Corporation 4 NASA Project Manager Phillip Young Presenting Joe Bryant and Bryant Hains Outline Electrical Engineering Progress Report Project Management Systems Engineering SE Architecture and Design Bucket Subsystem Linkage Subsystem Frame Subsystem Systems Engineering Verification and Validation EE Schedule Phase One Determine subsystems Design subsystems Prototype Test subsystems Phase Two Implement Phase One subsystems onto existing excavator Design any interfacing circuits Transistor switch Voltage regulator Interface Diagram Salvage of Old Excavator Mechanical Rework Welding Platform Electrical Rework Fix Purchase components Test components for functionality Create interface between microcontroller and motors actuators Test interfaces for functionality Status for Old Excavator Have completed the initial mechanical fixes for old excavator Have ordered necessary parts to get actuators operating In the progress Going through different designs for interfaces for the actuators Project Management Presentation Goals 1 To define the project in enough detail at all levels system subsystem and components to establish a Preliminary Design that has no unresolved design or technology issues 2 Establish the basis for proceeding with detailed design Show that the correct design option has been selected Interfaces have been identified Verification methods have been established Project Management cont Management Structure Program Manager Dr Beale Subsystem Bucket Frame Linkage Total Project Manager Phillip Young Frame Subsystem Lead Alan Gaskins Bucket Subsystem Lead JD Jenkins Cost Budget Linkages Subsystem Lead Bryant Hains Estimated Cost Budget 670 1070 413 2123 Estimated Weight Budget 40 kg 40 kg 20 kg 100 kg Project Management cont Milestones Project Management cont SE Mission Objectives Mission Statement Create a tele operated lunar harvester prototype targeting less than 150 W power usage and weighing less than 100 kg for studies on the earth fulfilling environmental requirements of the moon Mission Level Requirements Shall be designed to conduct studies on earth but be able to operate in a Lunar environment Shall interface with KSC Interfacing Plate Shall be operated remotely Shall collect and hold at least 50 kg soil per hour SE Concept of Operation i Soil pan to harvest position scrape soil from behind chariot in lane like fashion until bucket reaches capacity ii Soil pan to transport position chariot rover returns to collection point with soil pan pulled behind only surface contact is soil pan wheels iii Chariot rover up and over soil ramp to position soil pan over hopper opening iv Soil pan to dump position empty bucket contents into hopper v Soil pan to transport position return to harvest area vi Soil pan to harvest position begin scrape process SE Architecture and Design Working Model Analysis Dumping Position Harvesting Position Transporting Position SE Architecture and Design Lunar Harvester Bucket Frame Blade Wheel Structure Container Rover Interface Bucket Linkages Interface Isometric View Full Assembly Linkages Linear Actuator Pivot Bar Transfer Bar Rotational Bar Bucket Subsystem Derived Requirements Functional 1 Shall be designed to accommodate flow of regolith during dumping 2 Shall provide a method of keeping regolith from spilling during transport 3 Shall have a angled back wall to aid in harvesting and dumping Performance 1 Shall hold 50 kg of soil V 1 04 ft3 2 Shall be able to accommodate a cutting blade mounted on the front edge of the bucket Bucket Subsystem cont Calculations The following values were set or assumed for these calculations Max Load 75kg Max Volume 1 56 ft3 Width of the bucket 1 5 ft Trapezoidal Area of Bucket V w 1 0387 ft2 Angle of incline of rear of bucket 60 A b1 b1 h 2 b1 h 60 Height ft Average Base ft Total Length ft Smaller Base ft Ratio Width Length 0 5 2 0774 2 59675 1 55805 0 577645133 0 6 1 731166667 2 163958333 1 298375 0 69317416 0 7 1 483857143 1 854821429 1 112892857 0 808703187 0 8 1 298375 1 62296875 0 97378125 0 924232213 0 9 1 154111111 1 442638889 0 865583333 1 03976124 1 1 0387 1 298375 0 779025 1 155290267 1 1 0 944272727 1 180340909 0 708204545 1 270819293 1 2 0 865583333 1 081979167 0 6491875 1 38634832 1 3 0 799 0 99875 0 59925 1 501877347 1 4 0 741928571 0 927410714 0 556446429 1 617406373 1 5 0 692466667 0 865583333 0 51935 1 7329354 Height in Average Base in Total Length in Smaller Base in 12 12 4644 15 5805 9 3483 To account for wall thickness simplify dimensions and to adjust for proportionalities the following dimensions were chosen This resulted in the volume and angle being slightly different than the values set for initial calculations Height in Average Base in Total Length in Smaller Base in 10 15 17 13 b2 Bucket Subsystem cont Bucket Subsystem cont Engineering Analysis Force analysis ongoing McKeys and Ali Zeng models Bill of Materials No 1 2 3 4 5 Part Bucket Components Qty 3 Bolt Nut Washer Blade Metal Block 15 15 15 1 Description 24 x 24 Aluminum Alloy Sheet Metal 1 4 20 Bolt 1 4 20 Nut 1 4 20 Washer 36 x 4 x 2 Aluminum Block Estimated Cost 450 10 5 5 200 Linkage Subsystem Derived Requirements 1 Shall be able to move bucket into the three desired mechanical positions 2 Shall be powered by motorized actuator 3 Shall provide mechanical advantage in operating bucket 4 Shall constrain bucket movement to safe bounds Linkages Subsystem cont Transport Position Pivot Bar Force Transfer Bar Actuator extended to half stroke Stable level position to carry soil Rotational Bar Ground Bar Linkages Subsystem cont Harvest Position Actuator fully contracted Bucket orientation sloped to facilitate soil movement Linkages form near isosceles triangle for strength Linkages Subsystem cont Dumping Position Actuator extended to full stroke Main Links close to parallel Bucket near vertical to facilitate soil removal Link Subsystem cont Point O Rigid Load Bearing Factuator Fblade Harvesting Position Representation of Forces Link Subsystem Cont Actuator Options Linear Cylinder Linear Slide better force management Linkages Subsystem cont Bill of Materials No Part 1 2 3 4 Rotational Bar Force Transfer Bar Pivot Bar Linear Actuator 5 6 7 Bolt Nut Washer Qty 2 2 2 2 10 10 10 Description 12 x 3 x 1 Aluminum Block 12 x 3 x 1 Aluminum Block 24 x 3 x 1 Aluminum Block 18 Stroke Tubular Actuator 150 lbs force 1 4 20 Hex Bolt 1 4 20 Hex Nut 1 4 20 Washer Estimated Cost 60 60 80 200 7 3 3 Frame Subsystem Derived Requirements 1 Shall be able to