阅读说明：本技术 多旋翼无人飞行器的机架、农业植保无人机及控制方法 (Multi-rotor unmanned aerial vehicle frame, agricultural plant protection unmanned aerial vehicle and control method ) 是由 周乐 农贵升 李日照 于 2020-06-30 设计创作，主要内容包括：一种多旋翼无人飞行器的机架、农业植保无人机及控制方法。多旋翼无人飞行器的机架包括中心体(11)、多个机臂(12)、多个旋翼动力装置(13)、多个喷嘴(14)及多个角度调节机构(17)。旋翼动力装置(13)设于机臂(12)上。多个旋翼动力装置用于提供飞行动力给多旋翼无人飞行器。多个喷嘴(14)分别安装在多个机臂(12)的下方,并且分别位于旋翼动力装置(13)的下方。多个角度调节机构(17)分别设于多个机臂(12)上,且用于将机臂与中心体可转动连接。角度调节机构(17)能够调节机臂与中心体之间的夹角,使喷嘴的喷洒角度朝向中心体的斜下方。该农业植保无人机可以保证较多的树枝及树叶能够喷洒到农药,提高农业植保无人机对树木喷洒农药的均匀度。(A frame of a multi-rotor unmanned aerial vehicle, an agricultural plant protection unmanned aerial vehicle and a control method are provided. The frame of the multi-rotor unmanned aerial vehicle comprises a central body (11), a plurality of arms (12), a plurality of rotor power devices (13), a plurality of nozzles (14) and a plurality of angle adjusting mechanisms (17). The rotor wing power device (13) is arranged on the machine arm (12). A plurality of rotor power devices are used for providing flight power for the multi-rotor unmanned aerial vehicle. The plurality of nozzles (14) are respectively installed below the plurality of arms (12) and are respectively positioned below the rotor power device (13). A plurality of angle adjustment mechanisms (17) are respectively disposed on the plurality of horn arms (12) and are adapted to rotatably couple the horn arms to the central body. The angle adjusting mechanism (17) can adjust the included angle between the machine arm and the central body, so that the spraying angle of the nozzle faces the oblique lower side of the central body. This agricultural plant protection unmanned aerial vehicle can guarantee that more branch and leaf can spray the pesticide, improves agricultural plant protection unmanned aerial vehicle and sprays the degree of consistency of pesticide to trees.)

1. A multi-rotor unmanned aerial vehicle airframe, comprising:

a central body;

a plurality of horn distributed around the center body;

the rotor wing power devices are arranged on the horn and used for providing flight power for the multi-rotor wing unmanned aerial vehicle;

a plurality of nozzles mounted below the plurality of horn and below the rotor power plant, respectively; and

a plurality of angle adjustment mechanisms respectively arranged on the plurality of horn arms and used for rotatably connecting the horn arms with the central body;

the angle adjusting mechanism can adjust an included angle between the machine arm and the central body, so that the spraying angle of the nozzle faces to the oblique lower side of the central body.

2. The airframe according to claim 1, wherein a plurality of said arms are symmetrically distributed about the periphery of said central body.

3. The airframe according to claim 1, wherein said nozzles spray at an angle substantially perpendicular to said horn.

4. The airframe according to claim 1, wherein said rotor power unit comprises a motor and a blade, said motor drives said blade to rotate, and a spray angle of said nozzle is substantially parallel to a direction of a rotational axis of said blade.

5. The airframe of claim 1, wherein said arms include a pair of forward arms, a pair of aft arms; the front horn reaches the back horn all is equipped with the nozzle, it is a pair of front horn and a pair of back horn for many rotor unmanned vehicles's every single move axisymmetric setting.

6. The airframe according to claim 5, wherein a pair of said forward arms are symmetrically disposed about a roll axis of said multi-rotor unmanned aerial vehicle.

7. The airframe of claim 5, wherein said forward horn is disposed obliquely upward relative to a heading axis of said multi-rotor unmanned aerial vehicle.

8. The airframe according to claim 5, wherein said horn is at an acute angle relative to a roll axis of said multi-rotor unmanned aerial vehicle.

9. The airframe according to claim 5, wherein a spray angle of said nozzles associated with said leading arm is disposed obliquely relative to a heading axis of said multi-rotor unmanned aerial vehicle.

10. The airframe according to claim 5, wherein a spray angle of said nozzle with respect to said leading arm is inclined toward an outer side of said nose.

11. The airframe according to claim 5, wherein a pair of said rear arms are symmetrically disposed with respect to a roll axis of said multi-rotor unmanned aerial vehicle.

12. The airframe of claim 5, wherein said rear horn is disposed obliquely upward relative to a heading axis of said multi-rotor unmanned aerial vehicle.

13. The airframe according to claim 5, wherein the trailing arm is at an acute angle relative to a roll axis of the multi-rotor unmanned aerial vehicle.

14. The airframe according to claim 5, wherein a spray angle of said nozzles associated with said rear horn is disposed obliquely relative to a heading axis of said multi-rotor unmanned aerial vehicle.

15. The airframe according to claim 5, wherein a spray angle of the nozzle corresponding to the rear horn is set to be inclined toward an outer side of the tail.

16. The airframe according to claim 5, wherein a pair of said leading booms each carry a first rotor power plant and a pair of said trailing booms each carry a second rotor power plant, the axes of rotation of said first rotor power plants and said second rotor power plants being symmetrically disposed about the axis of rotation of said multi-rotor unmanned aerial vehicle.

17. The airframe of claim 16, wherein the first and second rotor power units have axes of rotation that are disposed at an angle relative to a heading axis of the multi-rotor unmanned aerial vehicle.

18. The airframe of claim 16, wherein the axes of rotation of said first and second rotor power units are angled downwardly toward the outside of said central body relative to the heading axis of said multi-rotor unmanned aerial vehicle.

19. The airframe of claim 16, wherein the axes of rotation of the first and second rotor power units are disposed obliquely relative to the roll axis of the multi-rotor unmanned aerial vehicle.

20. The airframe according to claim 5, wherein a pair of said leading arms each carry a first rotor power unit, a pair of said trailing arms each carry a second rotor power unit, a first nozzle corresponding to said first rotor power unit and a second nozzle corresponding to said second rotor power unit;

the spraying angles of the first nozzle and the second nozzle are obliquely arranged relative to the course axis of the multi-rotor unmanned aerial vehicle.

21. The airframe of claim 20, wherein a spray angle of said first and second nozzles is angled downwardly, toward an outboard side of said central body, relative to a heading axis of said multi-rotor unmanned aerial vehicle.

22. The airframe according to claim 20, wherein a spray angle of said first nozzle and said second nozzle is disposed obliquely to a roll axis of said multi-rotor unmanned aerial vehicle.

23. The airframe according to claim 5, wherein said arms comprise a pair of auxiliary arms, one of said auxiliary arms being disposed between said leading arms and the other of said auxiliary arms being disposed between said trailing arms.

24. The airframe of claim 23, wherein a pair of said auxiliary booms are symmetrically disposed about a pitch axis of said multi-rotor unmanned aerial vehicle.

25. The airframe of claim 23, wherein said auxiliary boom is disposed obliquely upward relative to a heading axis of said multi-rotor unmanned aerial vehicle.

26. The airframe according to claim 23, wherein a vertical projection of said auxiliary boom is along a roll axis of said multi-rotor unmanned aerial vehicle.

27. The airframe according to claim 23, wherein a spray angle of said nozzles associated with said secondary arms is disposed obliquely relative to a heading axis of said multi-rotor unmanned aerial vehicle.

28. The airframe according to claim 23, wherein a third rotor power plant is carried by each of said pair of auxiliary booms, and wherein an axis of rotation of said third rotor power plant of said pair of auxiliary booms is disposed symmetrically with respect to a heading axis of said multi-rotor unmanned aerial vehicle.

29. The airframe of claim 28 wherein the third rotor power plant axis of rotation is disposed obliquely relative to the multi-rotor unmanned aerial vehicle heading axis.

30. The airframe of claim 28, wherein the axis of rotation of said third rotor power plant is angled downwardly toward the outside of said central body relative to the heading axis of said multi-rotor unmanned aerial vehicle.

31. The airframe according to claim 28, wherein a vertical projection of the third rotor power plant's axis of rotation is disposed along a roll axis of the multi-rotor unmanned aerial vehicle.

32. The airframe of claim 28 wherein the axis of rotation of said third rotor power plant is disposed perpendicular to the pitch axis of said multi-rotor unmanned aerial vehicle.

33. The airframe according to claim 1, wherein said angle adjustment structure includes a rotating member connected to said horn, said rotating member rotating to adjust the angle between said horn and said central body.

34. The airframe according to claim 33, wherein said angular adjustment structure further comprises a locking member in limited engagement with said rotatable member to define an included angle between said horn and said central body.

35. The airframe according to claim 33, wherein said angle adjustment structure further comprises a drive member drivingly connected to said arm, said drive member rotating said rotatable member.

36. The airframe according to claim 35, wherein said rotor rotates as a result of said drive member telescoping movement.

37. The airframe according to claim 35, wherein rotation of said drive member rotates said rotor.

38. The airframe according to claim 1, wherein said horn comprises at least two rods and a horn telescoping mechanism, said rods being connected by said horn telescoping mechanism, said horn telescoping mechanism being adapted to adjust the length of said horn.

39. The airframe according to claim 1, wherein said horn is at an acute angle relative to a heading axis of said multi-rotor unmanned aerial vehicle.

40. The airframe according to claim 39, wherein said arms are angled from 45 to 80 degrees relative to a heading axis of said multi-rotor unmanned aerial vehicle.

41. The airframe according to claim 1, wherein said boom rotation relative to said central body includes a tree spray configuration and a non-tree spray configuration, and wherein said nozzle is inclined at an angle greater than 2 times an angle of inclination of said non-tree spray configuration.

42. A multi-rotor unmanned aerial vehicle airframe, comprising:

a central body;

a plurality of horn distributed around the center body;

the rotor wing power devices are arranged on the horn and used for providing flight power for the multi-rotor wing unmanned aerial vehicle; and

a plurality of nozzles mounted below the plurality of booms, respectively, and located below the plurality of rotor power plants, respectively;

wherein the plurality of horn comprises a pair of leading horn and a pair of trailing horn, the plurality of rotor power plant comprises a first rotor power plant disposed on the leading horn and a second rotor power plant disposed on the trailing horn, and the plurality of nozzles comprises a first nozzle corresponding to the first rotor power plant and a second nozzle corresponding to the second rotor power plant;

the pair of front arms and the pair of rear arms are symmetrically arranged relative to a pitching axis of the multi-rotor unmanned aerial vehicle, and the front arms and the rear arms are obliquely arranged upwards relative to a course axis of the multi-rotor unmanned aerial vehicle;

the rotating shaft of the first rotor wing power device and the rotating shaft of the second rotor wing power device are symmetrically arranged relative to the heading axis of the multi-rotor wing unmanned aerial vehicle; the rotating shafts of the first rotor power device and the second rotor power device are obliquely arranged relative to the course shaft of the multi-rotor unmanned aerial vehicle;

the spraying angles of the first nozzle and the second nozzle are obliquely arranged relative to the course axis of the multi-rotor unmanned aerial vehicle.

43. An agricultural plant protection unmanned aerial vehicle comprising a power source and the airframe of any one of claims 1-42, the power source being electrically connected to the rotor power plant.

44. An agricultural plant protection unmanned aerial vehicle, its characterized in that includes:

the form acquisition module is used for acquiring form information of an object to be sprayed;

the control module is used for receiving the form information and determining the spraying angle of the nozzle according to the form information; and

the angle adjusting mechanism is in signal connection with the control module and adjusts an included angle between the machine arm and the central body according to the spraying angle.

45. The agricultural plant protection drone of claim 44, wherein the control module is further configured to determine a spray length of the horn based on the shape information;

agricultural plant protection unmanned aerial vehicle still includes horn telescopic machanism, control module with horn telescopic machanism communication connection, horn telescopic machanism according to spray length adjustment the length of horn.

46. A control method of an agricultural plant protection unmanned aerial vehicle comprises the following steps:

collecting the shape information of the object to be sprayed;

determining the spraying angle of the nozzle according to the form information;

and adjusting the included angle between the machine arm and the central body according to the spraying angle.

47. The method for controlling an agricultural plant protection unmanned aerial vehicle of claim 46, wherein the shape information comprises a distance between two adjacent objects to be sprayed and a height of the objects to be sprayed.

48. The method for controlling an agricultural plant protection drone of claim 47, further comprising: and when the distance is smaller than a threshold value, determining the spraying length of the horn according to the form information, and adjusting the spraying length of the horn.

Technical Field

The invention relates to flight equipment, in particular to a rack of a multi-rotor unmanned aerial vehicle, an agricultural plant protection unmanned aerial vehicle and a control method.

Background

At present, when other spraying apparatus such as traditional agricultural plant protection unmanned aerial vehicle carried out the pesticide to plants such as fruit tree, cash crop and sprayed, because the growth direction of fruit tree branch disperses the growth in for the slant, outside leaf can shelter from inside branch, leaf production. When agricultural plant protection unmanned aerial vehicle's from the top sprays trees, the pesticide that sprays hardly pierces through sheltering from of leaf, evenly sprays the leaf of whole trees. Consequently, there is inhomogeneous, the not thorough technical problem of spraying to traditional agricultural plant protection unmanned aerial vehicle.

Disclosure of Invention

The invention provides a machine frame capable of improving the uniformity of pesticide spraying on trees.

A airframe for a multi-rotor unmanned aerial vehicle, comprising:

a central body;

a plurality of horn distributed around the center body;

the rotor wing power devices are arranged on the horn and used for providing flight power for the multi-rotor wing unmanned aerial vehicle;

a plurality of nozzles mounted below the plurality of horn and below the rotor power plant, respectively; and

a plurality of angle adjusting mechanisms respectively arranged on the plurality of machine arms and used for rotatably connecting the machine arms with the central body,

the angle adjusting mechanism can adjust an included angle between the machine arm and the central body, so that the spraying angle of the nozzle faces to the oblique lower side of the central body.

A airframe for a multi-rotor unmanned aerial vehicle, comprising:

a central body;

a plurality of horn distributed around the center body;

the rotor wing power devices are arranged on the horn and used for providing flight power for the multi-rotor wing unmanned aerial vehicle; and

a plurality of nozzles mounted below the plurality of booms, respectively, and located below the plurality of rotor power plants, respectively;

wherein the plurality of horn comprises a pair of leading horn and a pair of trailing horn, the plurality of rotor power plant comprises a first rotor power plant disposed on the leading horn and a second rotor power plant disposed on the trailing horn, and the plurality of nozzles comprises a first nozzle corresponding to the first rotor power plant and a second nozzle corresponding to the second rotor power plant;

the pair of front arms and the pair of rear arms are symmetrically arranged relative to a pitching axis of the multi-rotor unmanned aerial vehicle, and the front arms and the rear arms are obliquely arranged upwards relative to a course axis of the multi-rotor unmanned aerial vehicle;

the rotating shaft of the first rotor wing power device and the rotating shaft of the second rotor wing power device are symmetrically arranged relative to the heading axis of the multi-rotor wing unmanned aerial vehicle; the rotating shafts of the first rotor power device and the second rotor power device are obliquely arranged relative to the course shaft of the multi-rotor unmanned aerial vehicle;

the spraying angles of the first nozzle and the second nozzle are obliquely arranged relative to the course axis of the multi-rotor unmanned aerial vehicle.

The utility model provides an agricultural plant protection unmanned aerial vehicle, includes power and above-mentioned frame, the power with rotor power device electricity is connected.

An agricultural plant protection unmanned aerial vehicle, comprising:

the form acquisition module is used for acquiring form information of an object to be sprayed;

the control module is used for receiving the form information and acquiring the spraying angle of the nozzle;

the angle adjusting mechanism is in signal connection with the control module and adjusts an included angle between the machine arm and the central body according to the spraying angle.

A control method of an agricultural plant protection unmanned aerial vehicle comprises the following steps:

collecting the shape information of the object to be sprayed;

acquiring the spraying angle of the nozzle according to the form information;

the included angle between the horn and the central body is adjusted according to the spray angle.

Above-mentioned rotor unmanned vehicles's frame can be adjusted the horn for the contained angle between the central body through angle adjustment mechanism, and then realizes adjusting the angle of spraying of the nozzle of locating on the horn. When the spray angle of the nozzle is directed obliquely below the central body, the spray angle can be directed towards the branches, in the direction of growth of the branches. When above-mentioned agricultural plant protection unmanned aerial vehicle is located one side of trees, then only less leaf is sheltered from spraying the pesticide production on the angle of spraying of nozzle, guarantees that more branch and leaf can spray the pesticide, improves the degree of consistency that agricultural plant protection unmanned aerial vehicle sprayed the pesticide to trees.

And, above-mentioned agricultural plant protection unmanned aerial vehicle can obtain the spraying angle of nozzle according to the form information of waiting to spray the thing through above-mentioned control method to can correspond the contained angle between regulation horn and the central body, make the spraying angle of nozzle towards the oblique below of central body. The spray angle of the nozzle can be directed towards the branch, in the direction of growth of the branch. When above-mentioned agricultural plant protection unmanned aerial vehicle is located one side of trees, then only less leaf is sheltered from spraying the pesticide production on the angle of spraying of nozzle, guarantees that more branch and leaf can spray the pesticide, improves the degree of consistency that agricultural plant protection unmanned aerial vehicle sprayed the pesticide to trees.

Drawings

Fig. 1 is a schematic view of a use state of the agricultural plant protection unmanned aerial vehicle according to the embodiment;

fig. 2 is a perspective view of the agricultural plant protection drone shown in fig. 1;

fig. 3 is a simple structure diagram of the agricultural plant protection unmanned aerial vehicle of the embodiment;

fig. 4 is another simple structure diagram of the agricultural plant protection unmanned aerial vehicle of the embodiment;

fig. 5 is a simple structure diagram of the angle adjustment structure of the agricultural plant protection unmanned aerial vehicle according to the embodiment;

FIG. 6 is a simplified block diagram of another embodiment of the angle adjustment structure shown in FIG. 5;

fig. 7 is a schematic structural diagram of an electrical module of the agricultural plant protection unmanned aerial vehicle according to the embodiment;

fig. 8 is a flowchart of a control method of the agricultural plant protection unmanned aerial vehicle according to the embodiment;

fig. 9 is another flowchart of the control method of the agricultural plant protection unmanned aerial vehicle shown in fig. 8.

X, a transverse rolling shaft; y, pitch axis; z, a course axis;

1. an agricultural plant protection unmanned aerial vehicle; 9. a power source; 10. a frame; 11. 21, a central body;

12. 22, a machine arm; 121. a front horn; 122. a rear boom; 123. an auxiliary machine arm; 125. a boom extension structure;

13. a rotor power plant; 131. a first rotor power plant; 132. a second rotor power plant; 133. a third rotor power plant; 1311. 1321, 1331, a rotating shaft;

14. a nozzle; 141. a first nozzle; 142. a second nozzle; 143. a third nozzle;

145. a pipeline; 15. a water tank; 16. a foot rest;

17. 27, an angle adjusting structure; 171. 271, a rotating member; 172. 272, a driving member; 18. a form acquisition module; 19. and a control module.

Detailed Description

Exemplary embodiments that embody features and advantages of the invention are described in detail below in the specification. It is to be understood that the invention is capable of other embodiments and that various changes in form and details may be made therein without departing from the scope of the invention and the description and drawings are to be regarded as illustrative in nature and not as restrictive.

This embodiment provides an agricultural plant protection unmanned aerial vehicle. Agricultural plant protection unmanned aerial vehicle is used for the unmanned aircraft of agriculture and forestry plant protection operation. This type agricultural plant protection unmanned aerial vehicle flies the accuse through ground remote control or navigation, comes to treat to spray the thing and realizes spraying the operation. The object to be sprayed can be trees, crops and the like. Agricultural plant protection unmanned aerial vehicle can spray medicament, seed, powder etc..

Specifically, in the present embodiment, please refer to fig. 1, the agricultural warranty drone 1 is described by taking the case of spraying a chemical. And, the object to be sprayed is illustrated by taking the tree 2 as an example. The agricultural quality control unmanned aerial vehicle 1 can spray two trees 2 between the two trees 2.

The agricultural plant protection unmanned aerial vehicle 1 of this embodiment includes power 9 and frame 10. The power provides the electric quantity for the normal work of agricultural plant protection unmanned aerial vehicle. The frame is a frame of a multi-rotor unmanned aerial vehicle.

Specifically, in this embodiment, airframe 10 of a multi-rotor unmanned aerial vehicle includes a hub 11, a plurality of arms 12, a plurality of rotor power plants 13, and a plurality of nozzles 14.

The central body 11 may serve as a central reference for the frame 10. A plurality of horn 12 are distributed around the center body 11, centering on the center body 11. The rotor power plant 13 is arranged on the horn 12. Multiple rotor power plants 13 may provide flight power for a multi-rotor unmanned aerial vehicle. The plurality of nozzles 14 are installed below the plurality of arms 12, respectively, and below the rotor power unit 13, respectively. The nozzle 14 is used for spraying a medicament.

According to the shape of waiting to spray the thing of difference and spray the demand, utilize angle adjustment mechanism adjusting nozzle 14 spray the angle to the realization is treated spraying the comparatively accurate implementation of thing and is sprayed, and improve the degree of consistency when agricultural plant protection unmanned aerial vehicle 1 treats spraying the thing and sprays.

Moreover, the frame of the multi-rotor unmanned aerial vehicle further comprises a foot rest 16. The foot rest 16 is provided below the central body 11 for supporting the central body 11, the horn 12, the rotor power unit 13 and the nozzle 14. Furthermore, the foot rest 16 can be folded on the central body 11 to facilitate the storage and transportation of the multi-rotor unmanned aerial vehicle.

Referring to fig. 2, in this embodiment, the plurality of arms 12 of the frame 10 are symmetrically distributed on the outer periphery of the central body 11. During flight of the rotorcraft, the central body 11 lies in a plane parallel to the horizontal plane to ensure that the airframe 10 is balanced. For ease of illustration, a rotary-wing unmanned aerial vehicle includes 3 axes of motion. Namely, the roll axis along the direction of the nose and the tail is marked as X; on the horizontal plane, a pitching axis perpendicular to the rolling axis X is marked as Y; the heading axis perpendicular to the horizontal plane and perpendicular to both the roll axis X and the pitch axis Y is designated as Z.

A rotor power unit 13 is supported above the horn 12, and faces the rotor power unit 13, and a nozzle 14 is provided below the horn 12. The spray from the nozzle 14 can be accelerated in speed and area under the influence of the wind from the rotor power unit 13.

A water tank 15 is also carried on the frame 10. The water tank is disposed on the central body 11. The water tank 15 may be one or more. Then the frame 10 is loaded with a plurality of water tanks 15 simultaneously and can improve the medicine carrying capacity of the agricultural plant protection unmanned aerial vehicle 1 to improve the spraying efficiency of the agricultural plant protection unmanned aerial vehicle 1. The nozzle 14 may communicate with the tank 15 via a line 145. Further, a water pump and a control valve are provided in the pipe 145 to control the communication state of the nozzle 14.

Specifically, in the present embodiment, the horn 12 includes six. The six wings are symmetrically distributed on the periphery of the central body 11. The included angle between two adjacent wings is 60 degrees, so that the frame 10 can be ensured to be smoothly kept balanced.

Referring to fig. 3, the angle between the horn 12 and the heading axis Z of the multi-rotor unmanned aerial vehicle is acute. The included angle between the horn 12 and the course axis Z of the multi-rotor unmanned aerial vehicle is 45-80 degrees. The arms 12 are all drawn towards the course axis Z above the central body 11, the arms 12 being arranged at an angle to the plane of the central body 11. The spray angle of the nozzle 14 on the horn 12 is directed obliquely downwards towards the central body 11.

In particular, in this embodiment, the angle between the horn 12 and the hub 11 is adjustable. The rotational position of the horn 12 relative to the hub 11 includes a tree spray position and a non-tree spray position.

When spraying of trees is desired, the horn 12 is rotated relative to the hub 11 and the horn 12 is in a tree spraying position. The spray angle of the nozzle 14 is directed obliquely downwards towards the central body 11 due to the shadowing of the leaves of the trees. In the tree spraying state, the inclination angle of the horn 12 relative to the central body 11 can be approximately referenced to the growth angle of the tree branches, so that the spraying angle of the nozzle 14 is just along the growth direction of the tree branches. Then only less leaf is sheltered from spraying the pesticide production on the angle of spraying of nozzle 14, guarantees that more branch and leaf can spray the pesticide, improves the degree of consistency that agricultural plant protection unmanned aerial vehicle 1 sprayed the pesticide to trees.

When spraying of trees is not desired, or when spraying of non-trees is desired, the horn 12 can be rotated back relative to the hub 11 to place the horn 12 in a non-tree spraying condition. It will be appreciated that the angle between the horn 12 and the central body 11 is much less than the angle of inclination of the horn 12 in the tree spraying position when the horn 12 is in the non-tree spraying position. Even more, the inclination angle of the nozzle 14 in the tree spraying state may be zero degrees. In the non-tree spraying state, the arm 12 has a small inclination angle relative to the central body 11, which can enlarge the spraying area of the nozzle 14 and is beneficial to controlling the flight state of the multi-rotor unmanned aerial vehicle. Or when there is no included angle between the horn 12 and the central body 11, the horn 12 is parallel to the plane of the central body 11, the power applied to the horn 12 is perpendicular to the direction of the horn 12, and the multi-rotor unmanned aerial vehicle can fly at a high flying speed.

Also, the angle of inclination of the nozzle 14 in the tree spraying state is much greater than the angle of inclination of the nozzle 14 in the non-tree spraying state. Specifically, the inclination angle of the nozzle 14 in the tree spraying state is greater than 2 times the inclination angle in the non-tree spraying state. The angle of inclination with respect to the vertical direction,

referring to fig. 4, specifically, the boom 12 includes a pair of front booms 121, a pair of rear booms 122 and a pair of auxiliary booms 123. A pair of front arms 121 are closer to the head. A pair of rear booms 122 are near the aft direction. One auxiliary arm 123 is disposed between the two front arms 121, and the other auxiliary arm 123 is disposed between the two rear arms 122.

The pair of front arms 121 and the pair of rear arms 122 are disposed symmetrically with respect to the pitch axis Y of the multi-rotor unmanned aerial vehicle. The pair of auxiliary arms 123 is symmetrically disposed with respect to the pitch axis Y of the multi-rotor unmanned aerial vehicle. Therefore, the front arm 121, the rear arm 122 and the auxiliary arm 123 which are symmetrically arranged about the pitch axis Y can ensure that the nose and the tail of the multi-rotor unmanned aerial vehicle keep balanced front and back.

The pair of front arms 121 are symmetrically disposed with respect to the roll axis X of the multi-rotor unmanned aerial vehicle. The pair of rear arms 122 are symmetrically disposed with respect to the roll axis X of the multi-rotor unmanned aerial vehicle. The vertical projection of auxiliary boom 123 is along the roll axis X of the multi-rotor unmanned aerial vehicle. The front arm 121 and the rear arm 122 are symmetrically arranged about the transverse axis X, so that the stresses on the left and right sides of the frame 10 of the multi-rotor unmanned aerial vehicle are kept balanced.

The angle of the front arm 121 with respect to the roll axis X of the multi-rotor unmanned aerial vehicle is acute. The rear horn 122 is at an acute angle relative to the roll axis X of the multi-rotor drone. Specifically, in the present embodiment, the angle between the front arm 121 and the roll axis X is 20 to 70 degrees. The angle between the rear arm 122 and the roll axis X is 20-70 degrees.

Specifically, the angle between the front arm 121 and the roll axis X is 60 degrees. The rear arm 122 is also at an angle of 60 degrees to the roll axis X. The angle between the auxiliary arm 123 and the roll axis X is 0 degrees. Then, the included angle between two adjacent front horn 121, rear horn 122 and auxiliary horn 123 is 60 degrees, so that the balance of the frame 10 of the multi-rotor unmanned aerial vehicle can be easily ensured.

The nose arm 121 is disposed obliquely upward with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. I.e. there is an angle between the horn 121 and the hub 11. The front arm 121 is disposed obliquely upward with respect to the horizontal plane. The angle of the horn 121 relative to the heading axis Z is acute. Specifically, the angle between the front arm 121 and the heading axis Z is between 45 degrees. The problem that the normal balance flight of the multi-rotor unmanned aerial vehicle is influenced due to the fact that the included angle between the front horn 121 and the course axis Z is too large is avoided.

And, rear horn 122 is disposed obliquely upward with respect to heading axis Z of the multi-rotor unmanned aerial vehicle. I.e. the rear horn 122 is angled from the central body 11. The rear arm 122 is disposed obliquely upward with respect to the horizontal plane. The rear horn 122 is at an acute angle relative to the heading axis Z. Specifically, the angle between the rear arm 122 and the heading axis Z is between 45 degrees. The problem that the normal balance flight of the multi-rotor unmanned aerial vehicle is influenced due to the fact that the included angle between the rear arm 122 and the course axis Z is too large is avoided.

The auxiliary boom 123 is disposed obliquely upward relative to the heading axis Z of the multi-rotor unmanned aerial vehicle. I.e. the auxiliary horn 123 is angled with respect to the central body 11. The auxiliary horn 123 is disposed obliquely upward with respect to the horizontal plane. The auxiliary boom 123 is at an acute angle relative to the heading axis Z. Specifically, the angle between the auxiliary boom 123 and the heading axis Z is between 45 degrees. The problem that the normal balance flight of the multi-rotor unmanned aerial vehicle is influenced due to the fact that the included angle between the auxiliary horn 123 and the course axis Z is too large is avoided.

Rotor power device 13 work provides power for agricultural plant protection unmanned aerial vehicle 1. The rotor power device 13 comprises a motor 138 and a blade 139, the motor 138 drives the blade 139 to rotate, and the spraying angle of the nozzle 14 is influenced by the airflow generated by the rotation of the blade 139. Thus, the spray angle of the nozzle 14 is substantially parallel to the direction of the axis of the rotation axis. The motor 138 is electrically connected to the power source 9 and is powered by the power source 9.

Specifically, in this embodiment, rotor power assembly 13 includes a first rotor power assembly 131 carried on a pair of forward booms 121, a second rotor power assembly 132 carried on a pair of aft booms 122, and a third rotor power assembly 133 carried on a pair of auxiliary booms 123.

Rotation axis 1311 of first rotor power plant 131 and rotation axis 1321 of second rotor power plant 132 are symmetrically disposed with respect to heading axis Z of the multi-rotor drone. The rotation axes of first rotor power plant 131 and second rotor power plant 132 are disposed obliquely with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle.

The rotation axes of first rotor power unit 131 and second rotor power unit 132 are disposed obliquely with respect to roll axis X of the multi-rotor unmanned aerial vehicle.

The axes of rotation of first rotor power plant 131 and second rotor power plant 132 are tilted downward toward the outside of central body 11 with respect to heading axis Z of the multi-rotor unmanned aerial vehicle.

Third rotor power plant 133 has its axis of rotation 1331 symmetrically disposed with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The power received by the auxiliary boom 123, provided by the third rotor power plant 133, can be arranged symmetrically with respect to the heading axis Z, ensuring the balance of the airframe 10.

Third rotor power plant 133 has its axis of rotation 1331 disposed at an angle with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The vertical projection of the axis of rotation 1331 of third rotor power plant 133 is disposed along the roll axis X of the multi-rotor unmanned aerial vehicle. Third rotor power plant 133 has its axis of rotation 1331 tilted downward toward the outside of central body 11 with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle.

In other embodiments, the axis of rotation 1331 of third rotor power plant 133 is disposed perpendicular to the pitch axis Y of the multi-rotor unmanned aerial vehicle. The power provided by third rotor power plant 133 is perpendicular to pitch axis Y of the multi-rotor drone, and the pitch angle of the multi-rotor drone can be adjusted more easily.

Referring to fig. 2 and 3, the spray angle of the nozzle 14 is substantially perpendicular to the arm 12. Specifically, a first nozzle 141 is correspondingly disposed on the front arm 121. Correspondingly disposed on the rear arm 122 is a second nozzle 142. Correspondingly disposed on the auxiliary arm 123 is a third nozzle 143. First nozzle 141 is disposed in correspondence with first rotor power plant 131. The second nozzle 142 is disposed in correspondence with the second rotorcraft. Third nozzle 143 is positioned in relation to third rotor power plant 133.

The direction of the rotation axis of the first rotor power unit 131 is the spraying angle of the first nozzle 141. The direction of the axis of rotation of second rotor power plant 132 is the spray angle of second nozzle 142. The direction of the axis of rotation of third rotor power plant 133 is the spray angle of third nozzle 143.

The spray angle of the first nozzle 141 is set obliquely with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The spraying angle of the first nozzle 141 is obliquely arranged toward the outside of the head.

The second nozzle 142 has a spray angle that is obliquely disposed with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The spraying angle of the second nozzle 142 is obliquely arranged toward the outer side of the tail.

The spraying angles of the first nozzle 141 and the second nozzle 142 are set to be inclined with respect to the roll axis X of the multi-rotor unmanned aerial vehicle.

The first nozzle 141 and the second nozzle 142 have a spray angle that is inclined downward toward the outside of the center body 11 with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle.

In this embodiment, the above-mentioned agricultural plant protection unmanned aerial vehicle 11 is used for evenly spraying about the leaf to trees 2. Therefore, the main movement of the agricultural plant protection unmanned aerial vehicle 1 is the up-and-down movement. Therefore, the spray from the third nozzle 143 is less affected by the flight airflow.

The third nozzle 143 has a spray angle that is set obliquely with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The third nozzle 143 has a spray angle that is downwardly inclined toward the outside of the center body 11 with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The spraying angle of the third nozzle 143 may be along the growth direction of the trees to spray as uniformly as possible.

And, the vertical projection of the spray angle of the third nozzle 143 is disposed along the roll axis X of the multi-rotor unmanned aerial vehicle. The third nozzle 143 has a spray angle toward the outside of the head or tail. Therefore, the spraying angle of the third nozzle 143 is helpful to achieve uniform spraying of the tree leaves; on the other hand, the third nozzle 143 may also spray a spray that is located further away from the side of the central body 11.

In other embodiments, the third nozzle 143 may be omitted. Since the auxiliary arms 123 are disposed in the X direction of the traverse axis, that is, the two auxiliary arms 123 are respectively disposed at the head and the tail. The third nozzle 143 is disposed at the head and tail positions. When the above-mentioned agricultural plant protection unmanned aerial vehicle 1 flies forward and backward, the spray from the third nozzle 143 is affected by the flying airflow and falls on the central body 11. Since the central body 11 is provided with electrical components, the spray stays on the central body 11 for a long time, which may cause damage to the electrical components.

And, the power provided by third rotor power plant 133 on auxiliary horn 123 may assist airframe 10 in maintaining balanced flight.

Referring to fig. 5, in the present embodiment, the frame 10 further includes an angle adjusting structure 17 for adjusting an included angle between the arm 12 and the central body 11. A plurality of angle adjustment structures 17 are respectively provided on the plurality of horn 12 and are used to rotatably couple the horn 12 to the central body 11. The angle adjustment mechanism is capable of adjusting the angle between the horn 12 and the central body 11 such that the spray angle of the nozzle 14 is directed obliquely below the central body 11. The angle adjusting structure 17 may be provided on each horn 11, or the angle adjusting structure 17 may be provided on a part of the horns 11. As long as the symmetrical arrangement of the plurality of arms 11 can be ensured, the frame 10 can be kept balanced during flight. The relationship between the number of the angle adjusting structures 17 and the number of the horn 11 is not limited herein.

The angle adjusting structure 17 may include a rotation member 171. The rotor 171 is connected to the arm 12. The rotation member 171 rotates to adjust the angle between the arm 12 and the central body 11.

In this embodiment, the angle adjusting structure 17 may further include a locking member (not shown). The locking member is in limited engagement with the rotatable member 171 to define the angle between the horn 12 and the hub 11. After the angle between the horn 12 and the hub 11 is determined, the angle between the horn 12 and the hub 11 is locked by a locking member.

The rotating member 171 may be a rotating shaft. The arm 12 rotates relative to the shaft, and the angle between the arm 12 and the central body 11 is adjusted. When the position is adjusted, the machine arm 12 is limited and fixed through the locking piece. The locking piece can be a bolt, a limiting clamping piece and the like.

The angle adjustment structure 17 further includes a driving member 172, the driving member 172 is drivingly connected to the arm 12, and the driving member 172 rotates the rotating member 171.

The rotation of the driving member 172 drives the rotation of the rotating member 171. The driving member 172 is directly rotatably connected to the rotating member 171. The driving member 172 may be a motor or a rotating shaft. The rotation member 171 may be a gear, a bushing, or the like. The driving member 172 can drive the rotation member 171 to rotate, and the rotation member 171 rotates to drive the arm 12 to rotate, so as to change the angle between the arm 12 and the central body 11.

Referring to fig. 6, in another embodiment, the driving member 272 expands and contracts to drive the rotating member 271 to rotate. The driving member 172 can move telescopically. The driving member 272 may be a telescopic rod of a telescopic motor, a telescopic screw rod, a telescopic motor, or the like. The telescopic end of the driving member 272 is fixedly connected to the horn 22, and the telescopic end is extended and contracted, so that the size of the included angle between the horn 22 and the central body 21 can be adjusted.

In other embodiments, the angle adjustment structure 17 may also be omitted. The angle between the horn 12 of the multi-rotor unmanned aerial vehicle in this embodiment relative to the central body 11 is not adjustable. The horn 12 is fixedly disposed at the outer circumference of the central body 11 at a fixed inclination angle. Then the multi-rotor unmanned aerial vehicle can also realize that: the spray direction of the nozzle 14 on the horn 12 is directed obliquely downwards towards the central body 11. Agricultural plant protection unmanned aerial vehicle 1 that contains this frame 10 can guarantee equally that more branch and leaf can spray the pesticide, improves the degree of consistency that agricultural plant protection unmanned aerial vehicle 1 sprayed the pesticide to trees.

In another embodiment, auxiliary boom 123, third nozzle 143, and third rotor power unit 133 may be omitted from frame 10 of the multi-rotor unmanned aerial vehicle.

The airframe 10 of the multi-rotor unmanned aerial vehicle of this embodiment is a four-rotor airframe. The frame's horn 12 includes a pair of front horns 121 and a pair of rear horns 122. The plurality of rotor power units 13 include a first rotor power unit 131 provided on the front horn 121 and a second rotor power unit 132 provided on the rear horn 122, and the plurality of nozzles 14 include a first nozzle 141 corresponding to the first rotor power unit 131 and a second nozzle 142 corresponding to the second rotor power unit 132.

The pair of front arms 121 and the pair of rear arms 122 are disposed symmetrically with respect to the pitch axis Y of the multi-rotor unmanned aerial vehicle, and the front arms 121 and the rear arms 122 are disposed obliquely upward with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The rotation axis of first rotor power plant 131 and the rotation axis of second rotor power plant 132 are symmetrically disposed with respect to multi-rotor drone heading axis Z. The rotation axes of first rotor power plant 131 and second rotor power plant 132 are disposed obliquely with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle. The spray angles of the first nozzle 141 and the second nozzle 142 are set obliquely with respect to the heading axis Z of the multi-rotor unmanned aerial vehicle.

The nozzles 14 on the horn 12 of the multi-rotor drone thus all spray at an angle obliquely downwards towards the central body 11. Agricultural plant protection unmanned aerial vehicle 1 that contains this frame can guarantee equally that more branch and leaf can spray the pesticide, improves the degree of consistency that agricultural plant protection unmanned aerial vehicle 1 sprayed the pesticide to trees.

Still provide an agricultural plant protection unmanned aerial vehicle. Referring to fig. 7, the agricultural plant protection unmanned aerial vehicle includes a form acquisition module 18, a control module 19, and an angle adjustment mechanism 17.

The form acquisition module 18 is used for acquiring form information of the object to be sprayed. The shape information comprises the space size of two adjacent objects to be sprayed and the height of the objects to be sprayed. When the object to be sprayed is a tree, the collected form information can be the size of the space between two adjacent trees, the distance between the bottom branch and the top branch of the tree, the length information of the bottom branch and the top branch, the growth angle of the tree branches and the like.

Wherein, the growth angle of the tree branches is the included angle between the growth direction of the branches and the vertical direction. The horn 12 is inclined relative to the central body 11 and the angle between the horn 12 and the heading axis Z is approximately the same as the growing angle of the tree branches so that the spraying direction of the nozzle 14 sprays along the growing direction of the tree branches.

The form acquiring module 18 may be a scanner, a distance sensor, a camera, or the like.

The control module 19 is used for receiving the form information. The control module 19 determines the spray angle of the acquisition nozzle 14 according to the shape information.

The control module 19 can obtain the branch growth angle of the tree according to the shape information of the tree. And, the control module 19 can also control the whole flight process of the agricultural plant protection unmanned aerial vehicle 1 according to the form information of the trees.

The control module 19 may also be used to determine the spray length of the horn 12 based on the shape information. When the interval between two adjacent trees is less, this interval is less than the flight diameter size of frame, then this agricultural plant protection unmanned aerial vehicle 1 can not enter into between two adjacent trees. The agricultural plant protection unmanned aerial vehicle 1 must adjust the length of the arm 12 to reduce the flight diameter, so as to spray two trees with a small distance.

Therefore, the agricultural plant protection unmanned aerial vehicle of the present embodiment further includes a boom extension mechanism 125. The control module 19 is communicatively connected to a boom extension mechanism 125, and the boom extension mechanism 125 adjusts the length of the boom 12 according to the spray length. Specifically, the boom 12 may include at least two rods and a boom extension mechanism 125, the two rods are connected through the boom extension mechanism 125, and the boom extension mechanism 125 may adjust the length of the boom 12. The two rod bodies can be oppositely sleeved and arranged, and the machine arm telescopic mechanism is telescopic between the two rod bodies, so that the total length of the two rod bodies is changed. The boom extension mechanism 125 may be a rack and pinion, a telescopic rod, or the like.

The angle adjusting mechanism is in signal connection with the control module 19. The angle adjustment mechanism adjusts the angle between the horn 12 and the hub 11 based on the spray angle. The angle adjustment mechanism has a drive member 172. The control module 19 is in control connection with the drive member 172. The control module 19 can control the rotation or extension of the driving member 172 to control the angle between the arm 12 and the hub 11.

Also, the control module 19 may control different nozzles 14. The agricultural plant protection unmanned aerial vehicle can automatically select the nozzle 14 at the corresponding position to work according to preset conditions. Or, the agricultural plant protection unmanned aerial vehicle 1 may select the nozzle 14 at the corresponding position to work according to the input information of the user, and the user selects the nozzle according to the current conditions. It is understood that the control module 19 may control the operation of the nozzles 14 by way of a water pump, control valve, etc.

Please refer to fig. 8, a method for controlling an agricultural plant protection unmanned aerial vehicle is also provided.

The control method of the agricultural plant protection unmanned aerial vehicle of the embodiment comprises the following steps:

and step S11, collecting the shape information of the object to be sprayed.

Specifically, the shape information includes the size of the space between two adjacent objects to be sprayed and the height of the objects to be sprayed. When the object to be sprayed is a tree, the collected form information can be the size of the space between two adjacent trees, the distance between the bottom branch and the top branch of the tree, the length information of the bottom branch and the top branch, the growth angle of the tree branches and the like. And determining the growth angle of the branches according to the included angle between the collected growth direction of the branches and the vertical direction.

And step S12, determining the spraying angle of the nozzle according to the form information.

According to the shape information of the tree, the branch growth angle of the tree can be obtained. The spray angle of the nozzle 14 is approximately equal to the growth of the branches. Therefore, the spraying angle of the nozzle 14 can be determined according to the growing angle of the branch.

And step S13, adjusting the included angle between the machine arm and the central body according to the spraying angle.

The adjustment of the spray angle of the nozzle 14 is achieved by the angle between the horn 12 and the central body 11. And the included angle between the horn 12 and the central body 11, i.e. the included angle between the horn 12 and the heading axis Z, is equal. Therefore, the spraying direction of the nozzle 14 can be sprayed along the growth direction of the tree branches only by adjusting the included angle between the machine arm 12 and the heading axis Z and keeping the spraying direction of the nozzle 14 approximately consistent with the growth angle of the tree branches.

In addition, referring to fig. 9, the method for controlling the agricultural plant protection unmanned aerial vehicle 1 further includes: and step S14, when the distance is smaller than the threshold value, determining the spraying length of the horn according to the form information, and adjusting the spraying length of the horn.

This threshold value can be the flight diameter size of agricultural plant protection unmanned aerial vehicle 1. And obtaining the distance between two adjacent trees according to the acquired morphological information. And determining the spraying length of the machine arm according to the distance.

When the interval between two trees is less than agricultural plant protection unmanned aerial vehicle 1's flight diameter, then agricultural plant protection unmanned aerial vehicle 1's horn 12 length is adjusted to reduce agricultural plant protection unmanned aerial vehicle 1's flight diameter, so that agricultural plant protection unmanned aerial vehicle 1 can fly and get into between two trees, implement the operation of spraying.

When the interval between two trees is greater than the flight diameter of agricultural plant protection unmanned aerial vehicle 1, then the horn 12 of agricultural plant protection unmanned aerial vehicle 1 sprays the operation with the biggest length of spraying.

In some embodiments, the nozzle 14 at the corresponding position is selected to perform the spraying operation according to the flight direction of the agricultural plant protection unmanned aerial vehicle 1 and the wind direction of the working environment, so as to prevent the mist sprayed from the nozzle 14 from dropping on the central body 11 and damaging the electronic devices on the central body 11. When the agricultural plant protection unmanned aerial vehicle 1 flies toward the head direction, or if the agricultural plant protection unmanned aerial vehicle 1 flies against the wind, the nozzle 14 in the tail direction is selected. When the agricultural plant protection unmanned aerial vehicle 1 flies toward the tail direction, or if the agricultural plant protection unmanned aerial vehicle 1 flies against the wind, the nozzle 14 in the head direction is selected. When the flight direction of the agricultural plant protection unmanned aerial vehicle 1 is up-down lifting flight, and the fog drops sprayed by the nozzles 14 are not affected by the flight direction and the wind direction, the nozzles 14 positioned in the head and tail directions can be selected for use.

In one embodiment, the nozzle 14 in the adaptive position is selected to perform spraying operation according to the flight direction of the agricultural plant protection unmanned aerial vehicle 1. For example, if the spraying penetration needs to be increased, when the agricultural plant protection unmanned aerial vehicle 1 flies toward the aircraft nose direction, the nozzle 14 in the aircraft nose direction is selected, so that the sprayed droplets are accelerated to be sprayed downward under the action of the airflow generated by the flying power device of the agricultural plant protection unmanned aerial vehicle 1. If in order to avoid that the fogdrop sprayed by the nozzle 14 is influenced by the air current, when the agricultural plant protection unmanned aerial vehicle 1 flies towards the tail direction, the nozzle 14 in the tail direction is selected, so that the sprayed fogdrop is influenced by the air current generated by the flight power device of the agricultural plant protection unmanned aerial vehicle 1.

In some embodiments, the nozzles 14 are selected to be suitable for spraying according to the wind direction of the working environment of the agricultural plant protection unmanned aerial vehicle 1, so as to reduce the error caused by the drift of the sprayed fog drops. For example, if the agricultural plant protection drone 1 is flying upwind, the nozzle 14 in the nose direction is selected. If the agricultural plant protection unmanned aerial vehicle 1 flies downwind, the nozzle 14 in the direction of the tail of the vehicle is selected.

In some embodiments, the nozzle 14 in the adaptive position is selected to perform the spraying operation according to the orientation of the agricultural plant protection unmanned aerial vehicle 1 compared with the operation area. For example, if the agricultural plant protection unmanned aerial vehicle 1 only needs to spray trees on one side, the agricultural plant protection unmanned aerial vehicle 1 only needs to open the nozzle 14 on the right side to work, and clockwise sprays along the border of the operation area of trees to avoid spraying too much to the outside of the operation area. Or, the agricultural plant protection unmanned aerial vehicle 1 only needs to open the left nozzle 14 to work and spray along the boundary of the operation area of the trees counterclockwise, so as to avoid excessive spraying to the outside of the operation area.

In some embodiments, the agricultural plant protection unmanned aerial vehicle 1 may automatically select the nozzle 14 at the corresponding position according to preset conditions. Alternatively, the agricultural plant protection unmanned aerial vehicle 1 may select the nozzle 14 at the corresponding position according to the input information of the user, and the user selects the nozzle according to the current conditions.

While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.