Real-Time 3D Lunar Excavation Simulation using the Digital Spaces Open-Source Platform FINAL PROJECT PRESENTATION Bruce Damer, CEO, Digitalspace Corp Dave Rasmussen, Merryn Nelson, Peter Newman, DM3D Studios Brad Blair, Engineering Consultant May 31, 2007

Precursor Simulations Digitalspace (DS) generated prior driveable simulations of mobile lunar exploration and ISRU systems Relevant NASA SBIR-funded work included –CSM Bucket Wheel Excavator –NASA Robotic Lunar Exploration Rover –Physics models for these sims were limited to vehicle mobility and arm articulation only A “Clean Room” simulation of a grabber arm and blocks was also created by DS for experimental purposes

CSM Bucket Wheel Excavator Simulation

RLEP 2 Mobility trade study Use of Plow as Trenching Tool in Sampling Area

RLEP 2 Mobility trade study Deployment of Drill Assembly-Lower Pose

RLEP 2 Mobility trade study Cut Away of Drill Action

RLEP 2 Mobility trade study Engage Plow for Braking

DS “Clean Room” sim of grabber arm with blocks

Lunar Excavation Simulation A real-time, driveable, physics-based simulation was then proposed to NASA-SOMD as a tool to examine lunar excavation operations The physics model would be expanded to include soil mechanics An output file would be generated containing engineering data Partners for the project included National Securities Technology LLC and Los Alamos National Laboratories

Sketch of “Jell-O Block” concept

Sim #1: Backhoe in “Clean- Room” Environment Backhoe style excavator was created and rigged using physics model Jell-O blocks introduced into ‘clean room’ environment Volumetric friction (viscosity) used to provide ‘drag forces’ while bucket is inside block

Sim #2: Excavators and Balovnev Soil Mechanics Model No mobility in Sim #2 Concentrated on implementing proof-of-concept for Balovnev soil mechanics model for excavator blade resistance Three excavators were modeled: Bucket Wheel, Front-end loader and Clamshell Lack of constraints caused tipping of mobility platforms (validating force increase with depth of penetration)

Sim #3: Lunar Excavators at Polar Lunar Base Site Three lunar excavation systems were then rigged, constrained to dig into the uppermost regolith layer, and placed in a simulated lunar polar base site Waypoints were added to automatically guide each excavator through a mining sequence Output files were generated for torques and forces for each excavator Sophisticated user interaction with physics model (including Balovnev soil resistance) was enabled through input windows

Sim #3 Cut-Away Views of Excavation Box An ‘Excavation Test Box’ was rigged with the Balovnev soil mechanics model in order to collect force and torque data The following views show the excavators penetrating the surface plane into the test box Three excavators automatically repeat the mining cycle by loading regolith then driving to the dump zone and unloading using waypoints Notice suspended rock hazards

Sim #4: Bucket Ladder Excavator A fourth simulation was built for the fourth excavator – a bucket ladder The system was placed in an ‘improved’ version of the lunar polar base site Physics modeling and user input windows were derived from simulation #3 Minor improvements were made to ‘debug’ the DSS software platform and improve sim performance