The invention discloses a high-altitude wind power generation device. The device comprises multi-functional frames which are arranged symmetrically laterally. A plurality of wind power generators, a plurality of working cabins, a plurality of posture balance units and a plurality of suspension units are arranged in the multi-functional frames symmetrically laterally. A plurality of traction steel cables are arranged on the multi-functional frames symmetrically laterally. One end of each traction steel cable is connected with the multi-functional frame, and the other end is connected with a ground steel cable winch motor which is fixed on the ground. Cables are arranged at the electric output ends of the wind power generators. According to the device, most units are arranged at high altitudes, so that occupied area is small, the device can be built stereoscopically, effects on the wind site local production and life can be ignored, and the noise pollution, particularly, is almost equal to zero; the device can be built in some areas which are good in wind resource and dense in population, and the device can be assembled and lifted at any position without assembly in the wind field.

The invention discloses a ground wind generating set for high air power generation, and belongs to the technical field of high air wind power generation. The ground wind generating set comprises a generator, and couplers, speed increasing boxes, brakes, rollers, clutches and motors, which are symmetrically arranged on two sides of the generator; two ends of a rotor shaft of the generator are connected with the speed increasing boxes through the couplers; two ends of the rollers are connected with the brakes; the speed increasing boxes are connected with a brake at one end of the roller; the brake at the other end of the roller is connected with the motors through the clutches; and when the generator generates power, the two rollers are connected with a midair work doing umbrella through mooring ropes, and the two clutches are connected with an external control part and are controlled to alternately work, so that the generator continuously generates power and the power generation of the generator is improved. The ground wind generating set can transfer midair mechanical energy to the ground; and a rotating speed transmitted by the rollers is improved by the speed increasing boxes, so that a rotating speed at one end of an output shaft reaches a rated rotating speed required by the generator.

The invention discloses a wind power conversion mechanism. The wind power conversion mechanism comprises reciprocating wheels, a power generator, universal rope guiding mechanisms and traction cables, wherein the power generator is driven by the reciprocating wheels to generate electricity; the universal rope guiding mechanisms are arranged at two sides of the reciprocating wheels; and the traction cables are wound on the reciprocating wheels and are used for connecting with two ends of an aircraft to respectively wind the universal rope guiding mechanism at the corresponding side. The mechanism is compact in structure and stale in performance, can effectively avoid cable winding and can adapt to various wind directions, so that the wind power conversion efficiency can be obviously improved. The invention further discloses a high altitude wind power generator with the wind power conversion mechanism.

The invention provides a high-altitude orbit sailboard wind driven generator, comprising two or more than two annular tower posts which take a central tower post as the centre of circle and encircle around the central tower post; the top part of the annular tower post is installed with a horizontal annular orbit which takes the central tower post as the center of circle; a sports car is arranged on the annular orbit; even number of lower layer revolving arms of force are installed on the sports car and are evenly distributed in the radial direction along the center of the annular orbit; upper layer revolving arms of force with the number same as that of lower layer revolving arms of force are overlappingly installed above the lower layer revolving arms of force; opposite sides of the two ends of each group of upper and lower revolving arms of force are respectively provided with a yin and yang sailboard; a revolving gear is installed below the lower layer revolving arm of force and has the same center with the annular orbit; and a speed increasing gear is meshed with the revolving gear and is connected with the generator. The wind driven generator in the invention has simple structure, low construction cost, can utilize high-altitude wind to generate electricity safely and effectively, and increases single machine capacity of wind driven generator in the premise of ensuring safety running of wind driven generator.

The invention discloses a wind power conversion mechanism. The wind power conversion mechanism comprises reciprocating wheels, a generating-electromotion dual-purpose machine, universal rope guiding mechanisms and traction cables, wherein the reciprocating wheels comprise a first reciprocating wheel and a second reciprocating wheel; the generating-electromotion dual-purpose machine is in transmission connection with the first reciprocating wheel and the second reciprocating wheel through transmission parts; the universal rope guiding mechanisms are arranged at two sides of the reciprocating wheels; and the traction cables comprise a first cable and a second cable, the first cable is wound on the first reciprocating wheel, the second cable is reversely wound on the second reciprocating wheel, and the first cable and the second cable are used for connecting with one end of an aircraft to respectively wind the universal rope guiding mechanism at the corresponding side. The mechanism is compact in structure and stale in performance, can effectively avoid cable winding and can adapt to various wind directions, so that the wind power conversion efficiency can be obviously improved. The invention further discloses a high altitude wind power generator with the wind power conversion mechanism.

The invention discloses a wind energy conversion mechanism which comprises reciprocating wheels, a dual-purpose electric motor-generator, universal guide rope mechanisms and traction cable rope, wherein the reciprocating wheels comprise a first reciprocating wheel and a second reciprocating wheel; the dual-purpose electric motor-generator is connected with the first reciprocating wheel and the second reciprocating wheel through a clutch driving mechanism; the universal guide rope mechanisms are arranged on two sides of the reciprocating wheels; the traction cable ropes comprise a first cable rope and a second cable rope; the first cable rope is arranged on the first reciprocating wheel; the second cable rope is wound on the second reciprocating wheel; the first cable rope and the second cable rope are used for being connected with one end of an aircraft and come across the universal guide rope mechanisms on corresponding sides. The wind energy conversion mechanism is compact in structure and stable in performance, cable ropes are effectively prevented from being twisted, and the wind energy conversion mechanism is applicable to various wind directions, so that the wind energy conversion efficiency is remarkably improved. The invention further discloses an upper-air wind power generation device with the wind energy conversion mechanism.

The invention relates to a kite type high-altitude wind power generation device adopting transmission traction of a chain by wind pockets. The kite type high-altitude wind power generation device comprises a ground generator. The ground generator is connected with the bottom end of the transmission chain. The top end of the transmission chain is connected with a kite with a self-taking-off devicethrough a sheave wheel. The plurality of wind pockets are arranged on the transmission chain. The transmission chain is blown to fly at the high altitude under the action of the kite with the self-taking-off device at the top end, and the wind pockets are blown to drive the transmission chain to do transmission motion, so that the generator is driven to generate electricity. The ground generator is arranged in a machine room. The machine room is arranged on the machine room base. The machine room base is fixedly arranged on a rotary disc. The structure of the rotary disc is similar to that ofa thrust ball bearing. The kite type high-altitude wind power generation device can effectively utilize high-altitude strong and long-lasting wind power.

The invention relates to a high-altitude wind power generation device in the field of wind power generation. The wind power generation device comprises three parts including a high-altitude suspensiondevice, a traction cable and a ground recycling system. The high-altitude suspension device is a kite with multiple rotors, the high-altitude suspension device can be lifted up and down through the multiple rotors, and the multiple rotors can generate electricity. In the process of power generation at the high altitude, wind power can be generated by a sail, empennage windward area adjusting andswitching of the multiple rotors from the power generating state to the power consumption state to maintain the relative position of the suspension device at the high altitude, so that the high-altitude suspension device conducts suspension power generation within a certain space range. During multi-unit cluster distributed power generation, the high-altitude space utilization rate is improved, and it is ensured that the problems of position interference and cable entanglement cannot be caused when all units operate in coordination. In the manner, wind power generation is not limited by regions, and large-scale application can be achieved.

The invention relates to the technical field of wind electricity, in particular to a windward side self-adjusting high-altitude wind power generation device adopting the design that tail wind collecting vanes deviate from the central axis, windward side direction is adjusted automatically, and the windward side is enabled to face the direction of the wind always; a bearing mechanism is adopted tomake a first support to rotate by 360 degrees horizontally, and windward side stress on wind collecting vanes, caused by maintaining the windward side is eliminated; wind energy is collected by main wind collecting vanes, the tail wind collecting vanes and a front windward port and is introduced to a turbine motor at the bottom of a frame, and mechanical power of the turbine motor is converted into electricity through a generator; the turbine motor and the generator are located at the lower height of the frame, and installation and maintenance are facilitated; by the arrangement of suspensionropes, the frame can be integrally straightened and fixed through the ground suspension ropes, installation of the system is facilitated, strength of the system is enhanced, and meanwhile, the wind collecting mechanism can be placed at a higher height; the windward side self-adjusting high-altitude wind power generation device is simple in structure, convenient in preliminary production and installation, low in subsequent maintenance cost and suitable for promotion.

The invention relates to the field of high-altitude wind power generation, and particularly discloses a gravity tensioning device. The device further comprises several fixed pulley sets arranged parallelly and fixed to the upper portion of a rack and several movable pulleys arranged at the lower portion of the rack, wherein the fixed pulley sets comprise first fixed shafts installed on the rack, and several fixed pulleys are installed on the first fixed shafts; the movable pulleys are in one-to-one correspondence with the fixed pulleys and are further connected with balance weights, and the whole balance weights are in a tendency that the front portions are light, and the back portions are heavy. Compared with the prior art, the provided gravity tensioning device is a cable storage devicewith a cable buffering function, the buffering capacity is large, frictional loss of cables is less, and the device is beneficial for prolonging the service life of the cables.

The invention discloses a flexible coupler transmitting torque by mooring ropes, a wind power generator applying the flexible coupler, a dam-free floating type hydraulic power generator applying the flexible coupler or a generator applying the flexible coupler. The flexible coupler has the advantages that transmission of large torque is realized via the mooring ropes, the high-altitude wind power generator like a kite and the dam-free floating type hydraulic power motor are serially connected into a long series similar to a DNA (deoxyribose nucleic acid) spiral structure, high power in a single machine is achieved, and cost for generating power is greatly reduced; the power generating equipment and current delivering cables do not need to be put high in the sky, and only one kite is put into the sky, so that even crash will not cause severe damage.

The invention discloses an open sea anti-wave type hinged wind power installation vessel which comprises a wind power vessel body arranged on the sea surface, hinged connection parts, a wind power generation device arranged at the high altitude, a tower rotary disc and a mooring system and a submarine cable system. The wind power vessel body is composed of a plurality of annular vessel units and a center floating body called as a center island. The annular vessel units and the center floating body are connected into a whole through the hinged connection parts. The wind power generation device comprises front and rear wind wheels, a hub and a power generator room in the hub. The tower rotary disc is connected with the wind power vessel body and the wind power generation device arranged at the high altitude. The wind power vessel body and the seabed are connected through the mooring system and the submarine cable system.

The invention discloses a power confluence method of multiple high altitude wind generation sets for intermittent power generation, comprising the following steps of: respectively obtaining wind power from an air work-applying umbrella of each high altitude wind generating set, transmitting the obtained wind power to a ground winding drum by a tether, converting the obtained wind power into a mechanical power so as to drive a generator to generate electricity after accelerated by a gearbox, converting the current into a power-frequency three-phase AC (Alternating Current) by a full-power converter, and then carrying out the confluence of the power-frequency three-phase AC output by all high altitude wind generating sets and merging into the power network. By the technical scheme of the invention, the shortage of mechanical confluence can be overcome, and the power confluence of multiple high altitude wind generation sets for intermittent power generation is feasible.

The invention discloses a floating airbag of an aerial wind driven generator. The floating airbag comprises six independent helium airbags, a carbon fiber skeleton, empennages, rudders and a cross tail vane plate. A main body part of the airbag is formed by splicing six independent and annular helium airbags with different sizes, and supplies total lift; and the airbags are independent from each other to effectively prevent sharp fall of the generator caused by damage of the airbags, so that power generation equipment can be protected, the damage of ground facilities can be prevented, and the safety of lower persons is guaranteed. An internal frame structure of the airbag is produced by a carbon fiber synthesis material; and the material is mainly 30 mm-diameter carbon fibers / epoxy resin composite material pipes with different thicknesses. Three empennages are connected to the airbag by 120 degrees at intervals; two rudders are mounted on each empennage, and are controlled to operate by a stepper motor; and a fan is enabled to always align to the windward direction by dint of the wind power and the rudders. The cross tail vane plate is connected to a table-shaped carbon fiber skeleton in the airbag by a hydraulic extension rod, and bears the main direction control task.