The Robotic Refueling Mission (RRM), a joint venture between NASA and the Canadian Space Agency (CSA), develops technologies and techniques for robotic servicing of in-orbit spacecraft. At the end of RRM Stage 1 in 2013, an on-ground team at Goddard Space Flight Center and Johnson Space Center successfully controlled the Canadian Robot arm, Dextre as it refueled the International Space Station (ISS). Dextre is also able to perform several other maintenance tasks.
Now in Stage 2, NASA hopes to establish robotic technologies that can handle tasks such as cryogen replenishment and hardware installation. They also aim to develop adaptors and connection techniques for switching out different functional end pieces on RRM modules.
One recent addition to the ISS is a tiny camera used to investigate tight spaces before repair by other robots. The imaging device, called the Visual Inspection Poseable Invertebrate Robot (VIPIR), is similar to those employed in medical imaging procedures, such as endoscopy. It is still in its testing phase.
The device uses three cameras—one for positional control, another with zooming capabilities for external diagnostics, and a borescope camera for imaging in tight spaces.
The borescope camera is placed on the end of a 34-in. long tube so that it may be fed through spaces smaller than 1-in. in diameter. Because it is only meant to gather near to midrange images, the camera has a relatively low resolution of 0.5 megapixels (224 x 224 pixels). It is claimed as the smallest commercial, off-the-shelf camera, measuring a mere 1.2 mm in diameter. As it travels through an orifice, the camera delivers a 100-degree field of view of its environment. It can also articulate at 90-degree angles for full-range vision.
The camera used for external imaging integrates a motorized 8- to 24-mm optical zoom lens that can capture details as small as 0.02 in., enabling it to find small cracks. Extremely high resolution enables imaging at exact intensifications. Zoom and focus are controlled via two spaceflight-grade motors, each with a diameter of 0.5 in., making them the smallest motors ever used for a camera in space. The third positional-control camera, featuring a fixed 6-mm focal length, enables the control team to move VIPIR around the work site.
The new VIPIR camera will give NASA engineers camera control from the ground to diagnose any problems on the ISS. It is an integral step in using robots to service spacecraft, helping to enhance ergonomics on the ISS by increasing precision in mundane tasks, improve holding times, and replacing astronauts in dangerous work conditions. RMM also brings new potential to robotics and its impact on the workforce here on Earth.