Scholarlink

<p>With expanding spaceflight mission plans to the Moon, Mars, and beyond, investigating biological phenomena in reduced-gravity environments is a critical need. Ground-based spaceflight-analog platforms, such as the two-frame Random Positioning Machine (RPM), represent an alternative to operationally challenging spaceflight-based experiments. We developed a kinematic model to define the acceleration and gravitational level experienced by a sample at the center of an RPM. In comparing this to the RPM’s performance with accelerometers and motion capture sensors, we validated the RPM and defined optimized performance parameters for time-averaged microgravity and reduced-gravity simulation (rotation rate: outer frame &gt; 30&#xa0;deg/s, inner frame &gt; 20&#xa0;deg/s slower; sample size: &lt;10–15&#xa0;cm from the center depending on rotation rate; experimental duration: &gt;25&#xa0;min). We also present the validated designs for an RPM capable of simulating microgravity, lunar gravity, Martian gravity, and hypergravity simultaneously. Finally, we identify “pole bias” as a critical limitation for two-frame RPMs: when the outer frame is aligned vertically, which occurs twice during each rotation, the gravity vector is aligned with a sample and generates two poles. At higher rotation rates, this significantly reduces the fidelity of an RPM’s reduced-gravity simulation, and we thus introduce the design and validation for a novel three-frame RPM that can mitigate pole bias. We validated the RPM platform, optimized experimental design guidelines, and identified novel RPM designs for microgravity and reduced-gravity investigations.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Guidelines for use of the random positioning machine as a reduced-gravity analog

  • 期刊论文

  • 出版模式：

    开放获取

  • 发表日期：

    2026年2月20日

查看全文
  • Anna Wadhwa,
  • Lasse Bruun,
  • Johan C. G. Petersen,
  • Lonnie G. Petersen

摘要

With expanding spaceflight mission plans to the Moon, Mars, and beyond, investigating biological phenomena in reduced-gravity environments is a critical need. Ground-based spaceflight-analog platforms, such as the two-frame Random Positioning Machine (RPM), represent an alternative to operationally challenging spaceflight-based experiments. We developed a kinematic model to define the acceleration and gravitational level experienced by a sample at the center of an RPM. In comparing this to the RPM’s performance with accelerometers and motion capture sensors, we validated the RPM and defined optimized performance parameters for time-averaged microgravity and reduced-gravity simulation (rotation rate: outer frame > 30 deg/s, inner frame > 20 deg/s slower; sample size: <10–15 cm from the center depending on rotation rate; experimental duration: >25 min). We also present the validated designs for an RPM capable of simulating microgravity, lunar gravity, Martian gravity, and hypergravity simultaneously. Finally, we identify “pole bias” as a critical limitation for two-frame RPMs: when the outer frame is aligned vertically, which occurs twice during each rotation, the gravity vector is aligned with a sample and generates two poles. At higher rotation rates, this significantly reduces the fidelity of an RPM’s reduced-gravity simulation, and we thus introduce the design and validation for a novel three-frame RPM that can mitigate pole bias. We validated the RPM platform, optimized experimental design guidelines, and identified novel RPM designs for microgravity and reduced-gravity investigations.