FIXTURE AND METHOD FOR DETERMINING THE CENTER OF GRAVITY OF A REMOTE CONTROLLED AIRCRAFT

Abstract

A device for determining the center of gravity (CG) of a remote controlled aircraft includes a base member having a slotted track defined therein and a plurality of support platforms mounted on the base member. Each support platform of the plurality of support platforms is slidably positionable along the slotted track and each support platform may receive a digital CG sensor thereon. A plurality of leveling members is also mounted on the base member, with each leveling member of the plurality of leveling members being independently vertically translatable to adjust the orientation of the base member until the base member is level with the horizontal plane.

Claims

1. A device for determining the center of gravity (CG) of a remote controlled aircraft, the device comprising: a) a base member including a slotted track defined therein; b) a plurality of support platforms mounted on the base member, wherein each support platform of the plurality of support platforms is slidably positionable along the slotted track, and wherein each support platform is configured to receive a digital CG sensor thereon; and c) a plurality of leveling members mounted on the base member, wherein each leveling member of the plurality of leveling members is independently vertically translatable to adjust the orientation of the base member until the aircraft is level with the horizontal plane.

2. The device of claim 1 wherein the base member is generally T-shaped including a first arm arranged perpendicular to a second arm.

3. The device of claim 2 wherein each of the first arm and the second arm comprise either a t-slotted track or a t-slotted quad rail.

4. The device of claim 2 wherein the first arm is secured to the second arm through a cross lap joint.

5. The device of claim 1 wherein the slotted track includes reference indicia along the base member whereby the position of the plurality of support platforms is indexed.

6. The device of claim 1 further comprising a wing edge indicator mounted on the base member and slidably positionable along the slotted track.

7. A method for determining the center of gravity (CG) of a remote controlled aircraft, the method comprising: a) providing a CG measurement device including a base member having a slotted track defined therein and a plurality of support platforms mounted on the base member, wherein each support platform of the plurality of support platforms is slidably positionable along the slotted track; b) positioning a respective digital CG sensor on each support platform, wherein each respective digital CG sensor includes a mass scale to measure a mass of the aircraft at each respective digital CG sensor; c) placing a respective wheel of the aircraft on each respective digital CG sensor; d) measuring: i) a first distance between front and rear wheels of the aircraft; ii) a second distance from main wheels of the aircraft and a leading edge of each wing, wherein the second distance is subtracted from a manufacturer-provided CG location to yield a third distance; and e) calculating a CG location of the aircraft using each mass measurement recorded by each respective digital CG sensor, the first distance and the third distance.

8. The method of claim 7 further comprising: f) adjusting mass on the aircraft until the calculated CG is substantially equal to the manufacturer-provided CG location.

9. The method of claim 8 further comprising: a) leveling a wing of the aircraft with respect to a horizontal plane prior to measuring the first distance and the second distance.

10. The method of claim 7 further comprising: a) leveling a wing of the aircraft with respect to a horizontal plane prior to measuring the first distance and the second distance.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0009] FIG. 1A is a front perspective view of an exemplary aircraft equipped with tricycle landing gear positioned on an embodiment of a CG measuring device in accordance with the present invention;

[0010] FIG. 1B is a side perspective view of an exemplary aircraft equipped with bicycle landing gear positioned on the embodiment of a CG measuring device shown in FIG. 1;

[0011] FIG. 2 is perspective schematic view of an exemplary CG measuring device in accordance with an embodiment of the present invention;

[0012] FIGS. 2A and 2B are expanded views of the exemplary embodiment of a CG measuring device as shown in FIG. 2;

[0013] FIG. 3 is an exploded view of the exemplary embodiment of a CG measuring device shown in FIG. 2;

[0014] FIG. 3A is an expanded view of the exemplary embodiment of a CG measuring device as shown in FIG. 3;

[0015] FIG. 4 is a top plan view of the exemplary embodiment of a CG measuring device shown in FIG. 2;

[0016] FIG. 4A is an expanded view of the exemplary embodiment of a CG measuring device shown in FIG. 4; and

[0017] FIG. 5 is a side plan view of the exemplary embodiment of a CG measuring device shown in FIG. 2.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0018] This description is made for the purpose of illustrating the general principles of the invention and should not be taken in a limiting sense. Referring generally now to FIGS. 1A and 1B, in accordance with an aspect of the present invention, an exemplary embodiment of device 10 for determining the center of gravity (CG) of a remote controlled aircraft 12 is shown with wheels 14 of aircraft 12 positioned atop respective digital CG sensors 16, which are in turn mounted onto device 10. As can be seen in FIGS. 1A and 1B, device 10 may be suitable for use with either a plane having tricycle landing gear (FIG. 1A, aircraft 12a) or bicycle landing gear (FIG. 1B, taildragger aircraft 12b). By way of example and without limitation thereto, one exemplary digital CG sensor kit may be the CGPRO40 digital weight and balance meter available from XICOY Electronica SL, Canet de Mar, Spain.

[0019] With reference to FIGS. 2-5, device 10 may generally include a base member 18 having a slotted track 20 defined therein. By way of example and without limitation, base member 18 may be generally T-shaped including a first arm 22 arranged perpendicular to a second arm 24. Each of the first arm 22 and the second arm 24 may comprise either a t-slotted track or a t-slotted quad rail whose terminal ends may capped with an endcap 25. See FIGS. 2 and 2B. As shown in FIGS. 3 and 3A, first arm 22 and second arm 24 may include respective corresponding notches 22a, 24a which are configured to form a cross lap joint 26. As shown in FIGS. 1A and 1B, angle brackets 28 may also be included to reinforce cross lap joint 26 and ensure that first and second arms 22, 24 remain perpendicularly oriented to one another.

[0020] Referring again to FIGS. 2-5, device 10 may include a plurality of support platforms 30 mounted on base member 18. As shown most clearly in FIGS. 2A and 3, each support platform 30 may include a plate member 32 and a channeled member 34. Channeled members 34 are dimensioned to be received within slotted track 20 whereby each support platform 30 is selectively slidably positionable along first arm 22 and/or second arm 24. As shown in FIGS. 3, 3A and 4, first arm 22 and/or second arm 24 may also include reference indicia 23 thereon whereby the position of each of the plurality of support platforms 30 may be indexed and measured, as will be discussed in greater detail below.

[0021] With reference to FIGS. 2, 3 and 5, base member 18 may also have a plurality of leveling members 36 mounted on the bottom surface 38, 40 of respective first arm 22 and second arm 24. Each leveling member 36 is independently vertically translatable to adjust the orientation of the base member 18 until base member 18 is level with the horizontal plane. A wing edge indicator 42 may be mounted on the base member 18 (such as first arm 22) and may be slidably positionable along the slotted track 20, as will be described in greater detail below. In a further aspect of the invention, a vertically adjustable tail level adapter (not shown) may also be employed with bicycle landing gear aircraft 12b (FIG. 1B) to selectively raise the rear wheel 14r until wing 12w is parallel (level) to the horizontal plane.

[0022] In a further aspect of the present invention, an exemplary method for determining the center of gravity (CG) of a remote controlled aircraft 12 may include: a) providing a CG measurement device 10 including a base member 18 having a slotted track 20 defined therein and a plurality of support platforms 30 mounted on the base member, wherein each support platform 30 of the plurality of support platforms is slidably positionable along the slotted track 20; b) positioning a respective digital CG sensor 16 on each support platform 30, wherein each respective digital CG sensor 16 includes a mass scale to measure a mass of aircraft 12 at each respective digital CG sensor 16; c) placing a respective wheel 14 of the aircraft 12 on each respective digital CG sensor 16; d) measuring: i) a first distance D1 between front 14f and rear wheels 14r of the aircraft 12; ii) a second distance D2 from main wheels (e.g., 14r for a tricycle aircraft) of the aircraft 12 and a leading edge L of each wing 12w, wherein the second distance D2 is subtracted from a manufacturer-provided CG location (CGm) to yield a third distance D3; and e) calculating a CG location (CGc) of the aircraft using each mass measurement recorded by each respective digital CG sensor 16, the first distance D land the third distance D3. Mass on aircraft 12 may be adjusted (e.g., added, removed or relocated) until the calculated CGc is substantially equal to the manufacturer-provided CGm location. Once CGc and CGm are equal, aircraft 12 may be properly balanced, thereby improving flight performance. In a further aspect of the invention, the aircraft wings may be leveled with respect to the horizontal plane prior to measuring the first distance and the second distance.

[0023] The foregoing description of the preferred embodiment of the invention has been presented for the purpose of illustration and description. It is not intended to be exhaustive nor is it intended to limit the invention to the precise form disclosed. It will be apparent to those skilled in the art that the disclosed embodiments may be modified in light of the above teachings. The embodiments described are chosen to provide an illustration of principles of the invention and its practical application to enable thereby one of ordinary skill in the art to utilize the invention in various embodiments and with various modifications as are suited to the particular use contemplated. Therefore, the foregoing description is to be considered exemplary, rather than limiting, and the true scope of the invention is that described in the following claims.