The growing interest in plant space biology is motivated by the need to create sustainable life support systems for long-duration human spaceflight. Plants are essential elements of bio-regenerative systems due to their ability to produce food, generate oxygen, recycle carbon dioxide, and help in water purification. One of the significant issues, however, is the stimulation of plant growth under altered gravitational conditions, such like in microgravity environments (~10⁻³ G). While experiments done in space have yielded valuable results, their practical application is frequently hindered by high costs, limited access, and complicated logistical demands (De Pascale et al., 2021). Ground-based simulators like the random positioning machine (RPM) or 3D clinostat are thus becoming increasingly valuable. By rotating samples continuously around two orthogonal axes, RPM creates a temporal averaging of the gravitational vector, thus simulating microgravity conditions (Herranz et al., 2013). We present an economically viable, table-top random positioning machine (RPM) made from easily sourced parts in the market. The device consists of two independent aluminum frames (20×20 mm extrusion) that rotate and are powered by stepper motors, allowing continuous three-dimensional randomization. Rotational speed, orientation, and time are controlled by the Arduino Uno R3 microcontroller, with real-time optimization allowed through feedback sensors. The sample holder, built from aluminum extrusions, is placed in the center of the device and can hold four standard petri dishes, thus allowing simultaneous biological experiments. Built for modularity and accessibility, this RPM provides a practical platform for microgravity research, particularly in resource-constrained research and academic environments. It is a cost-effective entry to space biology and facilitates local capacity building in preparation for future space science missions.

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