International audienceA core flow test autoclave has been designed in order to reproduce an injection well at a scale of 1/20. This autoclave allows the CO2 injection into a steel tube cemented to a core sample of red sandstone from the Triassic formations of Lorraine (France). Temperature and pressure gradients can be recorded between the injection point and the confining water phase. Such gradients imply solubility gradients of CO2 and mineral species into the water phase as permeability changes with time. Some chemical reactions can be observed from collected sample at the end of the experiment. Precipitation and dissolution are suspected both into the cement and rock phases. No fracturing is observed. Cement-rock interface is not opened

Abstract-Hyper-redundant manipulators can be fragile, expensive, and limited in their flexibility due to the distributed and bulky actuators that are typically used to achieve the precision and degrees of freedom (DOFs) required. Here, a manipulator is proposed that is robust, high-force, low-cost, and highly articulated without employing traditional actuators mounted at the manipulator joints. Rather, local tunable stiffness is coupled with off-board spooler motors and tension cables to achieve complex manipulator configurations. Tunable stiffness is achieved by reversible jamming of granular media, which-by applying a vacuum to enclosed grainscauses the grains to transition between solid-like states and liquid-like ones. Experimental studies were conducted to identify grains with high strength-to-weight performance. A prototype of the manipulator is presented with performance analysis, with emphasis on speed, strength, and articulation. This novel design for a manipulator-and use of jamming for robotic applications in general-could greatly benefit applications such as human-safe robotics and systems in which robots need to exhibit high flexibility to conform to their environments. [6], and to create a variable stiffness endoscopic tube [7]. The combination of these projects highlights the primary benefits of utilizing jamming for robotics:it allows robots to be more human-safe, inexpensive, and robust compared to most technologies that have traditionally been used for such applications.The goal of this paper is to further the use and understanding of jamming for engineering applications. Specifically, we present the design and analysis of a robotic manipulator composed of 1) serial modules that can transition between rigid and flexible states via jamming and 2) tension cables running along the length of the manipulator and whose lengths are controlled by spooler motors. We previously demonstrated this robotic architecture of coupling locally tunable stiffness with global actuation as a thrust toward soft robotics [8] [9]. One of the main benefits of this type of system is that by eliminating the need for distributed-and often rigid and bulky-actuators throughout the robot, the system can be more robust and flexible, enabling it to conform to its environment better. In addition, the cost of the robot can be drastically reduced.In this paper we also begin to explore how grain properties affect the performance of jammed systems. Specifically, we seek to maximize the strength-to-weight ratio of jammed systems. This is an important figure of merit for manipulators, where the robot must be able to support its own weight in addition to any payloads.Because granular systems inherently lack mechanical structure in their unjammed states, their flexibility and high DOFs can be beneficial for hyper-redundant robotic systems such as a manipulator. Most approaches in hyper-redundant robotics have involved employing distributed and rigid pneumatic or electromagnetic actuators. Much of the effort in this area has been in dev...

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Abstract-Future planetary exploration missions will require wheeled mobile robots ("rovers") to traverse very rough terrain with limited human supervision. Wheel-terrain interaction plays a critical role in rough-terrain mobility. In this paper, an online estimation method that identifies key terrain parameters using on-board robot sensors is presented. These parameters can be used for traversability prediction or in a traction control algorithm to improve robot mobility and to plan safe action plans for autonomous systems. Terrain parameters are also valuable indicators of planetary surface soil composition. The algorithm relies on a simplified form of classical terramechanics equations and uses a linear-least squares method to compute terrain parameters in real time. Simulation and experimental results show that the terrain estimation algorithm can accurately and efficiently identify key terrain parameters for various soil types.Index Terms-Mobile robots, planetary rovers, rough terrain, wheel-terrain interaction.

[1] This paper summarizes Spirit Rover operations in the Columbia Hills, Gusev crater, from sol 1410 (start of the third winter campaign) to sol 2169 (when extrication attempts from Troy stopped to winterize the vehicle) and provides an overview of key scientific results. The third winter campaign took advantage of parking on the northern slope of Home Plate to tilt the vehicle to track the sun and thus survive the winter season. With the onset of the spring season, Spirit began circumnavigating Home Plate on the way to volcanic constructs located to the south. Silica-rich nodular rocks were discovered in the valley to the north of Home Plate. The inoperative right front wheel drive actuator made climbing soil-covered slopes problematical and led to high slip conditions and extensive excavation of subsurface soils. This situation led to embedding of Spirit on the side of a shallow, 8 m wide crater in Troy, located in the valley to the west of Home Plate. Examination of the materials exposed during embedding showed that Spirit broke through a thin sulfate-rich soil crust and became embedded in an underlying mix of sulfate and basaltic sands. The nature of the crust is consistent with dissolution and precipitation in the presence of soil water within a few centimeters of the surface. The observation that sulfate-rich deposits in Troy and elsewhere in the Columbia Hills are just beneath the surface implies that these processes have operated on a continuing basis on Mars as landforms have been shaped by erosion and deposition.