MoonRanger’s Power Switching Board is a printed circuit board that distributes and switches power to components such as the computers, motor controllers and sun sensor. In the event of a device or board failure, the switching can attempt to restore functionality by power cycling. If unrecoverable, the affected device can be powered down by the … Continued
All commands and data to and from MoonRanger are conveyed via Wi-Fi when it is within radio range of its lander. For redundancy, it matters that both MoonRanger’s computers have independent means of Wi-Fi to the lander. The Wi-Fi chip on the autonomy computer (TX2i) facilitates most of the direct-to-lander comm. The simpler, more hardened … 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. The 3D-printed MoonRanger look-alike that will be used as a form around which the robot’s multi-layer insulation ‘blanket’ will be ‘sewn’. Despite freezing shadows on the Moon, rover batteries and electronics have to remain at a moderate operating temperature. This is like a human maintaining internal body temperature at 98.6 degrees Fahrenheit in … Continued
Figure 1: Inverted chassis prepared for hammer testing A roving hammer test is the simplest way to determine natural frequencies of a structure. The structure is tapped with a small hammer, and the resulting frequencies are sensed through instrumentation. It is a bit like striking a bell and sensing the frequency of its vibration by … Continued
MoonRanger’s motor control board incorporates five of the individual motor control modules. These are coordinated by the space-grade microcontroller (the gray square component in the upper left) that commands the speed, direction and motion duration of each. Four controllers drive the wheels in this way. The fifth raises or lowers the solar array.https://www.youtube.com/watch?v=HrEBQpYZa-QThis video illustrates … Continued
MoonRanger’s radiation viability is achieved via component selection, shielding, short mission duration, testing, error correction and monitoring. Some components, including power management, primary and watchdog computers, accelerometer, and intelligent battery are selected for radiation tolerance, prior rad testing, or space heritage. Shielding is utilised for critical components that lack space heritage and boards developed by … Continued
MoonRanger’s motor controller is located inside of the power electronics unit (PEU). This custom circuit board is designed to control each brushless DC actuator through its full range of speed and torque and is based around the space-rated TI UC1625-SP BLDC gate driver chip. This chip has a terrestrial equivalent, the TI UC2625, which allows … Continued