The Next Step SPACE ROBOTICS INITIATIVE Skyworker-TIM2 12/8/99-1 Skyworker Assembly, Inspection, and Maintenance of SSP Facilities Field Robotics Center

The Next StepSPACE ROBOTICS INITIATIVE

Skyworker-TIM2 12/8/99-1

SkyworkerSkyworkerAssembly, Inspection, and Maintenance of SSP FacilitiesAssembly, Inspection, and Maintenance of SSP Facilities

SkyworkerSkyworkerAssembly, Inspection, and Maintenance of SSP FacilitiesAssembly, Inspection, and Maintenance of SSP Facilities

Field Robotics Center

December 8, 1999

William “Red” WhittakerPeter StaritzChris Urmson



Space Solar Power Assembly, Space Solar Power Assembly, Inspection, and Maintenance (AIM)Inspection, and Maintenance (AIM)

Space Solar Power Assembly, Space Solar Power Assembly, Inspection, and Maintenance (AIM)Inspection, and Maintenance (AIM)

• Extensive structures – Kilometers in dimension– Millions of parts

• SSP environment– Wide temperature range, sometimes

exceeding 500K– Solar Proton Events– Galactic Cosmic Radiation– Microwave Radiation– Kilovolt buses

• Long duration operations– 1 year construction– 30 years operation



Motivation for a Robotic WorkforceMotivation for a Robotic WorkforceMotivation for a Robotic WorkforceMotivation for a Robotic Workforce

• High, inaccessible orbit

• Overwhelming EVA agenda– Millions of parts– 10’s of Millions of

Manipulations

• Long term operations

• Harsh environment

• Robots are expendable and repairable

• Lower support costs



Assembly, Inspection, and Assembly, Inspection, and Maintenance TasksMaintenance Tasks

Assembly, Inspection, and Assembly, Inspection, and Maintenance TasksMaintenance Tasks

• 3D agile traversal of a truss structure

• Pick up and place payloads at arbitrary locations and orientations

• Carry payloads while walking, turning, and transitioning planes

• Conduct calibration and inspection tasks

• Connect power and communications cables

• Cooperatively carry bulky, massive payloads

• Perform tasks that require multiple robot collaboration

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Possible AvenuesPossible AvenuesPossible AvenuesPossible Avenues• Free Flying Systems

– Require expenditure of mass to move– Result in tons of spare fuel– Risky docking operations

• Fixed Manipulators (e.g. shuttle & station)– Anchored to a hard point on the structure– Limited reach– Longer reach results in larger dynamic/reaction forces

• Attached Mobile Manipulators (AMM)– No mass expenditure– “Unlimited” reach– Ability to “walk lightly”– Temporarily attach for working reaction forces

• AMM is the archetype for SSP AIM



Skyworker ScopeSkyworker ScopeSkyworker ScopeSkyworker Scope

• Robot Prototype and Software Simulation– Demonstrate the viability of

using robots for orbital construction

– Prove the validity of using structure walkers for orbital AIM

– Demonstrate SSP AIM relevant tasks using robotics

– Simulate prospective SSP AIM robots and tasks



SkyworkerSkyworkerSkyworkerSkyworker• Self Contained

• Continuous gait allows payload to move at constant velocity– Requires less energy– Exerts less stress on the

structure (walks lightly)

• Counterbalanced to emulate micro g

• Onboard processor and distributed control network

• Mass: ~35 kg

• Dimensions: 3 m x .5 m x .1 m

• 11 DOF



Skyworker SimulationSkyworker SimulationSkyworker SimulationSkyworker Simulation

• 3D visualization of SSP AIM activity

• Allows study of operations, and scale effects

• Kinematic models demonstrate extended operations– Coordinated operations– Long term, large scale

tasks



Results to DateResults to DateResults to DateResults to Date

• Skyworker developed

• Component testing complete

• Simulation package operational

• Concept to operation in 99 days



DemonstrationDemonstrationDemonstrationDemonstration

• Prototype– Pick up and carry a model transmitting element the length of the

truss, turn while carrying, couple the element to the structure– Perform a mock calibration– Demonstrate “walking lightly”

• Simulation– Perform prototype robot tasks– Perform plane transition– Assemble a large scale construction utilizing multiple robots

• Emphasis placed on system level activity– Current grippers and sensors are placeholders for future

development



Development TeamDevelopment TeamDevelopment TeamDevelopment Team

• Skyworker has been developed by a team of staff and students at CMU

• William “Red” Whittaker

• Chris Gaiser

• Oren Laskin

• Dewitt Latimer

• Jason Messinger

• Jonathan Samuel

• Sarjoun Scaff

• Peter Staritz

• Chris Urmson

• Tim Warneck

• Will Wong



Skyworker DOFSkyworker DOFSkyworker DOFSkyworker DOF

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Documents

The Next Step SPACE ROBOTICS INITIATIVE Skyworker-TIM2 12/8/99-1 Skyworker Assembly, Inspection, and Maintenance of SSP Facilities Field Robotics Center