23 research outputs found

    Rock Gripper for Sampling, Mobility, Anchoring, and Manipulation

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    A new gripper mechanism can be used as an end effector for a long arm that reaches out from a nearby spacecraft for a touch-and-go type of mission. The gripper would stabilize the arm and allow samples to be collected and in situ science to be done from a fixed platform. In the long term, this style of gripper could even be used as handholds for astronauts trying to move about on/near small asteroids. The prototype developed has demonstrated a 120 N gripping force, and improvements continue to be made

    Recipient of the 2018 Alumni Distinguished Leadership Award

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    Dr. Parness is Group Leader, Extreme Environments Robots at NASA\u27s Jet Propulsion Laboratory where iterative design principles and rapid prototyping are embraced to quickly invent and develop robotic systems for mobility and manipulation. Dr. Parness earned a Bachelor of Science in Mechanical Engineering and Creative Writing from Massachusetts Institute of Technology and a PhD in Mechanical Engineering from Stanford University

    Comparison of heat sink and fan combinations and thermal electric coolers for use in the Mars Gravity Biosatellite

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    Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2004.Includes bibliographical references.An experiment was conducted to help compare possible cooling methods for the payload module of the Mars Gravity Biosatellite. The Satellite will be launched into space with 15 mice on board and rotated to create a 0.38g centrifugal acceleration, the acceleration due to gravity on Mars. The mission will last 5 weeks and take valuable data on mammal's responses to extended periods of time in reduced gravity. Because of a large heat shield needed for reentering the Earth's atmosphere, the payload module is nearly perfectly insulated. It is therefore necessary to actively transport heat out of the capsule and radiate it off into space. A thermal electric cooler and a heat sink and fan combination were compared in this experiment for that purpose, using a Styrofoam cooler as a model payload. It was found that the fan and heat sink combination was more efficient than the thermal electric cooler. The coefficient of performances of the respective cooling elements was found to be 5.89 for the fan and heat sink while only 1.67 for the thermal electric cooler. However, it was also observed that the thermal electric cooler, while less efficient, could transport much more heat than the fan and heat sink alone, 26.4 Watts compared to 9.73 Watts in the experimental set up. It has been recommended that a combination of a fan and heat sink be used in the payload module of the satellite.by Aaron J. Parness.S.B

    Robotic Ankle for Omnidirectional Rock Anchors

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    Future robotic exploration of near-Earth asteroids and the vertical and inverted rock walls of lava caves and cliff faces on Mars and other planetary bodies would require a method of gripping their rocky surfaces to allow mobility without gravitational assistance. In order to successfully navigate this terrain and drill for samples, the grippers must be able to produce anchoring forces in excess of 100 N. Additionally, the grippers must be able to support the inertial forces of a moving robot, as well gravitational forces for demonstrations on Earth. One possible solution would be to use microspine arrays to anchor to rock surfaces and provide the necessary load-bearing abilities for robotic exploration of asteroids. Microspine arrays comprise dozens of small steel hooks supported on individual suspensions. When these arrays are dragged along a rock surface, the steel hooks engage with asperities and holes on the surface. The suspensions allow for individual hooks to engage with asperities while the remaining hooks continue to drag along the surface. This ensures that the maximum possible number of hooks engage with the surface, thereby increasing the load-bearing abilities of the gripper. Using the microspine array grippers described above as the end-effectors of a robot would allow it to traverse terrain previously unreachable by traditional wheeled robots. Furthermore, microspine-gripping robots that can perch on cliffs or rocky walls could enable a new class of persistent surveillance devices for military applications. In order to interface these microspine grippers with a legged robot, an ankle is needed that can robotically actuate the gripper, as well as allow it to conform to the large-scale irregularities in the rock. The anchor serves three main purposes: deploy and release the anchor, conform to roughness or misalignment with the surface, and cancel out any moments about the anchor that could cause unintentional detachment. The ankle design contains a rotary DC motor that can drag the microspine arrays across the surface to engage them with asperities, as well as a linear actuator to disengage the hooks from the surface. Additionally, the ankle allows the gripper to rotate freely about all three axes so that when the robot takes a step, the gripper may optimally orient itself with respect to the wall or ground. Finally, the ankle contains some minimal elasticity, so that between steps, the gripper returns to a default position that is roughly parallel to the wall

    Terrain Traversing Device Having a Wheel with Microhooks

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    A terrain traversing device is described. The device includes an annular rotor element with a plurality of co-planar microspine hooks arranged on the periphery of the annular rotor element. Each microspine hook has an independently flexible suspension configuration that permits the microspine hook to initially engage an irregularity in a terrain surface at a preset initial engagement angle and subsequently engage the irregularity with a continuously varying engagement angle when the annular rotor element is rotated for urging the terrain traversing device to traverse a terrain surface. Improvements related to the design, fabrication and use of the microspine hooks in the device are also described

    Stick shift

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    Thesis (S.B. in Creative Writing)--Massachusetts Institute of Technology, Dept. of Humanities, Program in Writing and Humanistic Studies, 2004.Stick Shift is a novel that has undergone several rounds of significant revision. Scott, the book's main character, is a sarcastic American who travels to England to move in with an ex-girlfriend. He experiences all of the obstacles involved in moving to a new country, leaving his home, and settling down with a woman in a comic sequence told in seven chapters.The introduction to this piece outlines my history as a writer, primarily focusing on my development at MIT. The thesis project is discussed and followed from its initial seed all the way through to its current state.by Aaron Parness.S.B.in Creative Writin

    Systems and Methods for Implementing Flexible Members Including Integrated Tools Made from Metallic Glass-Based Materials

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    Systems and methods in accordance with embodiments of the invention implement flexible members that include integrated tools made from metallic glass-based materials. In one embodiment, a structure includes: a flexible member characterized by an elongated geometry and an integrated tool disposed at one end of the elongated geometry; where the flexible member includes a metallic glass-based material

    Microgravity Drill and Anchor System

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    This work is a method to drill into a rock surface regardless of the gravitational field or orientation. The required weight-on-bit (WOB) is supplied by a self-contained anchoring mechanism. The system includes a rotary percussive coring drill, forming a complete sampling instrument usable by robot or human. This method of in situ sample acquisition using micro - spine anchoring technology enables several NASA mission concepts not currently possible with existing technology, including sampling from consolidated rock on asteroids, providing a bolt network for astronauts visiting a near-Earth asteroid, and sampling from the ceilings or vertical walls of lava tubes and cliff faces on Mars. One of the most fundamental parameters of drilling is the WOB; essentially, the load applied to the bit that allows it to cut, creating a reaction force normal to the surface. In every drilling application, there is a minimum WOB that must be maintained for the system to function properly. In microgravity (asteroids and comets), even a small WOB could not be supported conventionally by the weight of the robot or astronaut. An anchoring mechanism would be needed to resist the reactions, or the robot or astronaut would push themselves off the surface and into space. The ability of the system to anchor itself to a surface creates potential applications that reach beyond use in low gravity. The use of these anchoring mechanisms as end effectors on climbing robots has the potential of vastly expanding the scope of what is considered accessible terrain. Further, because the drill is supported by its own anchor rather than by a robotic arm, the workspace is not constrained by the reach of such an arm. Yet, if the drill is on a robotic arm, it has the benefit of not reflecting the forces of drilling back to the arm s joints. Combining the drill with the anchoring feet will create a highly mobile, highly stable, and highly reliable system. The drilling system s anchor uses hundreds of microspine toes that independently find holes and ledges on a rock to create an anchor. Once the system is anchored, a linear translation mechanism moves the drill axially into the surface while maintaining the proper WOB. The linear translation mechanism is composed of a ball screw and stepper motor that can translate a carriage with high precision and applied load. The carriage slides along rails using self-aligning linear bearings that correct any axial misalignment caused by bending and torsion. The carriage then compresses a series of springs that simultaneously transmit the load to the drill along the bit axis and act as a suspension that compensates for the vibration caused by percussive drilling. The drill is a compacted, modified version of an off-the-shelf rotary percussive drill, which uses a custom carbide-tipped coring bit. By using rotary percussive drilling, the drill time is greatly reduced. The percussive action fractures the rock debris, which is removed during rotation. The final result is a 0.75-in. (.1.9- cm) diameter hole and a preserved 0.5- in. (.1.3-cm) diameter rock core. This work extends microspine technology, making it applicable to astronaut missions to asteroids and a host of robotic sampling concepts. At the time of this reporting, it is the first instrument to be demonstrated using microspine anchors, and is the first self-contained drill/anchor system to be demonstrated that is capable of drilling in inverted configurations and would be capable of drilling in microgravity

    Systems and Methods for Gravity-Independent Gripping and Drilling

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    Systems and methods for gravity independent gripping and drilling are described. The gripping device can also comprise a drill or sampling devices for drilling and/or sampling in microgravity environments, or on vertical or inverted surfaces in environments where gravity is present. A robotic system can be connected with the gripping and drilling devices via an ankle interface adapted to distribute the forces realized from the robotic system
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