Telescoping support structure
The technology relates to a telescoping support structure which can be suspended between two objects. The telescoping support structure uses projections between adjacent tubular sections in order to prevent the adjacent tubular sections from falling away from one another. Although the telescoping support structure may be utilized in various different environments and circumstances, it may be of particular usefulness in the field of high-altitude ballooning. For instance, when used in a balloon system, the telescoping support structure may be suspended between two objects such as an upper payload structure and a lower payload structure. As another example, the telescoping support structure may be suspended between a balloon envelope and a payload which, in some examples, may include an upper and a lower payload structure.
1. A system comprising:
a telescoping support structure including:
a first terminal tubular section including a first terminal feature at a first end of the first terminal tubular section and an interior projection at a second end of the first terminal tubular section, the first end of the first terminal tubular section being opposite of the second end of the first terminal tubular section, and the first terminal feature including a spool of cable;
a second terminal tubular section including a second terminal feature at a first end of the second terminal tubular section and an exterior projection at a second end of the second terminal tubular section, the first end of the second terminal tubular section being opposite of the second end of the second terminal tubular section, and the second terminal feature being connected to the cable of the spool of cable; and
one or more intermediate tubular sections arranged between the first terminal tubular section and the second terminal tubular section, each given one of the one or more intermediate tubular sections including a respective first projection on an exterior surface of the given one and a respective second projection on an interior surface of the given one, and wherein the interior projection is configured to engage with a respective first projection of one of the one or more intermediate tubular sections and the exterior projection is configured to engage with a respective second projection of the one or more intermediate tubular sections.
2. The system of claim 1 , further comprising a balloon envelope and a payload, wherein the telescoping support structure is arranged between the balloon envelope and the payload.
3. The system of claim 1 , further comprising a balloon envelope and a payload including upper payload structure and a lower payload structure, wherein the telescoping support structure is arranged between the upper payload structure and the lower payload structure.
4. The system of claim 1 , wherein each respective first projection is configured in a wedge-shape having a predetermined angle to facilitate engagement of that first projection with another projection.
5. The system of claim 1 , wherein each respective second projection is configured in a wedge-shape having a predetermined angle to facilitate engagement of that second projection with another projection.
6. The system of claim 1 , wherein the respective first projection of the given one is formed from a same material as the given one.
7. The system of claim 1 , wherein the respective first projection of the given one is integral to the exterior surface of the given one.
8. The system of claim 1 , wherein the respective first projection of the given one is attached to the exterior surface of the given one using an epoxy material.
9. The system of claim 1 , wherein the respective second projection of the given one is integral to the interior surface of the given one.
10. The system of claim 1 , wherein the respective second projection of the given one is attached to the interior surface of the given one using an epoxy material.
11. The system of claim 1 , wherein at least one of the one or more intermediate tubular sections includes a flexure section configured to absorb bending stresses between the first terminal tubular section and the second terminal tubular section.
12. The system of claim 1 , wherein the respective second projection of the given one includes a tooth structure configured to limit rotation of an adjacent tubular section when the telescoping support structure is in a fully deployed condition.
13. The system of claim 1 , wherein the first terminal feature also includes a damper mechanism configured to limit rotation of the cable and thereby limit release of the cable when the telescoping support structure is being deployed.
14. The system of claim 13 , wherein the damper mechanism is a passive damper which produces torque in response to rotation of the spool.
15. The system of claim 13 , wherein the damper mechanism is an active damper which includes a motor.
16. The system of claim 13 , wherein the first terminal feature also includes a restraint device configured to restrain at least some of the cable on the spool when the telescoping support structure is in a stowed condition.
17. The system of claim 16 , wherein the restraint device also includes a wire configured to restrain at least some of the cable on the spool when the telescoping support structure is in the stowed condition.
18. The system of claim 17 , wherein the restraint device also includes an activation device configured, when activated, to cut the wire and allow the spool to release the at least some of the cable from the spool when the telescoping support structure is being deployed.
19. The system of claim 18 , further comprising a balloon wherein the activation device is configured to be activated when the balloon reaches a predetermined altitude.