Microrovers: Current and Past Examples and

Conclusions

Microrover Space Horizons WorkshopBrown University

Feb. 16, 2012

Bruce Betts, Ph.D.The Planetary Society

• What is a microrover? – No precise definition currently. – One example: 1 to roughly 10 kg;

MUSES-CN to Sojourner

• Lots of examples in design and Earth use, only Sojourner in flight

• We’ll look at microrovers:– Coolness– Catalog– Examples– Uses– Conclusions

Microrovers

Why are microrovers cool?

• Low cost, mass, volume imply:– Several can be piggybacked on missions– Increase capability, decrease risk for low cost– Power advantage: higher power to mass ratio

for smaller rovers– Can use in riskier ways if desired,– Mitigate risk by flying multiple– Easy to deploy

• Microrovers lead to new paradigms

Background: Cornell/TPS Microrovers Project

• The Planetary Society– Bruce Betts– Louis Friedman– Doug Stetson– Interns

• Cornell University– Jim Bell (later ASU)– Mason Peck– Joseph Shoer– Yervant Terzian– S/C Engineering class

• Stellar Exploration– Tomas Svitek and associates

• Independent– Tom Jones

• TM at JPL– Brian Wilcox

•Much of what is presented here came out of a Cornell/Planetary Society project (NASA Steckler Grant) to study Microrovers for use with astronauts.

•Though focus with astronauts, many products/conclusions remain useful for robotic only

Microrover Catalog• Created online microrover catalog

• What has been done for space and Earth on microrovers.

• Want to help new groups:– Not reinvent “the wheel”– Stimulate design thoughts

• One stop info on over 100 Terrestrial and Planetary Rovers (up to 100 kg for comparison)

• Tells us what we missed

Online Microrover Catalog

http://planetary.org/microrovers

Examples of current/recent microrovers

• Only “microrover” flown: Sojourner (11.5 kg) on Mars Pathfinder.

• MUSES-CN (1 kg) was also developed for flight by JPL

Example prototypes for space

JPL Sample Return Rover

Carleton U./CSA Kapvik (30 kg)Neptec/CSA Juno prototype

ESA Nanokhod (1.5 kg)

Earth uses examples (note design variety)

Inuktun VGTV (commercial inspection) 6 kg Hirose/Fukushima Titan IX

(defense/commercial) prototype mine removal

Recon robotics Recon scout 0.5 kg, defense

iRobot SUGV 11 kg defense

How can we use microrovers?

– Reconnaissance:• scout possible traverses (e.g., for large

rover, or for astronauts) • even more efficient if use multiple• several microrovers quickly explore area

compared to one large rover– Science: wide range possible from

imaging to contact science depending on payload.

– High risk exploration, • e.g., steep slopes, lava tubes

How can we use microrovers (2)

• Increasing Astronaut/Big Rover Safety– Enable focusing EVAs/Big

rover traverses on optimized tasks

– Facilities Inspection– Communications relays for

astronauts working “over the next hill”

How can we use microrovers (3)

• Increase Public Excitement/Involvement– Will be “fun” and engaging for the

public– Enable additional perspectives

imaging spacecraft, facilities, and astronauts (family portrait)

• Increase Student Involvement– Like CubeSat analogy, standardized

microrover conducive to university/student run projects

– Can have limited student/public teleoperation

Design Studies

• We did some basic design studies• One semester long Cornell engineering

design class on this topic (~50 students)• Provided input to follow-on professional

study (Stellar/TPS/Cornell), which distilled and added to student studies, and developed general and specific conclusions

Sample 3-Student Team Projects

Some General Conclusions

• Microrovers 1 - 11 kg offer unique benefits and risks, significantly different from larger rovers

• Paradigm shift: not a single rover that does it all, allows new concept of operations

• A group of microrovers may accomplish more, with fewer issues of reliability and lower cost than a single, large rover

• Low mass and easily stowed, microrovers adaptable to flexible, everyday use compared to larger

Specific Conclusions• Power/insulation solutions exist to allow a

microrover to survive the lunar night; • Mechanically matching an astronaut's speed

should not be a driving requirement for the rover's mobility subsystem. Instead: – Virtual proximity through network, and– Recon, science, inspection prior to or in place of

astronaut EVA

• Microrovers can provide GPS-like position knowledge

Specific Conclusions (2)

• Microrovers could have same core design, but portions including payload could reconfigured, ideally in a plug-and-play fashion.

• Working collaboratively as a network allows tasks to be shared among many nodes, including communications relay.

• Teleoperation, autonomous, or both. Ideally, both – at least limited autonomy.

Web and Email

• http://planetary.org/microrovers (Microrover catalog and additional

info/papers from TPS/Cornell study)

• Contact: bruce.betts@planetary.orgLet me know what is missing from catalog.