Robotic Lunar Exploration Program

1.Overview 1.1 Project Objective 1.2 Lunar Surface Reference Missions: Proposed Tasks

1.1 Project Objective  Build a robotic prototype, controlled autonomously if possible, that will address operational issues.  Build a robotic prototype, controlled autonomously if possible, that will address operational issues.  It should be able to manipulate and collect soil samples, and dig trenches.  It should be able to manipulate and collect soil samples, and dig trenches.  It should have easy adaptability for unpredicted instruments, repair work, part replacement, and all around versatility.  It should have easy adaptability for unpredicted instruments, repair work, part replacement, and all around versatility.  It will benefit space exploration by helping build a lunar habitat for astronauts to live and train for other missions, a refueling station for ships, as well as future unforeseen projects.

1.2 LSRM  Scientific exploration.  Determining suitability of Moon  Developing technology and conducting tests relevant to long-term human stays  Developing tests relevant to further explorations i.e. Mars and beyond  Testing technologies that might lead to economic benefits  Understanding crew health, safety and performance, and effectiveness for long stays on the moon

2. Research 2.1 Non-prehensile Manipulation 2.2 Excavation Methods 2.3 Microcontrollers 2.4 Other Electrical Research

2.1 Non-prehensile manipulation  Grasp  Kinematic grasp FixturingFixturing  Quasistatic grasp Using sliding and stationary forcesUsing sliding and stationary forces  Static grasp Positioned by gravity  Dynamic grasp Positioned using accelerations

Nonprehensile Palmar Manipulation with a Mobile Robot By: W.Huang and G.Holden from RPI  Huang and Holden used a palmar robot with two degrees of freedom to pick up a box sitting on the floor pressed against a wall.  They used a Kinematic analysis to model the interaction between the box and the palm of the robot.

Non-prehensile conclusions  Focus on grasp-less manipulation because it requires less actuators, allows more degrees of freedom, and versatility is increased overall.  The downside is that planning, controllability, and programming become more complicated.

2.2 Excavation Methods   In order to set up a permanent habitat on the moon, trenches will need to be dug in order to cover important cables, protecting them from machinery and radiation from the sun.   Building a robotic machine to accomplish this task before astronauts arrive will save money and reduce risks involved.   A backhoe-type autonomous robot is one idea that could be used for many other tasks as well

Wheel Trench Cutter  A wheel with lots of scoops  In front, side, or behind  Many sizes of scoops

Bucket Excavator  Hydraulic arm with scoop attached to the end  Very popular

Chain Trencher  Similar to Wheel trencher  Uses steel teeth attached to a chain

Vibratory Plows  Creates a duct by vertically vibrating a plow blade.  Cable is laid into the duct

Excavation Conclusions  Bucket excavators are versatile but extremely difficult to control.  Trenchers/vibratory plow are very task specific and do not offer much versatility.

The Hardware Big Picture Computational Actuators Communication Sensors Power Supply 2.3 Microcontrollers

Distributed Computational System Main Controller (i.e.. Rabbit) Small controller, (i.e.. Basic Stamp) Sensor Actor Small controller Sensor Actor Small controller Sensor Actor Small controller Sensor Actor

Microcontroller Conclusions  Distributed calculation system is better than one strong and central system Redundancy, no real-time operating system necessary and available and well supported hardware available at the universityRedundancy, no real-time operating system necessary and available and well supported hardware available at the university  Use the microcontrollers available at the university Supporting persons available, controllers are cheap and fit our needs, specialized controller would not bring advantages that would over come increased costSupporting persons available, controllers are cheap and fit our needs, specialized controller would not bring advantages that would over come increased cost

2.4 Other Electrical Research  Autonomous Robotics  Robot Vision  Navigation  Inverse Kinematics  Robotic Control Systems  Decision Making Systems  USB Interface

3. Design Phase 3.1 Target Specifications 3.2 Tasks 3.3 Learning Tools 3.4 Field Experience 3.5 Soil Force Test

3.1 Target Specifications RankDescriptionCategorySpecUnit 1Trench depthExcavation6-10in 1 Trench lengthExcavation10m 1Soil sample sizeCollection3ft^ 3 2Object manipulation Strength10Kg 2Operating timePower1 taskW

3.2 Tasks  Top 5 in Bold  Soil Sample Collection  Trenching  Cable Laying  Rock Chipping  Soil Compaction  Dislodging  Rock Flipping  Path Clearing  Soil Relocating  Rock Pushing  Soil Sifting  Tilling  Stake Planting

3.3 Learning Tools  Robotic arm ◊Used to test and visualize motion and controllability of proposed design ◊Computer interface will allow us to test controllability using a programmable set of commands

3.3 Learning Tools  Boe Bot ◊Will give us experience working with continuous motion servos, microcontrollers, and programmability of each ◊Options to set up our own circuit for testing of sensors and other motors

3.4 Field Experience  We took a trip to Northern Idaho to get some hands-on experience with a back- hoe.  We learned that hydraulics are powerful, but would be a controls nightmare due to their nonlinear operation.  The Kinematics of an arm with four degrees of freedom would be too difficult to try to program in a one-year project.

Field Experience

Soil Force Test

4. Prototypes 4.1 Decision Process 4.2 Hole Saw Arm 4.3 Poker/Drill 4.4 Poker Arm 4.5 Sewing Machine 4.6 Sandlot Arm

4.1 Decision Process Prototype Decision Matrix AaronJenMattJasonVictorTotal Vic's all-n-one Arm with poker Bucket Hole Saw/drill Vibratory plow Sewing machine Sandlot/Spatula Conveyor belt Chain Trencher

4.2 Hole Saw

4.3 Poker/Drill

4.4 Poker Arm

4.5 Sewing Machine

4.6 Sandlot Arm

5. Initial Program Scripts 5.1 Flip a rock 5.2 Chip a rock

5.1 Flip a Rock This script uses the Sandlot Arm  Get to a rock  Send out ultrasonic signal  Receive back ultrasonic signal  Use algorithm to calculate distance from robot to rock  Lower Sandlot Arm to ground  Use linear motor to extend arm to the rock  Use ultrasonic signal and motor encoder signals to verify arm is at the rock  If arm is at rock, continue; if arm isn’t close enough move closer and repeat verification  Raise arm slightly off ground  Rotate arm 180˚  Use camera to take picture of flipped rock

5.2 Chip a Rock This script uses the Arm Poker  Get to a rock  Send out ultrasonic signal  Receive back ultrasonic signal  Use algorithm to calculate distance to rock  Position Poker Arm so that the poker is above rock  Use linear motor to strike down and chip the rock  Repeat strike motion once to make sure rock is chipped  Use a camera to take a picture of chipped rock.

6. Budget  Available………………………………………………...$7500  Research and learning……………………………$1000  Prototypes and testing………………………....$1000  Mechanical components and machining..$2000  Electrical components…………………………….$1500  Other…………………………………………….…………$500