Massachusetts Institute of Technology

Christian Alexander Haughwout

Kerri Cahoy

James R Clark

Anantha P Chandrakasan

Ruonan Han

Paul Serra

Paula Do Vale Pereira

Derek C Barnes

Maxim Oleg Khatsenko

Femto-satellites are very small satellites that can be deployed in constellations from a larger mothership satellite for distributed measurement. They are too small to accommodate the GNSS receivers that many satellites use for navigation, but they can be located with an electromagnetic beam from the mothership satellite. The mothership satellite scans this beam across a constellation of femto-satellites. When the beam scans across a particular femto-satellite, the femto-satellite transmits an acknowledgement to the mothership satellite, e.g., by retroreflecting the beam or via a separate radio link. The beam can be modulated with commands for the femto-satellite, such as to make a measurement or transmit previously acquired data, as well with commands for determining the femto-satellite's location, such as a time stamp or beam pointing information. The femto-satellite can determine its location from the information modulated onto the beam or transmit the time stamp to the mothership satellite for localization.

Localizing, waking-up, and estimating direction of femto-satellites

A controllable shape memory alloy (SMA) hinge apparatus comprises multiple SMA elements to effect a first angle of rotation and a second angle of rotation between a first object and a second object. In one example, respective SMA elements are independently activated by Joule heating to rotate the first object and/or the second object. SMA elements undergo a three-dimensional transformation, and a pair of elements may undergo antagonistic transformations so as to provide for a multiple-use bidirectional non-continuous rotary actuator. SMA elements may be trained to achieve different angles of rotations between the objects (e.g., zero degrees and 90 degrees). In some examples, the first object may be a spacecraft (e.g., a satellite) and the second object may be a deployable structure (e.g., a robotic appendage, a deployable solar panel, a deployable aperture, a deployable mirror, a deployable radiator, and at least one actuator to steer an antenna dish).

Shape memory alloy (SMA) hinge apparatus, and systems and methods employing same

A beam steering system for a free-space laser communication system in a satellite includes a laser that emits a laser beam, a liquid lens assembly with at least one liquid lens to change the direction of the laser beam, and an amplifying optic to amplify the change in direction of the laser beam. The beam steering system may be used to steer a laser beam transmitted to another satellite or received from another satellite. In one example, a satellite may include two beam steering systems, disposed at opposing ends of a frame, where each steering system is configured to cover a hemisphere such that together, the steering systems can transmit and/or receive a laser beam over a 4&#x3c0; steradian sphere. The beam steering system may include a transmit feedback system and a reception system to monitor the direction and signal of the transmitted beam and the received beam, respectively.

Liquid-lens based optical steering system for free-space laser communication

Growing community of inventors

Clinton, CT, United States of America

Christian Alexander Haughwout