Structures and Machining
Leads:
Kutessa Garnett (Civil Engineering)
Hetav Patel (Aerospace Engineering)
Fernando Saca (Space Systems Engineering)
Members:
Andrew Bertino (Aerospace Engineering)
Kenyon Burke (Aerospace Engineering)
Subsytem Overview
The structures subsystem's job is to create a suitable bus for all of M-Cubed's components. The structure itself must hold all of its components safely during launch and in space. The structure has been designed under Cal Poly's CubeSat specification in order to fit in the P-POD (Poly Picosatellite Orbital Deployer), our interface with the rocket and our launcher. The structure also must handle physical interfaces between components, ensuring that any cables are routed correctly within the structure.
Assembly
The main structure is composed of six rectangular isogrid panels attached to four rails at each corner. The isogrid panels provide rigidity while being lower in mass than a solid panel. This reduction in mass allows a better medium through which is necessary for connection to solar panels and antennas. All panels, except the front panel, contain similar patterns. The front panel is modified to provide a circular opening for the camera lens. The rails to which these panels are attached will be hollowed out from the bottom face to reduce mass as well as providing a channel through which the power and electrical subsystem can access the spring-loaded plunger necessary to indicate M-Cubed’s release from the P-POD.
To be compatible with the P-POD, M-Cubed must be hard anodized and have a height of 113.5 mm to allow distance between different cubesats. Another requirement that was incorporated was the placement of the RBF (Remove Before Flight) pin. This pin must face the access panels on the side of the P-POD.
Thermal
To provide proper protection from radiation and heat fluxes, a passive thermal protection system consisting of proper insulation has been proposed. This insulation will consist of a layer of Kapton outside the panels, which will also act as an adhesive for the solar panels, and MLI inside the structure. Since solar panels will be covering most of the panels, the layer will be acting as additional insulation. Additional thermal covering will be used around the batteries, which are the most thermally sensitive components.
Machining
Since the M-Cubed structure is fabricated predominantly in-house, there is a need for a full-time machining team. The machining team works in the machine shop to make everything from aluminum rails, panels, battery mounts, and board mounts to delrin spacers. The entire structure for M-Cubed flight unit has been completed.
