Servo - January 2007

Figure 7. Fake Astronaut on RMS.

was to be able to move a specially modified RMS arm about the SS. Brian Fuller and Tom Young of Spar supplied me with RMS technical data and our group developed a Mobile Transporter to carry the space station version of the RMS over all the faces of the space station structure. We had to keep the weight to a mini-

Figure 8. The Author and His Mobile Transporter Module.

All Electronics Corp. ............................. 23, 72

AP Circuits ..................................................... 79

COMBOTS ..................................................... 33

Command Productions ................................. 7

CrustCrawler ................................................... 3

Electronics123 .............................................. 72

Futurlec ......................................................... 23

Hitec .............................................................. 79

Hobby Engineering ...................................... 14

Jameco Robot Store ................................ 2, 23

90 SERVO 01.2007

mum so we decided not to use an attached rail system all over the SS.

The design that we came up with used a series of doorknob-sized pins all about the SS structural surface. The mobile transporter used two sets of forks to grasp the knobs and pull itself along the surface. Figure 8 is a model of the MT that I’m holding and shows the fork assemblies and the two slotted rails through which the knobs traveled as it pulled itself along like a person climbing a ladder. The MT could turn at a node, rotate 90° to a new surface by means of swivel joints in the middle of the two rails, and carry the RMS while it was attached to a large payload. The white box contains a series of nickel-hydrogen batteries, the control electronics, and the fork actuators.

Figure 9. SSRMS with Manipulator.

Advertiser Index

Lorax Works .................................................. 73

Lynxmotion, Inc. ........................................... 19

Maxbotix ....................................................... 23

Maximum Robotics ................................ 23, 25

Net Media ..................................................... 91

NU-BOTICS .................................................... 72

Parallax, Inc. ................................... Back Cover

Plantraco ................................................. 23, 72

Pololu Robotics & Electronics ..................... 38

The Canadarm 2 Space Station RMS

The Space Station is quite a bit further along since my days on the program. The new 58 foot, 7 degree-of-freedom Canadarm 2 Space Station RMS was installed on the SS in April of 2001 (see Figure 9). The new system is self-relocatable (it can relocate itself anywhere on the SS) and is the key component of the $896 million Mobile Servicing System (MSS).

The MSS is composed of two other components besides the SSRMS — The Special Purpose Dexterous Manipulator (SPDM) and the Mobile Remote Servicer Base System (MBS). The SPDM is a small, advanced detachable two-armed robot that can be placed on the end of the RMS arm to install and remove small payloads and similar delicate operations. The (MBS) is a movable platform for the Canadarm2 and the SPDM that slides along rails on the Space Station’s main structure to transport Canadarm2 to various points on the Station.

A lot of progress has been made on these space systems since I worked on the program in the late ‘80s and early ‘90s. The International Space Station is a reality and can be seen by the naked eye as it crosses the sky. I truly enjoyed my small part in developing robotic systems for space. As I always say, use your favorite search engine to keep abreast of the Space Station’s robotic developments.