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This paper aims to study the encounter issues of the Tethered-Space Net Robot System (TSNRS) with non-target objects on orbit during the maneuver, including the collision issues with small space debris and the obstacle avoidance from large obstacles.

For the collision of TSNRS with small debris, the available collision model of the tethered net and its limitation is discussed, and the collision detection method is improved. Then the dynamic response of TSNRS is studied and a closed-loop controller is designed. For the obstacle avoidance, the variable enveloping circle of the TSNRS has coupled with the artificial potential field (APF) method. In addition, the APF is improved with a local trajectory correction method to avoid the overbending segment of the trajectory.

The collision model coupled with the improved collision detection method solves the detection failure and speeds up calculation efficiency by 12 times. Collisions of TSNRS with small debris make the local thread stretch and deforms finally making the net a mess. The boundary of the disturbance is obtained by a series of collision tests, and the designed controller not only achieved the tracking control of the TSNRS but also suppressed the disturbance of the net.

This paper fills the gap in the research on the collision of the tethered net with small debris and makes the collision model more general and efficient by improving the collision detection method. And the coupled obstacle avoidance method makes the process of obstacle avoidance safer and smoother.

The work in this paper provides a reference for the on-orbit application of TSNRS in the active space debris removal mission.

In light of the discussions on outer space property management, this conceptual review paper aims to discuss and evaluate if, when and under which conditions certain land management and property right frameworks can apply to allocate and/or restrict property rights in outer space.

This paper applies a pragmatic review approach which seeks to better understand if and how the basic tenets of the land management frameworks could better shape and revise the challenges in outer space regulations.

Despite the fact that regulatory guidelines on outer space rights are existing, the analysis shows that these lack a number of practical tools and measures aiming at intervening if stakeholders do not follow the rules. With the use of land management frameworks, it is possible to derive policy options for making the outer space management more practical and action-oriented, in particular for the removal of space debris. These include amongst others more attention for formulating global public restrictions in outer space, incorporating regulatory guidelines for accessing open space regimes, addressing responsiveness and robustness in adherence and compliance to regulations

Given the conceptual and discursive character of the paper, there are no specific empirical data, yet several recommendations for further research include expanding the boundary work between the land management and regulatory outer space domain.

The insights derived from land management and real estate related property theories could potentially provide new starting points for (re)formulating the regulatory framework for outer space property discourses.

Interpreting the outer space regulations from known and practiced land management perspective helps to bridge the policy–society knowledge and necessity gap on outer space activities.

The specific land management perspective and discursive analysis on outer space debris provide new options for devising and extending regulatory guidelines for assigning responsibilities on outer space debris and debris rights, restrictions and responsibilities.

This article takes into account object identification, enhanced visual feature optimization, cost effectiveness and speed selection in response to terrain conditions. Neither supervised machine learning nor manual engineering are used in this work. Instead, the OTV educates itself without instruction from humans or labeling. Beyond its link to stopping distance and lateral mobility, choosing the right speed is crucial. One of the biggest problems with autonomous operations is accurate perception. Obstacle avoidance is typically the focus of perceptive technology. The vehicle's shock is nonetheless controlled by the terrain's roughness at high speeds. The precision needed to recognize difficult terrain is far higher than the accuracy needed to avoid obstacles.

Robots that can drive unattended in an unfamiliar environment should be used for the Orbital Transfer Vehicle (OTV) for the clearance of space debris. In recent years, OTV research has attracted more attention and revealed several insights for robot systems in various applications. Improvements to advanced assistance systems like lane departure warning and intelligent speed adaptation systems are eagerly sought after by the industry, particularly space enterprises. OTV serves as a research basis for advancements in machine learning, computer vision, sensor data fusion, path planning, decision making and intelligent autonomous behavior from a computer science perspective. In the framework of autonomous OTV, this study offers a few perceptual technologies for autonomous driving in this study.

One of the most important steps in the functioning of autonomous OTVs and aid systems is the recognition of barriers, such as other satellites. Using sensors to perceive its surroundings, an autonomous car decides how to operate on its own. Driver-assistance systems like adaptive cruise control and stop-and-go must be able to distinguish between stationary and moving objects surrounding the OTV.

One of the most important steps in the functioning of autonomous OTVs and aid systems is the recognition of barriers, such as other satellites. Using sensors to perceive its surroundings, an autonomous car decides how to operate on its own. Driver-assistance systems like adaptive cruise control and stop-and-go must be able to distinguish between stationary and moving objects surrounding the OTV.

This paper aims to present a novel method for identification and classification of rotational motion for uncontrolled satellites. These processes are shown in context of close proximity orbital operations. In particular, it includes a manipulator arm mounted on chaser satellite and used to capture target satellites. In such situations, a precise extrapolation of the target’s docking port position is needed to determine the manipulator arm motion. The outcome of this analysis might be used in future debris removal or servicing space missions.

Nonlinear, and in some special cases, chaotic nature of satellite rotational motion was considered. Four parameters were defined: range of motion toward docking port, dominant frequencies, fractal dimension of the motion and its time dependencies.

The qualitative analysis was performed for presented cases of spacecraft rotational motion and for each case the respective parameters were calculated. The analysis shows that it is possible to detect the type of rotational motion.

A novel procedure allowing to estimate the type of satellite rotational motion based on fractal approach was proposed.

The purpose of this paper is to perform a comparative study of two propagation models and a prediction of proximity distances among the space objects based on the two-line element set (TLEs) data, which identifies potentially risky approaches and is used to compute the probability of collision among the spacecrafts.

At first, the proximities are estimated for the mentioned satellites using a precise propagation model and based on a one-month simulation. Then, a study is performed to determine the probability of collision between two satellites using a formulation which takes into account the object sizes, covariance data and the relative distance at the point of closest approach. Simplifying assumptions such as a linear relative motion and normally distributed position uncertainties at the predicted closest approach time are applied in estimation.

For the case of Iridium-Cosmos collision and the prediction of a closest approach using available TLE orbital data and a propagation model which takes into account the effects of the earth’s zonal harmonics and drag atmospheric, the maximum probability of about 2 × 10 −6 was obtained, which can indicate the necessity of enacting avoidance maneuvers regarding the defined a probability threshold by satellite’s owner.

The contribution of this paper is to analyze and simulate the 2009 prominent collision between the Cosmos2251 and Iridium33 satellite by modeling their orbit propagation, predicting their closest approaches and, finally, assessing the risk of the possible collision. Moreover, an enhanced orbit determination can be effective to achieve an accurate assessment of the ongoing collision threat to active spacecrafts from orbital debris and preventing, if necessary, the hazards thereof.

The aim of this paper is to present a discussion on prognosis and mitigation of major landslide zones in an attempt to minimize the impact of such disasters in future. A case study on the sequence of sliding events of Varunavat Parvat, Uttarkashi (India), response of masses and administration and causative factors of sliding events has been presented in detail for prognosis and mitigation of large slide zones.

The prognosis and mitigation strategy discussed is based on the monitoring of mass wasting zones through field investigations and satellite image analysis (of pre‐ and post‐landslide period images) and experiential learning and interaction with village elders in landslide hazard‐prone Himalayan terrain.

The paper finds that Himalayan habitations such as Uttarkashi (which is situated in an area of fragile rocks, complex tectonics, seismic activity and cloud burst‐prone unstable hill slopes with colluvium and old slide zones) should have minimum anthropogenic activity in the form of slope cutting for road or building construction.

The paper reflects the author's individual understanding of causative factors and indications of landslides in Varunavat Parvat area in Uttarkashi township of Uttarakhand (India).

The paper calls for amalgamation of experience‐based local knowledge of villagers of landslide‐prone areas and modern scientific and technical know‐how and above all the coordinated efforts of community and authorities for prognosis and mitigation of large‐scale landslides in the inhabited areas. It has been further emphasized that sensitization and awareness programs and strict implementation of land‐use regulations are vital components of effective mitigation strategy.

In 1987, Campbell Soup Company introduced the Souper Combo, a line of frozen soup and sandwiches. Melvin Druin, vice‐president for packaging, called it “the perfect combination of old‐fashioned good taste and today's convenience. No mess. No fuss. Easy to use. All you have to do is clean your spoon. Everything else just throw away.” Unfortunately, the multi‐layered plastic‐coated packaging does not just disappear when thrown away. Plastics packaging, particularly from convenience products, has become a waste disposal nightmare. Garbage, an environmental magazine, gave the Souper Combo an “in the dumpster” award, saying, “It's precisely the kind of product that's created the municipal landfill monster.”

The tendency of urban environments to produce anxiety is well documented in a range of theoretical and historical literature, but there is little current work that considers how public spaces might be designed to alleviate anxiety among their users. This paper presents a series of case studies taken from a lighting design project on the Kentish Town Road in north London to show how urban design can create a more psychologically inclusive public realm — one that offers greater psychological comfort — by enhancing the engagement between users of urban spaces and their environment. The argument is presented in the context of broader issues of social inclusion and other current movements in urban design.