This paper presents a concept for a low-cost, in-space robotic assembly mission that can be achieved from an ESPA (EELV Secondary Payload Adapter) ring. It also presents results of an in-lab validation experiment conducted to evaluate the feasibility of the concept. The central idea is to use autonomous robotics to incrementally assemble a segmented antenna from its discrete segments that are efficiently packed for launch. The antenna is assembled on a small spacecraft mounted on one port of the ESPA ring while the antenna segments are compactly stowed in another port of the ESPA. The robot and its avionics are integral to the spacecraft. Alternately, the ESPA could also be the host spacecraft. In the validation experiment, a commercially available C-band segmented, 2m class antenna is assembled using autonomous robotics in a manner consistent with the concept of operations of the mission concept. Vision-guided, force-controlled dexterous robotics is used in a scripted autonomy manner to successfully demonstrate the antenna assembly without any human intervention. The paper discusses the mission concept, the rationale behind using robotic assembly, details of the in-laboratory experiment, and salient observations.

Climbing robots can investigate scientifically valuable sites that conventional rovers cannot access due to steep terrain features. Robots equipped with microspine grippers are particularly well-suited to ascending rocky cliff faces, but most existing designs are either large and slow or limited to relatively flat surfaces such as walls. We present a novel free-climbing robot to bridge this gap through innovations in gripper design and force control. Fully passive grippers and wrist joints allow secure grasping while reducing mass and complexity. Forces are distributed among the robot’s grippers using an optimization-based control strategy to minimize the risk of unexpected detachment. The robot prototype has demonstrated vertical climbing on both flat cinder block walls and uneven rock surfaces in full Earth gravity.

Future surface missions will require accessing new extreme environments which reach cryogenic temperatures. The Cold Operable Lunar Deployable Arm (COLDArm) system and component technologies can enable future missions in these extreme environments, including lunar night and Ocean Worlds. Here we report on the design, fabrication, and initial testing of the COLDArm system. The project is funded through the Lunar Surface Innovation Initiative (LSII) and managed by the NASA Space Technology Mission Directorate (STMD) Game Changing Development (GCD) program. The COLDArm system is developed with industrial partner, Motiv Space Systems, Inc (Pasadena, CA). The robotic arm leverages a design similar to the Mars Phoenix and Mars InSight robotic arms. The arm is four degrees of freedom (DOF), approximately two meters in length, and has a tip force greater than 40 newtons in the primary workspace. The significant innovation of the robotic arm is the ability to work in cryogenic environments without heaters. Eliminating heaters provides the benefits of reducing system energy needs and removing heat from mechanisms located near volatile sample collection locations. The robotic joints include a planetary gearmotor and strainwave gear which utilize bulk metallic glass (BMG) gears to eliminate the need for heaters. Both the BMG planetary gearmotor and BMG strainwave gear have been successfully demonstrated at cryogenic temperatures. Additionally, the Dual-Axis Controller for Extreme Environments (DACEE) motor controller also eliminates the reliance on a warm electronics box (WEB). The DACEE motor controllers have also been successfully demonstrated at cryogenic temperatures. A Robotic Avionics and Sensor Kit (RASK) is located on the baseplate in a WEB. The RASK leverages the avionics design used on the Ingenuity Mars Helicopter which has been successfully demonstrated on Mars. COLDArm specific functionality has been added, including a 4-k resolution stereo camera pair and a force torque sensor (FTS) interface. Flight software (FSW) was also developed which leverages the Ingenuity FSW utilizing the F prime framework. An end effector was designed in collaboration with Kennedy Space Center (KSC) and Glen Research Center (GRC) to collect geotechnical properties from the lunar regolith. End effector features include a scoop and geotechnical tool geometries to enable measurement of regolith properties such as bearing capacity, angle of repose, shear strength, and pressure-sinkage parameters. The geotechnical scoop tool was designed for Titanium additive manufacturing in collaboration with Marshall Space Flight Center (MSFC) following NASA-STD- 6030. A cryogenic capable FTS is located at the end effector to collect six-axis load information during the ground interactions. This FTS leverages the design from Mars 2020 and has been demonstrated at cryogenic temperatures. After fabrication and integration of the system, check-outs in the lab environment confirmed basic functionality of the system. Advanced functional testing was completed in the Jet Propulsion Laboratory (JPL) Lunar Advanced Robotics (LunAR) Lab, including ground interaction demonstrations with GRC-3b lunar regolith simulant. These ground interactions demonstrations included large surface pressure sinkage, angle of repose, and shear tests.

Microspine grippers allow robots to ascend steep rocky slopes and cliff faces, enabling scientific exploration of exposed strata on Earth and other solar system bodies. Historically, the Shape Deposition Manufacturing (SDM) process has been used to fabricate multi-material suspensions for load-sharing among multiple microspines. We instead apply the Hybrid Deposition Manufacturing (HDM) process to microspine fabrication, and we further propose a novel 3D-printed microspine suspension design that can be manufactured via Fused Deposition Manufacturing (FDM) alone, using a single flexible material with an embedded fishhook. We use a model of microspine stiffness that allows designers to compensate for order-of-magnitude changes in material tensile modulus by adjusting geometric parameters of the design. The stiffness model and the FDM microspine design are validated through tensile testing, and mechanical properties of the HDM and FDM designs are compared against a standard SDM microspine design. We demonstrate that the FDM process can produce microspines with equivalent normal and axial stiffness and superior maximum load and fatigue response to SDM microspines, and discuss additional advantages of the FDM process for rapid prototyping and broader accessibility.

Volcanoes are one of the great forces of the natural world. The gases they release can reveal information about the world below us, from the structure of the planet, to the risk of an imminent eruption. Sampling these gases however is often difficult and extremely dangerous - high temperatures, hazardous gases, steep terrain and remoteness all make collecting samples a challenging endeavour. Unoccupied Aerial Vehicles (UAVs) can help reduce the risks and difficulties of measuring and sampling these gases, enabling studies of volcanic systems that were otherwise inaccessible. This paper presents the first known effort to design, develop and field test a UAV-borne Gas Capture System (UGCS) for volcanic fumarole sampling. This work includes the development of a sampling probe deployment mechanism, sample canister selection, payload-to-UAV interfacing, and a light-weight visual/thermal camera package. Operationally, the intricacies of placing a sample probe into a small fumarole opening are examined, as are the hazards of flying a UAV with a suspended load.

In this paper, we discuss a concept for a Radio Frequency (RF) Ka band communications payload that is robotically assembled and serviced in space using a servicing vehicle such as the Robotic Servicing of Geosynchronous Satellites (RSGS) vehicle being developed by the Defense Advance Research Projects Agency (DARPA). Our work focuses on how to modularize a representative Ka band communications payload into discrete modules that are hosted on a persistent platform. In our concept, each module consists of a primary aperture and the associated RF and electronics required to serve a particular coverage area or type. These modules are notionally packaged in a form factor capable of launching as a secondary payload via an EELV Secondary Payload Adapter (ESPA) ring or a Payload Orbital Delivery System (PODS) module. The overall payload consists of an earth coverage module, regional coverage modules, high gain regional coverage modules, and a host interface unit (HIU). We discuss the notional capabilities and requirements of each module. We present two different architecture concepts corresponding to two different persistent platform concepts. In one concept, the persistent platform is made up of small, independent spacecraft that are connected together with structural members with communication channels. The payload modules are hosted on the individual spacecraft. In the second approach, the platform consists of a large central spacecraft with a structural truss that has power, communication and thermal loops. The payload modules are hosted on the truss through standard interfaces. We present aspects of the mission concept on how the payload may be modularized, launched (as secondary launch elements), acquired by the RSGS vehicle in space and assembled on to the persistent platform. We discuss the robotics aspects of assembly and servicing of the payload modules. A key aspect of this concept is the serviceability of the payload. Central to the modular and discrete payload design is an intent to refurbish the payload incrementally as technology evolves or the components fail. Existing geosynchronous communication satellites are designed and built as monolithic spacecraft which makes any servicing beyond refueling fairly complicated. This makes it hard to take advantage of the post launch evolution in technology, particularly in the electronics elements. Our concept is aimed at modularizing the payload such that the modules, particularly the electronics elements, can be easily serviced using the RSGS vehicle. Our concept attempts to take advantage of the long service life of high reliability system components in the core satellite bus while allowing rapid expansion and upgrading of the communications payload through the addition and replacement of individual payload modules.

We present the design and experimental results for the JPL-Nautilus Gripper, a 16-finger highly underactuated microspine gripper for use in the deep ocean. The gripper can grasp objects from 10 to 30 cm in size and anchor to flat and curved rocky surfaces (i.e., cliff faces and seamounts). Laboratory results demonstrated an anchoring capability of greater than 450 N on rough rocks in both shear and normal loading directions. Deployment on the Hercules ROV (remotely operated vehicle) aboard the E/V Nautilus on three deep-ocean dives verified performance at depths up to to 2,100 m with approximately 100 N loads applied through the ROV's thrusters, including moment loads. The gripper also serves as a development unit for future robotic tools that will include a coring drill in the center of the gripper, as previously demonstrated in non-ocean environments with microspine grippers. Such a tool will facilitate the collection of geologic samples from the deep ocean using more agile and cost-effective systems.

In this paper, we present the design, characterization, and functional demonstration of a perching system that enables a flying vehicle to land on rough sloped or vertical surfaces. Steep slopes are of particular scientific interest since they are often associated with geologically interesting features including sites of active modification (e.g. landslides/avalanches, slope streaks), exposed bedrock and/or ice, and as-yet unmodified young features (e.g. walls of fresh craters or polar pits that are actively expanding). However the steep nature of these sites makes access with traditional field robots difficult: ground vehicles are unable to traverse the steep terrain and aerial vehicles are limited by their flight time and an ability to operate near terrain. We propose to address these limitation by enabling the UAV to reliably perch on steep terrain to perform in situ measurements and collect samples. Perching also enables a solar powered UAV to traverse large terrain features such as the Valles Marineris that could not be covered in a single flight by repeatedly perching and recharging its batteries. The proposed perching system that is being developed consists of a microspine gripper, a compliant gripper to vehicle interface, and a flying vehicle equipped with an autonomy sensor suite. The system also includes perception and control algorithms that identify perching targets and execute the required perching maneuver. To date, the majority of the effort has focused on developing and characterizing the microspine gripper. The initial prototype weighs 100 g, is capable of securely grasping a range of natural surfaces, and successful grasps support loads of over 10 N. Refinement of the gripper, integrating and testing it on a UAV, measuring aerodynamic disturbances from wall effects, and developing the required perception and control algorithms is ongoing. This paper describes the overall architecture of our proposed system, the design of the gripper, and its performance during initial testing.

The ability to perform robotic manipulation and assembly actions in space bears great potential for aerospace applications and is a critical milestone in NASA’s future technology plans [1], [2]. On-orbit assembly maneuvers, in particular, would facilitate a wide range of important tasks such as rendezvous and docking, satellite servicing, debris removal, or even in-space manufacturing of larger structures. However, the required technology differs substantially from today’s autonomous planetary manipulation capabilities exhibited by Mars rovers. Dynamic perception and action generation is needed to deal with changing environmental conditions. We propose an integrated system for conducting in-space assembly in a purely autonomous fashion or via limited human supervision. The system combines mechanical and algorithmic solutions to the challenges encountered in onorbit assembly. In particular, we leverage an arm-augmented cubesat to allow for low-cost and high-fidelity operations. The specially-designed Remora arm features six degrees of freedom and weighs ≈ 0.75 kg [3]. As a result of the limited weight and the cubesat form-factor, the proposed system can be rapidly built and deployed requiring only a fraction of the costs of a more traditional space robotics framework. The second important component to our system is a Rendezvous and Proximity Operations (RPO) software stack that includes a combination of modern computer vision and robot-control algorithms. In particular, the RPO package is responsible for (1) estimating the state (6D pose in CubeSat reference frame) of manipulated objects, and (2) generating control assembly maneuvers. State estimation is performed via a computationally efficient model-based tracking algorithm, which matches given CAD models of truss components with images taken from cameras positioned on the cubesat. The matching process is realized by solving an iterative re-weighted least squares (IRLS) problem minimizing the residual between projected 3D CAD model edges and image edges [4]. The process also makes use of recent insights from sample-efficient local optimization techniques. In particular, an adaptive learning rate optimization algorithm is used to achieve fast convergence towards accurate 6D pose estimates of manipulated objects. The RPO stack also includes functionality for learning task-specific motion primitives closed-

In this paper we present the overall architecture of a “Science Station”, a robotically assembled and serviced persistent platform that can host multiple payloads for Earth observations. Recent decadal survey findings motivate the need to have spatial and temporal concurrency in measurements from multiple instruments. We have architected the science station to simultaneously host up to twelve Earth Venture class instruments at a time. These instruments can be replaced by newer instruments periodically to take advantage of evolving science needs and technology capabilities. The Science Station can also concurrently host science, commercial, defense and other national interest payloads. The Science Station may provide a cost-effective paradigm by mitigating some of the risks and costs associated with multiple free-flyers that may otherwise be needed for the various instruments. It leverages emergent and existent technologies in robotic assembly and servicing, lower cost commercial launch vehicles, secondary launch vehicles, and rendezvous and proximity operations. In this paper, we report the findings of a survey we conducted on the desired performance of the Science Station from various instrument hosting perspectives. We report the various trade studies that we conducted to developed a feasible architecture that meets the goals of the Science Station while also meeting the constraints of a space system. We also report the various considerations in the configuration, thermal system, pointing system, overall concept of operations, and the robotic system of the Science Station architecture. The paper then describes a testbed activity we are undertaking to evaluate the supervised autonomy robotics needed for the Science Station as well as to conduct a risk-reduction demonstration of the end-to-end robotics behaviors.

Here, we present the design, fabrication, and evaluation of a prismatic-revolute-revolute joint hand called the model B that we developed for grasping from ungrounded vehicles. This hand relies on a prismatic proximal joint followed by revolute distal joints in each finger and is actuated by a single motor-and a tendon-based underactuated transmission. We evaluate this design's grasping capabilities both when fully constrained by a robotic arm and when minimally constrained and evaluate its performance in terms of general grasping capabilities and suitability for aerial grasping applications. The evaluation shows that the model B can securely grasp a wide range of objects using a wrap grasp due to the prismatic-revolute-revolute joint finger kinematics. We also show that the prismatic proximal joints and between finger coupling allows the hand to grasp objects under large positional uncertainty without exerting large reaction forces on the object or host vehicle.

This paper presents the feasibility study of the REMORA CubeSat mission concept with an integrated miniature robotic payload to prevent large debris collisions. While orbital debris poses a threat to spacecraft, a collision between the largest space debris objects is of significant concern. The DARPA Catcher's Mitt study compiled a list of the highest priority large debris objects. By annually removing 5-10 of these high priority objects, it may be possible to stabilize the medium sized debris population. Instead of deorbiting objects, REMORA would use COTS CubeSat components and secondary payload launches as a cost-effective solution for mitigating large debris collisions. The REMORA CubeSat could rendezvous with a piece of debris and use the robotic manipulator to anchor itself to the target object. Once anchored, the CubeSat could track the debris and, if needed, alter the debris object's trajectory to prevent a collision. Aspects discussed include the mission and robotic payload baseline designs. Many of the highest priority objects identified in the DARPA Catcher's Mitt study are located in the 71°-75° inclination range and in sun-synchronous orbit. An initial mission design concept targets sun-synchronous objects due to the large number of launch opportunities to this orbit. The mission was simulated with a combination of MATLAB, GMAT, and STK. A CubeSat robotic payload was designed to provide a decreased chance of collision between the CubeSat and debris object during attachment, augment the ACS during approach, and provide the ability to orient the thrust vector through the center of mass while pushing. This robotic payload includes a computing element, cameras, miniature robotic arm, and end-effector. An initial miniature arm prototype was designed and built to demonstrate feasibility and inform future designs. An end-effector trade study was performed to explore different end-effectors that could be used to for attaching to the common graspable features on large debris objects. Grasping methods, including mechanical prehension, gecko grippers, electrostatic grippers, and magnetic grippers, were investigated.

Adding grasping and manipulation capabilities to unconstrained vehicles such as UAVs, AUVs, and small space craft so that they can deliver cargo, grasp and retrieve objects, perch on features in the environment, and even manipulating their environment is an ongoing area of research. However, these efforts have relied heavily on structuring the interaction task and have predominantly utilized existing gripper designs that were not specialized for the platform or task. In this paper, we present a parametric model of a novel underactuated hand design that is composed of prismatic-revolute-revolute joint fingers. This kinematic configuration attempts to minimize disturbance forces to the body of the vehicle while achieving stable grasps on a wide range of objects under significant positional uncertainty. In particular, this paper investigates the impact of various design parameters, including the relative link lengths and force allocation across the three joints, on grasping performance and suggests optimal design parameters for a prototype hand.

In this letter, we present the design of an underactuated three-fingered robotic hand and evaluate its performance. The hand utilizes radially symmetric, prismatically actuated fingers controlled by a single actuator. Each finger consists of a single joint finger connected to the prismatic joint via a passive rotational joint perpendicular to the palm. The rotational joints allow the fingers to passively switch between spherical and cylindrical grasps while the finger joint allows the fingers to wrap about the grasped object. We compare the performance of this design to that of a concentric gripper with cylindrical fingers and two other underactuated hand designs using the YCB grasping benchmark. This evaluation shows that the three finger prismatic hand performs well especially when equipped with the single joint fingers in comparison to other designs.

The grasping capability of birds' feet is a hallmark of their evolution, but the mechanics of avian foot function are not well understood. Two evolutionary trends that contribute to the mechanical complexity of the avian foot are the variation in the relative lengths of the phalanges and the subdivision and variation of the digital flexor musculature observed among taxa. We modelled the grasping behaviour of a simplified bird foot in response to the downward and upward forces imparted by carrying and perching tasks, respectively. Specifically, we compared the performance of various foot geometries performing these tasks when actuated by distally inserted flexors only, versus by both distally inserted and proximally inserted flexors. Our analysis demonstrates that most species possess relative phalanx lengths that are conducive to grasps actuated only by a single distally inserted tendon per digit. Furthermore, proximally inserted flexors are often required during perching, but the distally inserted flexors are sufficient when grasping and carrying objects. These results are reflected in differences in the relative development of proximally and distally inserted digital flexor musculature among ‘perching’ and ‘grasping’ taxa. Thus, our results shed light on the relative roles of variation in phalanx length and digit flexor muscle distribution in an integrative, mechanical context.

of 23847 CRP's were identified; indications for surgery were: malignant tumor 50.4%, benign tumor 14.2%, diverticulitis 23.5%, IBD 10.2%, and other 1.7%.The operations performed were: segmental resection, 84.5%; APR/proctectomy 8.7%; and total colectomy 6.8%.Stomas were constructed in 21.8% and laparoscopic methods used in 56.3% of cases.The mean LOS was 6.4±5.4 days and the mortality rate 0.8 %.Unplanned readmission occurred in 10.2% of patients and the reoperation rate was 4.7%.The overall morbidity rate was 24.3%; 40.1% of the complications occurred after discharge.Readmission was required for 49.7% of patients with post-discharge complications.The individual complication data is presented in the following order: 1) the overall rate of the complication in question, 2) the percentage of patients with that complication diagnosed post discharge, and 3) the percentage of patients with that complication who were readmitted.The most frequent complications after discharge were: superficial SSI, 6.8%, 59.7%, 26.6%; sepsis, 3.4%, 36.4%,92.4%; Organ Space SSI, 4.0%, 49.3%, 88.9%; and UTI, 2.8%, 42.9%, 40.4%.Rarer complications with a high readmission rate were: pneumonia, 1.4%, 18.5%, 71.4%; DVT 1.2%, 47.2%, 73.1%; wound disruption, 1.1%, 51.3%, 59.6%; progressive Renal Insufficiency, 0.7%, 49.7%, 86.4%; Pulmonary Embolism, 0.6%, 46.3%, 88.2%; and CVA/Stroke, 0.2%, 33.3%, 92.3%.Conclusion: Forty percent of complications occurred after discharge and half the affected patients required readmission.The most common late complications were superficial SSI, organ space infection, sepsis, and UTI.The readmission rate for individual complications varied from 26-90 %.It is not clear to what extent discharge delays recognition of the complication and the start of treatment.After discharge, CRP's should be followed closely in order to diagnose and treat late complications early.When assessing costs for inpatient procedures it is critical to include costs associated with late complications including readmission and treatments.

In the past two decades, much advancement has been made in the area of organ procurement and preservation for the transplant of kidneys, livers, and lungs. However, small intestine preservation remains unchanged. We propose a new preservation system for intestinal grafts that has the potential to increase the viability of the organ during transport. When experimented with porcine intestine, our device resulted in superior tissue quality than tissue in standard of care.

This paper examines aspects of robot hand performance specific to grasping and perching from an aerial vehicle and shows how various hand design parameters affect performance. Specifically, we consider hand performance when subject to external forces imparted to the hand from carrying a payload or from perching on a fixed item and explore the impact of design and grasp parameters including tendon routing/pulley ratio, object size, and palm size on the performance of both fully and underactuated designs. Our results show that underactuated designs utilizing a single actuator per finger are sufficient in all cases we studied, but that fully actuated designs can perform better for perching applications. Additionally, we find that increasing the palm width improves performance both when perching and grasping, and that a small distal/proximal pulley ratio is beneficial for payload carriage but counterproductive for perching.