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Venus is a planet that we would very much like to further explore and understand. However, the surface of Venus is very hostile environment with a surface temperature averaging 452 degrees centigrade at an atmospheric pressure of 93 bar, with the atmosphere composed mainly of carbon dioxide with clouds of sulfuric acid. Missions to the surface of Venus have succeeded, but mission lifetime is extremely short, on the order of minutes to hours, until materials melt and electronic components fail due to the extreme conditions. A small rover that would be capable of exploring the surface would be scientifically valuable, but requires unconventional thinking to be able to survive the environment. We present a study of means by which to design a small planetary rover that uses a bio-inspired flexible tensegrity structure and operates mechanically to utilize the conditions of the Venusian surface in its operation. Tensegrity robots make use of geometrically-inspired and bio-inspired structures that allow multiple degree of freedom movement. These structures are sparse, composed of linked tension and compression members in a similar manner to a truss, and are very lightweight compared to traditional mobile robots and retainin the ability to flexibly adapt to terrain and fold for transport. The use of a tensegrity structure also has benefits in terms of simplicity of structure, in the sense that structural elements are simple and repeatable, held in place only by the tension of materials. This allows tensegrity rovers to utilize smart materials and structural properties in operation, without the use of complex joints and bearings to allow full-body movements. The use of flexible structures allows the rover to transform and re-configure itself to a limited extent in the field in response to environmental factors. In this paper, a concept and feasibility study of a small tensegrity rover that utilizes mechanical operation will be examined for Venus exploration, with consideration of previous missions and their lessons. The use of the rover for scientific exploration will also be justified. The results of this study will also benefit terrestrial applications that require robotic operation in the presence of extremes of temperature and pressure. The work will be used for the development of space technology for very harsh and hot planetary exploration.

Autonomous Robotic vehicles represent a key and fast-moving technology area in space exploration and exploitation. We aim to to make future operations on other planets more affordable, reliable, and responsive by developing better and more useful mobile robots that can be deployed on other planets, and expediting this process by applying similar technologies to robotic applications on Earth. These robots must be responsive, energy efficient, lightweight for transport, and mechanically robust. To accomplish these goals, we have developed the Aria micro-rover platform based on micro-rover concepts for low-cost Mars surface and subsurface exploration and inspired by the recent resurgence of interest in planetary exploration. The Aria is designed using a novel methodology for probabilistic autonomy programming that makes use of Bayesian networks for highly reliable sensor fusion, planning, and behaviour control. Autonomy and AI are accomplished by inference-based reasoning into stored probabilistic data, and includes probabiliistic learning and self-programming. A fully distributed electronic component architecture with fault tolerance increases modularity and adaptability. Reliability is maximized and cost of deployment is minimized by modularly re-using common hardware and components. Also, the mechanical structure uses a lightweight and flexible actuated space frame to increase resiliency and allow full-body movements. The use of flexible structures allows the rover to transform and re-configure itself to a limited extent in the field. The physical design is driven by the need for light weight, simplicity and reconfigurability, with a minimalist mechanical structure and a flexible software design model to facilitate additions and multiple use cases. To lower cost of construction and transport, mass is minimized through the use of thin structural members and wire members in tension to create resilience without adding additional material. The Aria platform is unique in its aim to be constructed using as much automation as possible during manufacture. The chassis makes use of a jointed frame that can be assembled using additive manufacturing methods. The electronics are common modules that are attached and connected during the manufacturing process using a common bus architecture and later programmed for component-specific duties. The mission responsiveness of the platform is very high due to the ability to re-use and re-configure modules as needed for mission changes. This also opens the possibility for rovers to be mass-produced and deployed autonomously, or even assembled on another planet by using local materials to save transport of mass. In addition to the ability to be deployed as a planetary rover for scientific or resource management use, the Aria rover is targeted at terrestrial applications by using similar but non space qualified electronics to lower cost and increase availability. The primary applications targeted are 1) agricultural field monitoring and intervention, 2) environmental sensing and research uses, and 3) surveillance and disaster response. The Aria rover platform represents a new paradigm in deploying mobile robots to perform remote missions on Earth and other planets. Prototypes are currently being tested, and the technologies refined to produce more reliable, responsive, and flexible configurations for the applications of the future.

A novel adaptive unscented Kalman filter (AUKF) based estimation algorithm is proposed for a 3U Cubsat. This small satellite employs a three axis magnetometer and three MEMS gyroscopes as well as three magnetic torque rods and one reaction wheel on the pitch axis. Unlike the existing UKF, in this paper, an n+1 sigma set is used to estimate the nanosatellite attitude instead of 2n + 1 sigma points as in a conventional UKF. Numerical Simulation results validate the performance of the proposed adaptive Kalman filter. There is no need for linearization of the nonlinear dynamics of the system. The estimated result tracks satellite attitude during the damping and stable control stages. Euler angles, gyro bias, and angular velocity of the satellite are estimated using this proposed AUKF with good convergence time and estimation accuracy.