The present disclosure relates to unmanned aerial vehicles with improved lift and stability characteristics.
Most unmanned aerial vehicles (UAVs) having a small multirotor design have flat or straight out motor arms attached to a center plate, in the range of 200 mm to 400 mm in length. This design causes stress on the bottom mounting plate when carrying loads, often rendering the structural strength weak, and most times touchy on the controls.
The present disclosure provides motor arm holders configured such that when inserted into its corresponding arm holder on the central hub or holder, the motor arm holders are tilted at an angle between 6 to 10 degrees angle upwards. This drops the entire machine relative to the central hub making the UAV unit more “bottom heavy”, thus creating a pendulum effect, which is more stable in flight.
An embodiment disclosed herein includes an unmanned aerial vehicle, comprising:
a) a landing gear including a support platform having opposed sides and a pair of landing gear legs descending from each of said opposed sides;
b) a housing and a support hub located therein;
c) a selected number of motor support arm holders evenly distributed about a periphery of said support hub;
d) each of said selected number of motor support arm holders having a proximal end portion of a corresponding motor support arm locked therein, said motor support arm holders being configured to lock the proximal end portion of the motor support arm such that the each motor support arm is inclined upwardly from horizontal by an angle in a range from about 6 to 10 degrees;
e) each motor support arm having a distal end and having a motor holder affixed thereto, and each motor holder having a propeller motor locked therein and each propeller motor having a propeller attached thereto;
f) an electronic control circuit array mounted on top of said top center plate;
g) a quick release utility plate releasably attached to, and spaced below, said bottom center plate, said quick release utility plate configured to releasably receive instrumentation for transportation by the unmanned aerial vehicle, said quick release utility plate being attached to said support platform;
h) said housing including a top canopy for enclosing and covering said electronic control circuit array and said hub which is releasably secured to said support platform; and
i) a space between said quick release utility plate and said bottom center plate configured to be a battery compartment and to receive therein one or two batteries electrically connected to said propeller motors and said electronic circuit array.
The support hub may include a top center plate and bottom center plate spaced apart and bolted together, and wherein said selected number of motor support arm holders evenly distributed about a periphery of said support hub are sandwiched between, and secured to, said top center plate and said bottom center plate.
Each motor support arm may be inclined upwardly from horizontal by an angle of about 8 degrees.
The motor support arms may be hollow having a hollow interior, and the motor holders may include a port located below said propeller motor which is aligned with the hollow interior of the motor support arm so that air from propeller wash is forced through the port down the hollow interior into an interior of the support hub. The motor support arms may be positioned to direct the air towards the electronic circuit array for air cooling the electronic circuit array.
The motor holder may include a stabilizer fin extending below a bottom of the motor holder. This stabilizer fin may be generally triangular in shape and positioned on the bottom of the propeller motor holder so that air from the propeller wash is forced past said stabilizer fin thereby acting to aid in stabilizing the unmanned aerial vehicle in flight.
In an embodiment, the battery compartment may be configured to receive one battery inserted from a side of the unmanned aerial vehicle with the one rectangular battery being centered in the battery compartment.
In another embodiment the battery compartment may configured to receive two batteries inserted from a front of the unmanned aerial vehicle with the two batteries being centered in the battery compartment.
The selected number of motor arm support holders may be any one of four, (4), six (6), and eight (8), and including a corresponding number of support arms mounted symmetrically around the hub.
The motor support arm holders may include a two (2) piece clamp including two (2) clamp sections, which upon being assembled together, between the top center plate and the bottom center plate, has an interior to receive therein the proximal end of the motor support arm, and upon being bolted together locks the motor support arm in place.
The motor support arm holders and associated motor support arms clamped therein may include a locking mechanism configured to prevent rotation of the motor support arm with respect to the motor support arm holder.
In one embodiment this locking mechanism may include a stud located on an inner surface of at least one of the clamp sections, and the proximal end of said motor support arm clamped between said two clamp sections including a hole having a size sufficiently large to receive the stud therein.
In another embodiment this locking mechanism may include a stud located on the proximal end of the motor support arm and one of the two clamp sections including a hole having a size sufficiently large to receive the stud therein.
In an embodiment each motor holder may include a two (2) piece clamp including two (2) clamp sections, which upon being assembled together, has an interior to receive therein the distal end of the motor support arm, and upon being bolted together locks the motor holder to the motor arm. A top clamp section of the two clamp sections may include a receptacle to receive therein the propeller motor, and a bottom clamp section of the two clamp sections may include a stabilizer fin integrally formed therewith on a bottom surface of the bottom clamp section. In this embodiment the motor holder and associated distal end of the motor support arm clamped therein may include a locking mechanism configured to prevent rotation of the motor holder with respect to the motor support arm. In an embodiment this locking mechanism may include a stud located on an inner surface of at least one of the clamp sections, and the distal end of the motor support arm clamped between the two clamp sections includes a hole having a size sufficiently large to receive the stud therein. In another embodiment this locking mechanism may include a stud located on the distal end of the motor support arm and one of the two clamp sections includes a hole having a size sufficiently large to receive the stud therein.
In an embodiment the motor arm holders and the motor support arms may be configured such that each motor support arm is moveable in the motor arm holder between at least two positions and can be locked in each position to provide at least two pre-set lengths of the motor support arm with respect to the hub. In this embodiment the motor arm holders may include a two (2) piece clamp may include two (2) clamp sections, which upon being assembled together, has an interior to receive therein the proximal end of the motor support arm, and upon being bolted together locks the motor arm in place.
In an alternative embodiment the motor arm holders and associated motor support arms clamped therein may include a locking mechanism configured to lock the motor support arms in the at least two positions with respect to the motor support arm holders, and to prevent rotation of the motor support arm with respect to the motor support arm holder when locked in each of the at least two positions. This locking mechanism may include a stud located on an inner surface of at least one of the clamp sections, and the proximal end of the motor support arm clamped between the two clamp sections including at least two holes spaced apart having a size sufficiently large to receive said stud therein, and wherein in at least a first of the at least two positions the stud is inserted through a first hole of two holes, and in a second of the at least two positions the stud is inserted through a second hole of the two holes. The locking mechanism may include at least two spaced studs located on the proximal end of the motor support arm and one of the two clamp sections including hole having a size sufficiently large to receive each stud therein.
The unmanned aerial vehicle may be configured such that the distal end of the motor support arms are above a top surface of the canopy such that in the event the unmanned aerial vehicle is inverted upside down on the ground it rests on the propellers and not the top surface of the canopy thereby providing protection for the electronic array.
The selected number of motor arm support holders may be six (6), and including six (6) corresponding support arms mounted symmetrically around the hub.
The support platform may include a support plate mounted on spaced beams oriented at about 90 degrees to a planar surface of the support plate, each end of each of the spaced beams have a hole extending therethrough, and including O-rings mounted in the holes, and including a first and second tubes mounted on the support platform at opposed sides thereof with the tubes extending through corresponding ends of the spaced beams such that the support plate is slidable back and forth towards the front and back of the support platform such that when a load is attached to the support plate its center of gravity can be adjusted.
The quick release universal adapter plate may include a pair of spaced holes located at side edges of the utility plate, and wherein the support platform includes a pair of spaced plates located on the side edges of the support platform each having two spaced holes extending therethrough in registration with corresponding holes in the quick release utility plate which are used to attach the universal adapter plate to the support platform.
There is disclosed herein an unmanned aerial vehicle kit, comprising:
a) a landing gear including a support platform having opposed sides and a pair of landing gear legs descending from each of said opposed sides;
b) four (4), six (6) and eight (8) motor support arms;
c) support hubs for each of said four (4), six (6) and eight (8) motor support arms, each support hub including support arm holders evenly distributed about a periphery of said support hub;
d) each of said motor support arm holders having a proximal end portion of a corresponding motor support arm locked therein, said motor support arm holders being configured to lock the proximal end portion of the motor support arm such that the each motor support arm is inclined upwardly from horizontal by an angle in a range from about 6 to 10 degrees;
e) each motor support arm having a distal end and having a motor holder affixed thereto, and each motor holder having a propeller motor locked therein and each propeller motor having a propeller attached thereto;
f) an electronic control circuit array mounted on top of said top center plate;
g) a quick release universal plate releasably attached to, and spaced below, said bottom center plate, said quick release utility plate configured to releasably receive instrumentation for transportation by the unmanned aerial vehicle, said quick release universal plate being attached to said support platform;
h) a housing including a top canopy for enclosing and covering said electronic control circuit array and said hubs which is releasably secured to said support platform; and
i) a space between said quick release utility plate and said bottom center plate configured to be a battery compartment and to receive therein one or two batteries electrically connected to said propeller motors and said electronic circuit array.
A further understanding of the functional and advantageous aspects of the present disclosure can be realized by reference to the following detailed description and drawings.
Embodiments disclosed herein will be more fully understood from the following detailed description thereof taken in connection with the accompanying drawings, which form a part of this application, and in which:
Various embodiments and aspects of the disclosure will be described with reference to details discussed below. The following description and drawings are illustrative of the disclosure and are not to be construed as limiting the disclosure. Numerous specific details are described to provide a thorough understanding of various embodiments of the present disclosure. However, in certain instances, well-known or conventional details are not described in order to provide a concise discussion of embodiments of the present disclosure.
As used herein, the terms “comprises” and “comprising” are to be construed as being inclusive and open ended, and not exclusive. Specifically, when used in the specification and claims, the terms “comprises” and “comprising” and variations thereof mean the specified features, steps or components are included. These terms are not to be interpreted to exclude the presence of other features, steps or components.
As used herein, the term “exemplary” means “serving as an example, instance, or illustration,” and should not be construed as preferred or advantageous over other configurations disclosed herein.
As used herein, the terms “about” and “approximately” are meant to cover variations that may exist in the upper and lower limits of the ranges of values, such as variations in properties, parameters, and dimensions.
Mounted on support platform 12 is utility housing 16. Six (6) motor support arms 20 extend outwardly from housing 16 and mounted on the distal ends of motor support arms 20 are propeller motors 34. Propellers 22 are each coupled to propeller motors 34 which in turn is seated in a two piece motor holder 36. The lower portion of the two piece motor holder 36 has a small triangular fin 38 just below the motor area. This fin 38 serves as a stabilizer on the “yaw” axis (rotation of the unit left or right). This fin 38 is very advantageous when the UAV is in wind conditions in that it helps to maintaining the UAV 10 pointing in the right direction as much as possible. The propeller wash forcing air downwards re-enforces the effect of these fins 38.
Another advantage of the motor support arms 20 being angled upwardly is that the distal ends of the motor support arms 20 are above a top surface of the canopy 56 such that in the event the unmanned aerial vehicle 10 is inverted upside down on the ground it rests on the propellers 22 and not on the top surface of the canopy 56, see
Referring again to
Hub 32 is secured to support platform 12 when the UAV 10 is assembled. Utility housing 16 includes a circuit array 40 which includes all the various circuit boards required for operation of the UAV including such as balance controllers, motor controllers for controlling propeller motors 34, flight and navigation control board(s) and global positioning system (GPS) circuits, communication circuits to allow an operator on the ground to control all aspects of UAV 10. A GPS shield 50 is mounted over top of circuit array 40 and secured and hub 32 via holes 52 aligned with spacers 48 and aligned with corresponding holes located in hub 32. A GPS antenna 54 is mounted on top of GPS shield 50 which is connected to the GPS circuits located in circuit array 40. A cover dome or canopy 56 is secured to the above-mentioned holes in top center plate 120 in hub 32 by bolts extending through holes 52 and spacers 48. In an alternative embodiment canopy 56 may be attached directly to top center plate 120 of hub 32 by means of legs used specifically to attach the canopy 56 directly to the top center plate 120, in order to reduce vibration. The use of legs to connect the canopy 56 directly to the top center plate 120 is advantageous since there would be no contact between the canopy 56 and GPS shield 50, thereby reducing the chances of vibration. This would provide further protection for the various internal processor/circuitry and the hub 32.
Referring to
Referring again to
As can be more clearly seen in
It will be understood that the UAV 10 may be produced with several motor support arms 20 of varying length with the same two (2) holes 72 and 72 so that UAVs with different length propeller arms may be configured. More than one motor support arm 20 is useful because with the limited interior dimensions of hub 32 only two extension lengths of motor support arms 20 by the two holes 72 and 74 are really feasible to maintain the structural integrity of the assembled UAV, thus multiple lengths of motor support arms 20 gives a wider range of propeller arm extension.
An advantage of this embodiment over UAV's that have telescoping motor arms is that telescoping motor arms are more prone to flexing, while the present design of multiple locking holes in the motor support arms 20 which allows them to be locked at different lengths with respect to hub 32 does not adversely affect the structural strength of the arm.
Conventional multirotor UAVs can have four (4), six (6), or eight (8) motor arms, made of a variety of materials, most of which are of fixed length while some designs have folding motor arms to collapse the UAV for storage. This type of design limits the size of props that can be used on the platform. In the present UAV 10, motor support arms 20 have an adjustable extension length relative to the hub to give greater choice for arm length.
Thus, UAV 10 may be sold disassembled in a kit form with four (4), six (6) or eight (8) motor support arms 20 and associated propeller motors 34 and motor holders 36. Each kit may include three support hubs 32, one configured with four holders 106, one with six (6) holders 106 and one with eight (8) holders 106 evenly distributed about the periphery of the associated hub 32. This allows the user/operator the flexibility to configure the UAV 10 depending on load to be carried, flight times etc.
UAV 10 shown in the Figures has six (6) rotors 22 with associated arms 20 and motors 34. It will be appreciated however that UAV's with tilted support arms 20 could be made with 4, 6 or 8 motor support arms 20. In this case the motor support arms 20, motor mounts 36 and the arm holders 106 would have the same design, with the only difference being the center plates 120 and 122 would be different to accommodate the different number of arms 20. Similarly, depending on the number of motors the circuit array 40 would change due to the different number of motors 36 being used and electronics associate with each motor 36.
An advantage of this design is that it allows the use of propellers of different diameter, for example, non-limiting examples include the option of 9″, 10′″, 11″ or 12″ propellers. When shorter motor support arms 20 are used then the smaller props would be used in conjunction therewith, so that it would carry less payload, and thus less stress on the propeller motors 34 and hence longer flight times. Conversely when longer motor support arms 20 are used for bigger propellers, the UAV 10 will be able to carry more payload but for less flight time.
A current problem with the multirotor UAVs is how to supply enough power to the system in an efficient way and to allow for ease of a user in changing power packs and not throwing the center of gravity (CG) out. Most systems on the market today have to mount the batteries on the bottom of the UAV, which puts them in the way of camera mounts, in the front or rear, rendering the UAV unstable and gyros are constantly engaged to keep the flying platform level or on top, making the unit top heavy and creating a magnetic charge around the GPS system.
UAV 10 is provided with an adaptor plate 136, best seen in
In an non-limiting embodiment, adaptor plate 136 is cut out of Phenolic G10 aerospace material, offering hard density, low static conductivity part and has grooves to insert belts, or Velcro straps and slots for inserting bolts, giving the user/operator of UAV 10 the options to attach a variety of accessories they may be using to adapter plate 136. A Hex tool is supplied with the kit which fits the screws that come with the base assembly.
Referring to
Those skilled in the art will appreciate that supplying power to all the various components, motors, circuits, sensors etc. puts a strain on the UAV battery. In the present system, referring again to
Felt pads, (not shown) may be packed between the two batteries 58 (
These two battery storage configurations always centers the one (1) battery 58 when only one is used (
While the Applicant's teachings described herein are in conjunction with various embodiments for illustrative purposes, it is not intended that the applicant's teachings be limited to such embodiments. On the contrary, the applicant's teachings described and illustrated herein encompass various alternatives, modifications, and equivalents, without departing from the embodiments, the general scope of which is defined in the appended claims.
Except to the extent necessary or inherent in the processes themselves, no particular order to steps or stages of methods or processes described in this disclosure is intended or implied. In many cases the order of process steps may be varied without changing the purpose, effect, or import of the methods described.
Number | Date | Country | |
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62084845 | Nov 2014 | US |