There is a great need within all space programs to evaluate electrical and mechanical hardware during operation under various thermal conditions. Analysis is a critical tool during the early design of hardware but verification via physical testing is crucial. Electronic boards and motors become non-operational at low temperatures so the demonstration of adequate heating systems … Continued

A rover mission has two landings. The first is when the lander reaches the surface, and the second is when the rover’s wheels touch the ground and roll away. These are preceded by the violent shaking of the launch that requires attachment to the lander to be stiff, strong and certain. Once on the Moon, … Continued

One of the great distinctions of space robotics versus terrestrial robotics is that every component, device, sensor and electronic element has to function in vacuum. Once in vacuum, Earth’s convection due to air circulation no longer exists, so regulation of heating and cooling in a space system relies on the far weaker mechanism of radiation, … Continued

MoonRanger’s carbon fiber composite chassis shell was a triumph of design, process and master craft. Although metal design and machining is much more straightforward, only a composite solution was sufficiently lightweight. A campaign of design, facility development, mold-making, process development, layup, curing and machining created this elegant structural element. The 18” x 17” x 4” … Continued

During the mission, MoonRanger’s bolted connections are subject to tensile, shear, thermal loads, and the effects of vibration and creep. The desired initial tensioning of the bolt is computed based on these factors. Determining and implementing the correct torque for each bolt on a space robot is essential engineering, process and discipline. Connectors for a … Continued

Invariant relative positioning and focus of cameras is vital for the success of MoonRanger’s stereo perception. The slightest change during mission can create inaccurate depth models and therefore non-functional obstacle avoidance. Positioning variables include the spacing between the cameras, their vergence (zero vergence in the case of MoonRanger), and their relative dip angle (“twist”). Camera … Continued

Autonomy Computer Gallery The aluminum shell protects the autonomy computer from radiation and electromagnetic interference (EMI), and conducts heat from the computer through the rover’s deck to black space. The lip around the top edge creates an ‘EMI labyrinth’ to protect the computer from external noise. A large, heavy, layered design was originally conceived to … Continued

Fabrication methods (for example, of the composite chassis shell), as-demonstrated mobility, vibration test correlations to predictions, and other purposes require a high fidelity physical prototype whose tangible validity surpasses the design and analysis of early development. For these purposes Terramule was developed, served effectively, and continues to serve the MoonRanger program. A high precision mold … Continued

Figure 1: Testbed for evaluating MoonRanger’s perception. Material, color and lighting are lunar-like. The line of rectangular blocks are at known locations for verifying that the terrain geometry created by the robot matches the geometry of the scene. LUNAR POLAR LIGHT It is challenging to illuminate a perception testbed with lighting that emulates sunlight that … Continued