Winston
Lorenzo von Matterhorn
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March 25, 2019
Venus Landsailing Rover
https://www.nasa.gov/directorates/spacetech/niac/2012_Phase_I_venus_landsailing_rover/
In work to develop sensors to work inside of jet engines, NASA Glenn has developed electronics that will continue to function even at the Venus temperature of 450°C. These electronic components represent a breakthrough in technological capability for high temperatures. We have also tested solar cells up to Venus surface temperatures; although the power density produced is low (because of the high cloud levels and thick atmosphere), we can produce electrical power on the surface. So the fundamental elements of a rover for Venus are not beyond the bounds of physics: we could survive the furnace of Venus-- if we can come up with an innovative concept for a rover that can move on extremely low power levels.
From the linked PDF:
https://www.nasa.gov/sites/default/...geoffrey_landis_venus_landsailer_zephyr_0.pdf
The Zephyr Venus Landsailer is a science mission concept for exploring the surface of Venus with a mobility and science capability roughly comparable to the Mars Exploration Rovers (MER) mission, but using the winds of the thick atmosphere of Venus for propulsion. It would explore the plains of Venus in the year 2025, near the Venera 10 landing site, where wind velocities in the range of 80 to 120 cm/s were measured by earlier Soviet landing missions. These winds are harnessed by a large wing/sail which would also carry the solar cells to generate power. At around 250 kg, Zephyr would carry an 8 m tall airfoil sail (12 m^2 area), 25 kg of science equipment (mineralogy, grinder, and weather instruments) and return 2 Gb of science over a 30 day mission.
Due to the extreme temperatures (450 °C) and pressures (90 bar) on Venus, Zephyr would have only basic control systems (based on high temperature silicon carbide (SiC) electronics) and actuators. Control would come from an orbiter which is in turn controlled from Earth. Due to the time delay from the Earth a robust control system would need to exist on the orbiter to keep Zephyr on course. Data return and control would be made using a 250 MHz link with the orbiter with a maximum data rate of 2 kbps. At the minimal wind speed required for mobility of 35 cm/s, the vehicle move at a slow but steady 4 cm/s by positioning the airfoil and use of one wheel that is steered for pointing control.
Navigation commands from the orbiter will be based upon navigation cameras, simple accelerometers and stability sensors; Zephyr’s stability is robust, using a wide wheel base along with controls to ‘feather’ or ‘luff’ the airfoil and apply brakes to stop the vehicle in the case of unexpected conditions. This would be the science gathering configuration. The vehicle itself would need to be made from titanium (Ti) as the
structural material, with a corrosion-barrier overcoating due to extreme temperatures on the surface.
■ The wind speed is key—need at least 35 cm/s wind or larger sail area and/or lightened craft to enable use of less wind
■ Larger wheels reduce rolling friction
■ Zephyr designed to have mobility over 10 cm debris
■ Pressure vessels and cooling electronics would be too heavy to allow sailing
■ Components (especially actuators and electronics) must be capable of operating in Venus environment (~450 °C, 90 bar, hostile atmosphere)SiC (or equivalent high-temperature semiconductor) electronics key to operations
■ controlling of vehicle in real-time from a ‘Smart’ Orbiter
■ The large sail area and low power requirements allow for solar power
■ Solar cells (0.33% effective efficiency at Venus conditions) and sodium-sulfur (NaS) batteries
exist for Venus high temps
Venus Landsailing Rover
https://www.nasa.gov/directorates/spacetech/niac/2012_Phase_I_venus_landsailing_rover/
In work to develop sensors to work inside of jet engines, NASA Glenn has developed electronics that will continue to function even at the Venus temperature of 450°C. These electronic components represent a breakthrough in technological capability for high temperatures. We have also tested solar cells up to Venus surface temperatures; although the power density produced is low (because of the high cloud levels and thick atmosphere), we can produce electrical power on the surface. So the fundamental elements of a rover for Venus are not beyond the bounds of physics: we could survive the furnace of Venus-- if we can come up with an innovative concept for a rover that can move on extremely low power levels.
From the linked PDF:
https://www.nasa.gov/sites/default/...geoffrey_landis_venus_landsailer_zephyr_0.pdf
The Zephyr Venus Landsailer is a science mission concept for exploring the surface of Venus with a mobility and science capability roughly comparable to the Mars Exploration Rovers (MER) mission, but using the winds of the thick atmosphere of Venus for propulsion. It would explore the plains of Venus in the year 2025, near the Venera 10 landing site, where wind velocities in the range of 80 to 120 cm/s were measured by earlier Soviet landing missions. These winds are harnessed by a large wing/sail which would also carry the solar cells to generate power. At around 250 kg, Zephyr would carry an 8 m tall airfoil sail (12 m^2 area), 25 kg of science equipment (mineralogy, grinder, and weather instruments) and return 2 Gb of science over a 30 day mission.
Due to the extreme temperatures (450 °C) and pressures (90 bar) on Venus, Zephyr would have only basic control systems (based on high temperature silicon carbide (SiC) electronics) and actuators. Control would come from an orbiter which is in turn controlled from Earth. Due to the time delay from the Earth a robust control system would need to exist on the orbiter to keep Zephyr on course. Data return and control would be made using a 250 MHz link with the orbiter with a maximum data rate of 2 kbps. At the minimal wind speed required for mobility of 35 cm/s, the vehicle move at a slow but steady 4 cm/s by positioning the airfoil and use of one wheel that is steered for pointing control.
Navigation commands from the orbiter will be based upon navigation cameras, simple accelerometers and stability sensors; Zephyr’s stability is robust, using a wide wheel base along with controls to ‘feather’ or ‘luff’ the airfoil and apply brakes to stop the vehicle in the case of unexpected conditions. This would be the science gathering configuration. The vehicle itself would need to be made from titanium (Ti) as the
structural material, with a corrosion-barrier overcoating due to extreme temperatures on the surface.
■ The wind speed is key—need at least 35 cm/s wind or larger sail area and/or lightened craft to enable use of less wind
■ Larger wheels reduce rolling friction
■ Zephyr designed to have mobility over 10 cm debris
■ Pressure vessels and cooling electronics would be too heavy to allow sailing
■ Components (especially actuators and electronics) must be capable of operating in Venus environment (~450 °C, 90 bar, hostile atmosphere)SiC (or equivalent high-temperature semiconductor) electronics key to operations
■ controlling of vehicle in real-time from a ‘Smart’ Orbiter
■ The large sail area and low power requirements allow for solar power
■ Solar cells (0.33% effective efficiency at Venus conditions) and sodium-sulfur (NaS) batteries
exist for Venus high temps
