Pneumatic Sampling in Extreme Terrain with the Axel Rover

Some of the most interesting regions of study in our solar system lie inside craters, canyons, and cryovolcanoes, but current state-of-the-art rovers are incapable of accessing and traversing these regions. Axel is a minimalistic rover designed for extreme terrains, and two Axels with a central mother system form a four-wheeled rover to efficiently traverse flat ground. Upon approaching the edge of a crater, Axel detaches from the mother system and travels down the cliff guided by the unwinding tether. However, scientific study of extraplanetary terrains requires instrumentation inside the Axel rover. We aim to develop a simple and reliable sample acquisition and caching system that could retrieve multiple samples from various sites before returning them to the mother system where more sophisticated instruments could perform further analysis. For simplicity and robustness, we propose a pneumatic sampling system which uses compressed air, guided with a nozzle, to blow soil into a sample canister. Numerous types of nozzles were designed, built, and tested. Different designs for nozzle deployment, sample caching, and pressure containment were considered. Finally, a prototype of the entire sampling system was built and evaluated for performance and feasibility

Tools and Algorithms for Sampling in Extreme Terrains

Extreme-terrain robots such as JPL’s Axel rover are enabling access to new and exciting science opportunities. The goal of this mini-program was to develop a compact sampling instrument for Axel. Over the summer of 2012, a small group of students designed, built, and tested prototype sampling devices. Nikola Georgiev created a versatile four-degree-of-freedom scoop, which can acquire up to 4 different samples in clean self-sealing containers. Hima Hassenruck-Gudipati studied percussive scooping, and prototyped a percussive scoop that takes advantage Axel’s independent body rotation to acquire samples. Kristen Holtz and Yifei Huang collaborated on a pneumatic sampling system, which uses a puff of air to propel loose grains into flexible tubing, and separates the grains into an interchangeable sample container. Each of these sampling systems has been demonstrated, and each proved useful for different conditions. In turn, the students gained valuable design experience and the opportunity to work alongside a number of experts in various fields

Percussive Scoop Sampling in Extreme Terrain

Axel is a minimalistic cliff climbing rover that can explore extreme terrains from the moon, Mars, and beyond. To increase the technology readiness and scientific usability of Axel, a sampling system needs to be designed and build for sampling different rock and soils. To decrease the amount of force required to sample clumpy and possibly icy science targets, a percussive scoop could be used. A percussive scoop uses repeated impact force to dig into samples and a rotary actuation to collect the samples. Percussive scooping can reduce the amount of downward force required by about two to four times depending on the cohesion of the soil and the depth of the sampling. The goal for this project is to build a working prototype of a percussive scoop for Axel

Tools and Algorithms for Sampling in Extreme Terrains

Extreme-terrain robots such as JPL’s Axel rover are enabling access to new and exciting science opportunities. The goal of this mini-program was to develop a compact sampling instrument for Axel. Over the summer of 2012, a small group of students designed, built, and tested prototype sampling devices. Nikola Georgiev created a versatile four-degree-of-freedom scoop, which can acquire up to 4 different samples in clean self-sealing containers. Hima Hassenruck-Gudipati studied percussive scooping, and prototyped a percussive scoop that takes advantage Axel’s independent body rotation to acquire samples. Kristen Holtz and Yifei Huang collaborated on a pneumatic sampling system, which uses a puff of air to propel loose grains into flexible tubing, and separates the grains into an interchangeable sample container. Each of these sampling systems has been demonstrated, and each proved useful for different conditions. In turn, the students gained valuable design experience and the opportunity to work alongside a number of experts in various fields

Science and technology requirements to explore caves in our Solar System

Research on planetary caves requires cross-planetary-body investigations spanning multiple disciplines, including geology, climatology, astrobiology, robotics, human exploration and operations. The community determined that a roadmap was needed to establish a common framework for planetary cave research. This white paper is our initial conception

Martian Lava Tube Exploration Using Jumping Legged Robots: A Concept Study

In recent years, robotic exploration has become increasingly important in planetary exploration. One area of particular interest for exploration is Martian lava tubes, which have several distinct features of interest. First, it is theorized that they contain more easily accessible resources such as water ice, needed for in-situ utilization on Mars. Second, lava tubes of significant size can provide radiation and impact shelter for possible future human missions to Mars. Third, lava tubes may offer a protected and preserved view into Mars' geological and possible biological past. However, exploration of these lava tubes poses significant challenges due to their sheer size, geometric complexity, uneven terrain, steep slopes, collapsed sections, significant obstacles, and unstable surfaces. Such challenges may hinder traditional wheeled rover exploration. To overcome these challenges, legged robots and particularly jumping systems have been proposed as potential solutions. Jumping legged robots utilize legs to both walk and jump. This allows them to traverse uneven terrain and steep slopes more easily compared to wheeled or tracked systems. In the context of Martian lava tube exploration, jumping legged robots would be particularly useful due to their ability to jump over big boulders, gaps, and obstacles, as well as to descend and climb steep slopes. This would allow them to explore and map such caves, and possibly collect samples from areas that may otherwise be inaccessible. This paper presents the specifications, design, capabilities, and possible mission profiles for state-of-the-art legged robots tailored to space exploration. Additionally, it presents the design, capabilities, and possible mission profiles of a new jumping legged robot for Martian lava tube exploration that is being developed at the Norwegian University of Science and Technology.Comment: 74rd International Astronautical Congress (IAC

Biomechanical study of the Spider Crab as inspiration for the development of a biomimetic robot

A problem faced by oil companies is the maintenance of the location register of pipelines that cross the surf zone, the regular survey of their location, and also their inspection. A survey of the state of art did not allow identifying operating systems capable of executing such tasks. Commercial technologies available on the market also do not address this problem and/or do not satisfy the presented requirements. A possible solution is to use robotic systems which have the ability to walk on the shore and in the surf zone, subject to existing currents and ripples, and being able to withstand these ambient conditions. In this sense, the authors propose the development of a spider crab biologically inspired robot to achieve those tasks. Based on these ideas, this work presents a biomechanical study of the spider crab, its modeling and simulation using the SimMechanics toolbox of Matlab/Simulink, which is the first phase of this more vast project. Results show a robot model that is moving in an “animal like” manner, the locomotion, the algorithm presented in this paper allows the crab to walk sideways, in the desired direction.N/

Rigid Wheel and Grouser Designs for Off-Road Mobility

A wheel includes a circular wheel main body and at least one grouser. The at least one grouser is provided along an outer circumference of the wheel main body and has a contact surface capable of drawing a first tangent line. The first tangent line is inclined opposite to a rotational direction of the wheel main body from the center line of the wheel main body

Advanced BIT* (ABIT*): Sampling-Based Planning with Advanced Graph-Search Techniques

Path planning is an active area of research essential for many applications in robotics. Popular techniques include graph-based searches and sampling-based planners. These approaches are powerful but have limitations. This paper continues work to combine their strengths and mitigate their limitations using a unified planning paradigm. It does this by viewing the path planning problem as the two subproblems of search and approximation and using advanced graph-search techniques on a sampling-based approximation. This perspective leads to Advanced BIT*. ABIT* combines truncated anytime graph-based searches, such as ATD*, with anytime almost-surely asymptotically optimal sampling-based planners, such as RRT*. This allows it to quickly find initial solutions and then converge towards the optimum in an anytime manner. ABIT* outperforms existing single-query, sampling-based planners on the tested problems in $\mathbb{R}^{4}$ and $\mathbb{R}^{8}$, and was demonstrated on real-world problems with NASA/JPL-Caltech.Comment: IEEE International Conference on Robotics and Automation (ICRA) 2020, 6 + 1 pages, 3 figures, video available at https://youtu.be/VFdihv8Lq2