Search Results

The MX-2 neutral buoyancy space suit analogue has been designed and developed at the University of Maryland to facilitate analysis of space suit components and assessment of the benefits of advanced space suit technologies, The MX-2 replicates the salient features of microgravity pressure suits, including the induced joint torques, visual, auditory and thermal environments, and microgravity through the use of neutral buoyancy simulation. In this paper, design upgrades and recent operations of the suit are outlined, including many experiments and tests of advanced space suit technologies, This paper focuses on the work done using the MX-2 to implement and investigate various advanced controls and displays within the suit, to enhance crewmember situational awareness and effectiveness, and enable human-robotic interaction.

This paper describes a unique concept for donning and doffing a spacesuit from a pressurized rover or habitat, which merges three independent concepts: suitports, neck-entry EVA suits, and the Morphing Upper Torso. The union of these concepts creates a novel and exciting suit and suitport system architecture, with many potential benefits over traditional suitport systems. To develop this concept, a neck-entry Morphing Upper Torso experimental model has been designed and fabricated, and systems level design studies have been performed, including visualization with the aid of CAD models of the neck-entry suitport on a small pressurized rover and a lunar habitat. As well, a donning test-station has been developed and used for experiments in 1-G, simulated microgravity and simulated partial gravity.

There has recently been an increasing focus on humans working cooperatively with robotic systems in space exploration and operations. Considerable work has been performed on distributed architectures to enable such interaction. The research described here looks at the human-robot interaction from the EVA astronaut's perspective, describing a first generation human-machine interface implemented and tested on an existing experimental spacesuit analog, the MX-2. The ultimate goal is to enable EVA astronauts to operate more independently of remote operators and work effectively with autonomous and teleoperated robots. The current system integrates speech interaction and visual interfaces as a first step towards this goal.

The research discussed in this paper demonstrates further advancements in the concept of a Morphing Upper Torso, which incorporates robotic elements within the pressure suit design to enable a resizable, highly mobile and easy to donn/doff spacesuit. A full scale experimental model has been made, which accompanies several analytical models. The Jacobian matrix for the robotic system, which multiplies the total twist vector of the system to yield the vector of actuator velocities, is derived. This dynamic analysis enables quantification of the dynamic actuator requirements, given demanded trajectories of the rings. A motion capture pilot study was done to develop a methodology to obtain measurements of suit movement and hence the ring trajectories. Subjects performed various tasks that a suited astronaut may perform on a planetary surface, while wearing a torso mockup within the motion capture system.

Extensive prior research at the University of Maryland Space Systems Laboratory has identified significant operational advantages to high levels of integration between EVA crew and dexterous robotics. Crew performance on recent Hubble Space Telescope repair missions was broken down into task primitives, and evaluated for the impact of dexterous robotics in direct support of extravehicular activity. Results demonstrate that direct EVA-robotic cooperation can increase human performance in satellite servicing tasks by factors ranging from at least 60% (for highly complex and dexterous servicing tasks) to as much as 400% for more simple activities with greater levels of planned orbital replacement unit (ORU) interchange. This paper details experimental and analytical investigations of differing approaches to adding dexterous robotic capabilities to the EVA work site, via increasingly direct integration of robotics into the space suit system itself.

The next generation of pressure suits must enable large-scale planetary Extra-Vehicular Activities (EVA). Astronauts exploring the moon and Mars will be required to walk many kilometers, carry large loads, perform intricate experiments, and extract geological samples. Advanced pressure suit architectures must be developed to allow astronauts to perform these and other tasks simply and effectively. The research developed here demonstrates integration of robotics technology into pressure suit design. The concept of a robotically augmented pressure suit for planetary exploration has been developed through the use of analytical and experimental investigations. Two unique torso configurations are examined, including a Soft/Hard Upper Torso with individually adjustable bearings, as well as advances in Morphing Upper Torso research, in which an all-soft torso is analyzed as a system of interconnected parallel manipulators.

The fit of a spacesuit has been identified as a crucial factor that will determine its usability. Therefore, because one-size-fits-all spacesuits seldom fit any wearer well, and because individually tailored spacesuits are costly, the University of Maryland has conducted research into a resizable Extravehicular Activity (EVA) suit. This resizing is accomplished through a series of cable-driven parallel manipulators, which are used to adjust the distance between plates and rings built into a soft space suit. These actuators, as well as enabling passive suit resizing, could be used to actively assist the astronaut's motion, decreasing the torques that must be applied for movement in a pressurized suit. This paper details the development and testing of an arm prototype, which is used to better understand the dynamics of a more complex torso-limb system.

A fully operational space suit analogue for use in a neutral buoyancy environment has been developed and tested by the University of Maryland’s Space Systems Laboratory. Repeated manned operations in the Neutral Buoyancy Research Facility have shown the MX-2 suit analogue to be a realistic simulation of operational EVA pressure suits. The suit is routinely used for EVA simulation, providing reasonable joint restrictions, work envelopes, and visual and audio environments comparable to those of current EVA suits. Improved gloves and boots, communications carrier assembly, in-suit drink bag and harness system have furthered the semblance to EVA. Advanced resizing and ballasting systems have enabled subjects ranging in height from 5′8″ to 6′3″ and within a range of 120 lbs to obtain experience in the suit. Furthermore, integral suit instrumentation facilitates monitoring and collection of critical data on both the suit and the subject.

The University of Maryland Space Systems Laboratory and ILC Dover LP have developed a novel concept: a soft pressure garment that can be dynamically reconfigured to tailor its shape properties to the wearer and the desired task set. This underlying concept has been applied to the upper torso of a rear entry suit, in which the helmet ring, waist ring and two shoulder rings make up a system of four interconnected parallel manipulators with tensile links. This configuration allows the dynamic control of both the position and orientation of each of the four rings, enabling modification of critical sizing dimensions such as the inter-scye distance, as well as task-specific orientations such as helmet, scye and waist bearing angles. Half-scale and full-scale experimental models as well as an analytical inverse kinematics model were used to examine the interconnectedness of the plates, the role of external forces generated by pressurized fabric, and the controllability of the system.