JPWO2017086234A1 - Unmanned aerial vehicle - Google Patents

Abstract

Provided is an unmanned aerial vehicle capable of preventing the accident damage caused by a rotor blade after a crash when the aircraft collides with an obstacle during flight. An unmanned aerial vehicle including a plurality of rotor blades and a control unit that controls flight by the plurality of rotor blades, wherein the controller detects a collision between the aircraft and an obstacle to detect the plurality of rotor blades. The problem is solved by an unmanned aerial vehicle characterized by having emergency stop means for automatically stopping the vehicle. The unmanned aerial vehicle may further include a parachute injection mechanism, and the emergency stop unit may stop the plurality of rotor blades and deploy the parachute when the collision between the aircraft and the obstacle is detected. preferable.

Description

  The present invention relates to an unmanned aerial vehicle including a plurality of rotor blades, and more particularly to a technique for preventing an accidental damage caused by the rotor blades of the unmanned aircraft.

  Conventionally, a small unmanned aerial vehicle (UAV) represented by an industrial unmanned helicopter has been expensive and difficult to obtain, and requires skill in maneuvering for stable flight. However, in recent years, the performance and cost of airframe parts such as acceleration sensors and angular velocity sensors have been improved, and the operability has been dramatically improved by automating many of the airframe control operations. From such a background, the application of a small multi-copter to various missions in a wide range of fields is now being tried, not only for hobby purposes.

JP 2014-149622 A

  As an example of multi-copter flight control technology, there is a technology that avoids collision with obstacles by scanning obstacles around the aircraft with range sensors and automatically maintaining a certain distance from the obstacles. Are known. However, such a control technology is under development, and collision with an obstacle cannot be completely avoided.

  Also, the rotor blades of the multicopter are sharp, and if the multicopter collides with an obstacle, the rotor blades may damage it. After that, if the multicopter crashes while the rotor blade is driven, the rotor blade may damage the structure at the crash point, and if there is a passerby, the accidental damage may be serious. There is.

  In view of the above problems, the problem to be solved by the present invention is to provide an unmanned aerial vehicle capable of preventing the accident damage caused by a rotor after a crash when the aircraft collides with an obstacle during flight. It is in.

  In order to solve the above problems, an unmanned aerial vehicle of the present invention is an unmanned aerial vehicle including a plurality of rotary wings and a control unit that controls flight by the plurality of rotary wings, and the control unit includes: An emergency stop means for detecting a collision with an obstacle and stopping the plurality of rotor blades is provided.

  When the aircraft collides with an obstacle during the flight, the emergency stop means detects it and stops the rotor blade, thereby preventing the accident damage caused by the rotor blade after the crash.

  Further, it is preferable that a parachute injection mechanism is further provided, and the emergency stop means stops the plurality of rotor blades and deploys the parachute when the collision between the aircraft and the obstacle is detected.

  When an unmanned aerial vehicle crashes, the dropped aircraft may damage the structure of the crash site or injure passers-by. If the emergency stop means stops the rotor, the unmanned aircraft cannot escape the crash, but the emergency stop means automatically deploys the parachute in addition to stopping the rotor, reducing damage at the crash point of the aircraft It becomes possible to do.

  In addition, a rotor guard portion that protects each rotor blade from contact with an obstacle is provided, and the emergency stop means monitors the external force applied to the rotor guard portion, thereby It is good also as a structure which detects a collision.

  By providing the rotor guard portion on each rotor blade, it is possible to prevent the rotor blade from damaging the surrounding objects at least in the portion covered with the rotor guard portion. The unmanned aerial vehicle's rotor blades are usually placed at the top of the airframe and project to the outermost side in the horizontal direction of the airframe. That is, when an unmanned aerial vehicle collides with an obstacle, in many cases, the rotor blade first comes into contact with the obstacle. Therefore, it is possible to detect the collision between the unmanned aircraft and the obstacle with high accuracy by monitoring the external force applied to the rotor guard portion that protects the rotor blades.

  In addition, each of the rotor blades may be configured by a motor and a blade, and the emergency stop unit may detect a collision between the own machine and an obstacle by monitoring current consumption of each motor.

  The unmanned aerial vehicle's rotor blades are usually placed at the top of the airframe and project to the outermost side in the horizontal direction of the airframe. That is, when an unmanned aerial vehicle collides with an obstacle, in many cases, the rotor blade first comes into contact with the obstacle. In addition, the motor is characterized in that the amount of current increases or decreases depending on the load. When the rotor blade comes into contact with an obstacle, the amount of current of the motor changes suddenly and shows a value different from that during normal flight. By monitoring an abnormal change in current consumption of each motor and its continuation, it is possible to detect a collision between an unmanned aircraft and an obstacle.

  The control unit has an acceleration sensor, and the control unit monitors the consistency between a flight instruction from a pilot or a program and the output value of the acceleration sensor, and detects these inconsistencies. Sometimes, the emergency stop means may automatically stop the plurality of rotor blades.

  If the flight instructions given to the unmanned aircraft do not match the actual operation of the aircraft, it is suspected that the aircraft has become uncontrollable due to some disturbance or internal factor. By comparing the flight instruction to the unmanned aircraft with the output value of the acceleration sensor, it is possible to detect such a situation and automatically stop the rotating blades, thereby more reliably preventing the accident damage caused by the rotating blades. it can.

  As described above, according to the unmanned aerial vehicle according to the present invention, it is possible to prevent the accident damage caused by the rotor blade after the crash when the aircraft collides with an obstacle during the flight.

It is a block diagram which shows the function structure of the multicopter concerning 1st Embodiment. It is a block diagram which shows the function structure of the multicopter concerning 2nd Embodiment.

  Embodiments of an unmanned aerial vehicle according to the present invention will be described below with reference to the drawings.

<First Embodiment>
[Configuration overview]
FIG. 1 is a block diagram showing a functional configuration of a multicopter MC1 (unmanned aerial vehicle) according to the present embodiment. The multicopter MC1 includes a flight controller FC1 (control unit), a plurality of rotors 150 (rotary blades), an ESC 153 (Electric Speed Controller) arranged for each rotor 150, a rotor guard 300 (rotor guard unit) having an impact sensor 310, A parachute injection device (parachute injection mechanism), a wireless transmitter / receiver 170 that performs wireless communication with a pilot's control terminal 600, and a battery 180 that is a power supply source are provided in a casing 190.

  Each rotor 150 includes a motor 151 which is a DC motor, and a blade 152 attached to the output shaft thereof. The ESC 153 is connected to the motor 151 of the rotor 150, and is a device that rotates the motor 151 at a speed instructed by the flight controller FC1.

  The rotor guard 300 in the present embodiment is a frame that covers the outer side of the tip of the blade 152 of each rotor 150 in an arc shape or in an annular shape along the rotation trajectory of the blade 152. The rotor guard 300 is a protective member that prevents the blade 152 from coming into direct contact with an obstacle or the like, and may have a function of securing a flow path of air that is sucked and discharged by each rotor 150.

  The flight controller FC1 includes a control unit CU1 that is a microcontroller. The control unit CU1 includes a CPU 111 that is a central processing unit, a memory ST1 that is a storage device such as a ROM and a RAM, and a PWM controller 113 that controls the rotation speed and rotation speed of each motor 151 via the ESC 153.

  The flight controller FC1 further includes a flight control sensor group 130 and a GPS receiver 140 (hereinafter also referred to as “sensor or the like”), which are connected to the control unit CU1. The flight control sensor group 130 of the multicopter MC1 in the present embodiment includes an acceleration sensor, an angular velocity sensor, an atmospheric pressure sensor (altitude sensor), and a geomagnetic sensor (orientation sensor). The control unit CU1 uses these sensors and the like to position its own aircraft (hereinafter also referred to as “current position”) including the latitude and longitude of the aircraft, the altitude, and the azimuth angle of the nose, in addition to the tilt and rotation of the aircraft. Can be obtained.

  The memory ST1 of the control unit CU1 stores a flight control program 112, which is a program in which a flight control algorithm for controlling the attitude and basic flight operation of the multicopter MC1 during flight is stored. The flight control program 112 adjusts the rotation speed and rotation speed of each rotor 150 based on the current position acquired from the sensor or the like according to the instructions of the pilot (control terminal 600), and corrects the attitude and position disturbance of the aircraft. While flying the multicopter MC1. The multicopter MC1 may be manually operated by the operator using the operation terminal 600, or parameters such as latitude / longitude, altitude, and flight route are registered in advance in the flight control program 112, and then the destination is reached. You may fly autonomously (hereinafter, such autonomous flight is referred to as “autopilot”).

  The multicopter MC1 in the present embodiment uses a sensor or the like as its current position acquisition means, but the current position acquisition means of the present invention is not limited to these. For example, beacons corresponding to Bluetooth (registered trademark) Low Energy proximity profiles are arranged at predetermined intervals in a large-scale facility, and map information for partitioning the space shape in the facility is registered in the memory ST1 in advance. The current position of the multicopter MC1 in the facility may be specified by measuring the relative distance to the beacon. In addition, the multicopter MC1 in the present embodiment assumes that the flight altitude is obtained by a barometric sensor, but other than the barometric sensor, for example, measurement using various methods such as infrared rays, ultrasonic waves, or lasers is used. It is also possible to acquire the altitude by pointing the distance sensor toward the ground surface. Furthermore, the geographical feature is detected by scanning the surroundings of the aircraft with such a distance measuring sensor (or the geographical features are detected by image recognition from the video around the aircraft taken by the camera) The rough current position of the aircraft may be estimated by checking the registered geographical feature information on the flight route.

[Collision detection mechanism]
The memory ST1 of the control unit CU1 further includes an emergency stop which is a program for automatically stopping all the rotors 150 and developing the parachute from the parachute injection device 400 when a collision between the aircraft and the obstacle is detected. A program ES1 (emergency stop means) is stored.

  In addition, the multicopter MC1 is provided with a rotor guard 300 (rotor guard part) that protects the rotor 150 from contact with an obstacle. The rotor guard 300 is subjected to a sudden external force applied to the rotor guard 300. An impact sensor 310 to detect is arranged. The impact sensor 310 is connected to the control unit CU1, and its output is monitored by the emergency stop program ES1. For example, a pressure sensor can be used as the impact sensor 310. Such a pressure sensor may be a sensor that can electrically detect the deflection of the rotor guard 300 due to a collision with an obstacle. Further, the acceleration sensor of the flight control sensor group 130 can be applied without providing a separate pressure sensor as the impact sensor 310. The acceleration sensor of the flight control sensor group 130 constantly detects a change in position such as the inclination of the multicopter MC1, and can detect a collision relatively easily from the change pattern.

  In the multicopter MC1 of the present embodiment, the rotor guard 300 is provided in each rotor 150, so that the rotor 150 does not damage peripheral parts at least in a portion covered with the rotor guard 300. The rotor blades of unmanned airplanes are usually arranged at the top of the airframe and project to the outermost side in the horizontal direction of the airframe. The casing 190 of the multicopter MC1 has a structure that follows this (not shown). Therefore, when the multicopter MC1 in flight collides with an obstacle, it is assumed that the rotor guard 300 first contacts the obstacle. The multicopter MC1 of the present embodiment can detect a collision between the multicopter MC1 and an obstacle with high accuracy by providing an impact sensor 310 on the rotor guard 300 and monitoring its output with the emergency stop program ES1. It is said that.

[Emergency stop operation]
When the multicopter MC1 collides with an obstacle during manual operation of the multicopter MC1 or autonomous flight by an autopilot, the impact sensor 310 disposed on the rotor guard 300 outputs a signal indicating the occurrence of the collision. When the emergency stop program ES1 of the multicopter MC1 detects this output, it immediately stops the rotation of all the rotors 150 and deploys the parachute from the parachute injection device 400.

  The method for stopping the rotor 150 is not particularly limited. In addition to electronically stopping the rotor 150 by a normal control method, for example, by operating the parachute injection device 400 with a power supply line that supplies power from the battery 180 to the ESC 153. It is good also as composition cut off mechanically.

  When an unmanned aerial vehicle crashes, the dropped aircraft may damage the structure of the crash site or injure passers-by. The multicopter MC1 in the present embodiment is configured to stop the rotation of the rotor 150 by the emergency stop program ES1 and to automatically deploy the parachute, thereby reducing damage at the crash point of the aircraft. It is said that. Although it is desirable that the multicopter MC1 includes the parachute injection device 400, the parachute injection device 400 is not an essential component. In addition, the multicopter MC1 in the present embodiment operates the emergency stop program ES1 even during manual operation by the operator (control terminal 600), but the emergency stop program ES1 is executed only when autonomous flight is performed by an autopilot. It may be configured to operate.

Second Embodiment
Below, 2nd Embodiment of the unmanned aerial vehicle concerning this invention is described using drawing. FIG. 2 is a block diagram showing a functional configuration of a multicopter MC2 (unmanned aerial vehicle) according to the second embodiment. In the following description, components having the same functions as those of the previous embodiment are denoted by the same reference numerals as those of the previous embodiment, and detailed description thereof is omitted. In addition, regarding the configuration in which the basic function is common to the previous embodiment, only the end of the reference numeral of the previous embodiment is changed, and the description of the basic function is omitted.

[Configuration overview]
In the configuration of the multicopter MC2 according to the present embodiment, the rotor guard 300 (and the impact sensor 310) is removed from the multicopter MC1 according to the previous embodiment, and a current sensor 500 is newly disposed between each ESC 153 and the motor 151. It has been configured. The current sensor 500 is a sensor that measures the amount of current sent from the ESC 153 to the motor 151 and outputs it as a signal. In addition to the flight control program 112, the memory ST2 of the control unit CU2 included in the flight controller FC2 automatically stops all the rotors 150 when a collision between the aircraft and the obstacle is detected, and the parachute injection device An emergency stop program ES2 (emergency stop means), which is a program for developing a parachute from 400, is stored. The current sensor 500 is connected to the control unit CU2, and its output is monitored by the emergency stop program ES2.

[Collision detection mechanism]
The unmanned aerial vehicle's rotor blades are usually placed at the top of the airframe and project to the outermost side in the horizontal direction of the airframe. The casing 190 of the multicopter MC2 is also structured to follow this (not shown). Therefore, when the multicopter MC1 in flight collides with an obstacle, it is assumed that the rotor 150 first contacts the obstacle. In addition, the motor is characterized in that the amount of current increases or decreases depending on the load. In the multicopter MC2 of the present embodiment, the current sensor 500 is provided between each ESC 153 and the motor 151, and the output is monitored by the emergency stop program ES2. It is possible to detect a collision between the multicopter MC2 and an obstacle.

[Emergency stop operation]
When manual operation of the multicopter MC2 or autonomous flight by an autopilot, when the rotor 150 of the multicopter MC2 collides with an obstacle, the amount of current to the motor 151 changes suddenly and continues to be different from the normal value. To do. When the emergency stop program ES2 of the multicopter MC2 detects an abnormal change in the amount of current and / or the continuation of the abnormal value, the rotor of all the rotors 150 is forcibly stopped and the parachute is deployed from the parachute injection device 400. To do.

[Modification]
In this embodiment, the amount of current supplied to the motor 151 is monitored to indirectly detect a collision between the multicopter MC2 and an obstacle. Other methods for indirectly detecting a collision with an obstacle include, for example, a flight instruction from the control terminal 600 and the flight control program 112, and an output value of an acceleration sensor included in the flight control sensor group 130. It is conceivable to monitor the consistency of the program with the emergency stop program ES2.

  If the flight instructions given to the multicopter MC2 and the actual operation of the aircraft do not match, it is suspected that the aircraft has become uncontrollable due to some disturbance or internal factor. By comparing the flight instruction with respect to the multicopter MC2 and the output value of the acceleration sensor (that is, the actual movement direction of the aircraft) to detect such a situation, the rotation of the rotor 150 is forcibly stopped. It is possible to prevent the accident damage caused by In addition, according to this method, not only when the multicopter MC2 collides with an obstacle, for example, an accident in a situation where the aircraft continues to descend despite the fact that the throttle operation in the descending direction is not performed. Damage can also be suppressed. In addition, as a method for determining the consistency / inconsistency between the flight instruction to the multicopter MC2 and the actual operation, for example, a value obtained by acquiring these difference amounts that occur during normal flight and appropriately adding a margin value thereto. In addition, it is only necessary to determine that the inconsistency occurs when this criterion is exceeded by using as a criterion the addition of the duration of the inconsistent operation as a determination condition.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the present invention.

Claims (5)

An unmanned aerial vehicle comprising a plurality of rotor blades and a control unit that controls flight by the plurality of rotor blades,
The unmanned aerial vehicle according to claim 1, wherein the control unit includes an emergency stop unit that detects a collision between the own aircraft and an obstacle and automatically stops the plurality of rotor blades. Further equipped with a parachute injection mechanism,
2. The unmanned aerial vehicle according to claim 1, wherein the emergency stop unit automatically stops the plurality of rotor blades and deploys the parachute when a collision between the own aircraft and an obstacle is detected. . A rotor guard for protecting each rotor blade from contact with an obstacle;
The unmanned aerial vehicle according to claim 1, wherein the emergency stop unit detects a collision between the aircraft and the obstacle by monitoring an external force applied to the rotor guard unit. Each rotor blade is constituted by a motor and a blade,
The unmanned aerial vehicle according to claim 1 or 2, wherein the emergency stop means detects a collision between the aircraft and an obstacle by monitoring current consumption of each motor. The control unit has an acceleration sensor,
The control unit monitors the consistency between a flight instruction from a pilot or a program and the output value of the acceleration sensor, and when the mismatch is detected, the emergency stop means detects the plurality of rotor blades. The unmanned aircraft according to claim 1, wherein the unmanned aircraft is automatically stopped.

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