Browsing by Author "Halbach, Eric"
Now showing 1 - 3 of 3
- Results Per Page
- Sort Options
Item Multi-Robot Hillside Excavation Strategies for Mars Settlement Construction(47th International Conference on Environmental Systems, 2017-07-16) Halbach, EricMulti-robot earthmoving strategies were studied for the simulated excavation of a large hillside section. This could be the first construction phase of a permanent settlement on Mars, which would consist of masonry structures built in the dug-out area and buried under a regolith layer for protection. The robotic fleet consists of 8 compact skid-steered wheel loaders and 8 or more dump trucks. The basic strategy is to assign each loader its own workspace along the slope face, separated from neighbouring workspaces to avoid possible conflicts, and for two loaders to share the same dump truck for load transfer while extra trucks wait. The workspaces are arranged along a row which advances into the hillside after all material in the row is excavated, in an attempt to excavate the slope evenly. The strategies developed generate commands which nominally allow the robots to operate autonomously until job completion. Various parameters can be modified in the simulator, such as the workspace dimensions, dump truck location, and slope height. Several simulations were conducted in order to test the effect of these parameters on the excavation rate and amount of driving required by the machines. It was found that while the workspace dimensions could be adjusted to increase the excavation rate, larger advantages could be gained by positioning the machines favourably so as to decrease the driving needed for load transfer.Item Solar Array Configurations for the Moon Village(2020 International Conference on Environmental Systems, 2020-07-31) Halbach, Eric; Inocente, Daniel; Haney, Max; Katz, Neil; Petrov, Georgi I.The Moon Village master plan is an architectural concept for a sustainable, international human outpost on the rim of Shackleton Crater near the lunar South Pole. This site receives nearly continuous sunlight throughout the lunar year, providing a clear benefit for human psychological needs and technically, as it can greatly contribute to solar power generation. In general, a solar panel would need to be oriented vertically, facing the horizon, while rotating 360° to track the Sun, which varies in elevation angle by only some +/-1.5° at the proposed location. To support a growing settlement, an array of several panels could be installed within a ground area. This faces the problem, however, that panels currently exposed to the Sun may occlude those behind, lowering the total exposure and making some configurations ineffective if many panels remain highly occluded. This problem was studied by comparing the simulated exposure of various array configurations during a lunar daily cycle. First ground spacing was considered for arrays of 2 to 5 panels. Mean total exposure was found to increase by up to 66% if the array's circular ground area diameter was increased to three times the minimum, while the actual array configuration had a small effect. For predefined square ground areas, several versions of six array types were tested. For smaller numbers of wider panels, several configurations offered similar mean exposures. Filling the available area with more, narrower panels could result in a gradual increase in mean exposure, or a decrease due to more gaps between panels. The Arrow array achieved ~96% of the available mean exposure using the least total panel area, while the X-array provided similar mean and full minimum exposure using the least panel area. Hexagonal configurations provided ~98% of the available mean, and the full minimum, using more panel area.Item Solar Arrays with Variable Panel Elevations for the Moon Village(50th International Conference on Environmental Systems, 7/12/2021) Halbach, Eric; Inocente, Daniel; Katz, Neil; Petrov, Georgi I.The Moon Village master plan by Skidmore, Owings & Merrill and the European Space Agency is a concept for a permanent human settlement near the lunar South Pole, on the rim of Shackleton Crater. The project location has been determined to receive nearly continuous sunlight throughout the lunar year, offering the potential for nearly continuous solar power generation. One challenge, however, is that the Sun remains near the horizon during the lunar daily cycle. For an array of several solar panels deployed in a ground area, panels currently facing the Sun would cast long shadows, possibly occluding other panels behind. A previous study by the authors identified favorable spatial configurations of vertically-oriented solar panels which increased the average exposed total panel area while minimizing the number of panels or total panel area. One simplifying assumption was the use of panels at the same elevation in each array. Using panels with different elevations, however, offers the possibility of increasing solar panel exposure for a given ground deployment area. The previous study is therefore extended in this paper by studying arrays with panels that can have different fixed or actuated elevations, in order to find favorable configurations to increase average solar exposure during a simulated lunar day. Two automatic panel control strategies are proposed for circular array configurations: Automatic Elevation Control makes is possible to achieve maximum panel exposure using two elevation levels, while Automatic Angle Adjustment (AAA) addresses the problem of partial panel shading by rotating some panels away from the solar incidence angle in order to avoid shadowing from other panels. In one example, AAA provides up to a 45% increase in the exposed area of unshaded panels compared with each panel facing the Sun at a perpendicular angle.