Using the art of biomimetics, ArachnoBotics Research Inc. is proud to present its proposal for ArachnoBot™, a lightweight robotic spider. The ArachnoBot™ is based on a project commissioned by the European Space Agency (ESA) whose main aim is to design a spider robot prototype to be used in outer space travel. Its small, lightweight form factor is based on both the weight requirement for launching it into space, as well as that of its biological counterpart: the Arachnid

ArachnoBotics Research Inc.

Bloch, Pavel

Gupta, Pranav

Naaykens, Daniel

Panaitu, Cristian

Strbac, Stefan

Simon Fraser University Institutional Repository

ArachnoBotics	Research	Inc.	The ArachnoBot™Simon Fraser UniversityFaculty of Applied ScienceSchool of Engineering Science440/305 Capstone Project by:Daniel NaaykensPavel BlochPranav GuptaStefan Strbac2Project Introduction! The ArachnoBot! Lightweight Robotic Hexapod! Initial Prototype! Based on European Space Agency Project! Intended for Space Exploration3Presentation Overview! Project Background! System Overview! Demonstration! System Design! Market Analysis! Reflections! Conclusion4Team Introduction! Daniel Naaykens! Mechanical Design! Pavel Bloch! Electronics Design! Pranav Gupta! FPGA Design! Stefan Strbac! FPGA and PCB Layout5Project BackgroundEuropean Space AgencyBiomimeticsMobile Robotics6European Space Agency! Based on a project by the European Space Agency! Fleet of small and lightweight mobile robots! Explore planets! Maintain mechanical systems! Construct human outposts! ArachnoBot furthered this idea for any exploration7Biomimetics! Nature has evolved creative solutions to many problems! Even solutions for devices that have not been invented! Powerful creative force in mimicking biology! Multi-legged walk cycles for walking, running, climbing! Flight, swimming, defense mechanisms8Mobile Robotics! Study of robots capable of locomotion! Locomotion can be powered bya number of ways! Wheels, Legs, Sliders, Flight, Swimming! Sensors and actuators! Central processing unit! Electrical components9System OverviewElectromechanical ComponentsProcessing Components10Functional Diagram11State	Indicators Robot	MovementUser	Inputs	and	Programming Power	Distribution	External	Power	Supply	Electromechanical	System	ComponentsControl	System	ComponentsDC	motorsAngle	SensorsSystem	Memory	Signal	ProcessingMotor	DriversPWMControllerInput	BuffersSensors! Used to determine each joint’s position! Small rotary potentiometers! Design considerations included friction, size, and accuracy12Actuators! Used to move each joint! Geared DC motors! Design considerations included friction, torque, and speed13Mechanical Body! Made of Rapid Prototyping material! Replaceable! Easily constructible! Take wire routing into account ! Lightweight yet strong14Processing Components! FPGA Development Board! MicroBlaze architecture! Multi-core processing environment! Allows parallelization of tasks! Each leg has its own MicroBlaze in conjunction with the master controller15DemonstrationComputer Interfaced Trajectory TraversalHorizontal WalkingUntethered MovementSystem DesignElectronic ComponentsPCB DesignMechanical ComponentsCentral Processing17General Design! Aesthetically pleasing! Total weight       ! Total dimensions: 16cm x 16cm x 12cm18Electronic Components! Single common 5V power supply! Main switching voltage regulator 3.3V (up to 6A)! Supports use of external power supply for motors! Cable length > 1m19Electronic Components20Motion generation overviewElectronic ComponentsMotor Control:! FPGA PWM generator core! 6 Quad H-Bridge Motor Driver (1 per leg)Feedback Loop:! Xilinx XPS-Delta-Sigma-ADC Core! 5 Quad IC Comparators (20 comparators for 18 joints)! 18 RC filters21PCB DesignPCB Features:! 5V in  /3.3V out (6A) voltage regulator! PCB design & layout with Altium Designer Suite! PCB manufacturing at Enigma Interconnect22PCB Design23PCB Design24Mechanical Design! Parts designed in SolidWorks! Printed using SFU’s Rapid Prototyping Machine! Several Revisions25Final Mechanical Design! 1 cm larger than proposed! Includes a small notch for wire routing on the thigh! Large areas removed from frame in order to reduce weight26Central Processing! FPGA – Field Programmable Gate Array! Integrated circuit configurable by the user after manufacturing ! Configured using a Hardware Description Language (HDL)! FPGA comes prepackaged on module with breakaway pins27Central ProcessingAdvantages of FPGA module versus microcontrollers:! 1 FPGA versus 7 microcontrollers (complicated interface)! Lower power consumption! More design flexibility! Adding complexity does not affect size/weight! Simpler PCB design! Do not need external ADCs and MUX outputs28Central Processing2986 mm54mmXCM-016 HUMANDATA  Xilinx Spartan 3A FPGA ModuleCentral Processing30Internal FPGA systemCentral Processing31Leg control subsystemSoftware! ADC reads in angle! Formula converts it into degrees! Determines and adjusts motor positions! Uses PID control to increase torque to the motor under high load! PWM control to the motor drivers.32PCB Interface! Interfaces all components! Critical in it’s operation, includes backups such as overload protection and fuses! Provides power to all components through a 5V – 3.3V DC-DC Converter33Control Algorithm34Control Algorithm35Xilinx XPS-Delta-Sigma ADCControl Algorithm! FPGA monitors the current angle of each joint! Then determines the necessary direction of travel to reach a desired angle! Once the desired angle has been reached, the FPGA keeps the joint at that position through proportional feedback control! Future work will include PID control of the motors36Trajectory Generation! Generated a simple walk cycle to move the ArachnoBot™ 1 cm forward! Each leg rises 1 cm, and then lowers to the ground! Ground position determined through Visual Nastran, which performs inverse kinematics! Inverse Kinematics determines joint angles for a given trajectory37Construction Process38Construction Process39Construction Process40Construction Process41Construction Process42Final Result43Reliability! Reproducibility! Prototype material for frame and legs! Redundancy! Quad Motor Drivers have spare port! Separate power rails and separable power supplies for        motors ! Reparability! Every component can be detached! Modular design44Market AnalysisMarket SegmentPossible CompetitorsArachnoBot™ AdvantagesProduct Cost45Market Segment! Arachnobot ™ version 1 is a prototype for a robotic spider intended for space exploration and research.Version 3 of the design is intended for the following markets:! Space Research & Exploration! European Space Agency (ESA)! Canadian Space Agency (CSA)! National Aeronautics and Space Administration (NASA)! Other uses may include land exploration, and university research.46Similar ProductsSeveral similar robotic platforms exist for our prototype:! HiBot Roller Walker ! 4-Leg platform allowing walking, and skating using servos! http://www.hibot.co.jp/html/webapps/top.php?lang=en! Lynxmotion CH3-R Combo Kit! Features 3DOF Leg design, and servo motor controllers! http://www.lynxmotion.com/Category.aspx?CategoryID=347ArachnoBot™ Advantages! Allows additional functionality to design! Eg, Bluetooth for wireless trajectory control! Artificial Intelligence!  Allows tweaking of motor control! Design is highly modular ! Can switch components48Product Costs! Our product costs – production and retail! Comparison with other competiton! Lynxmotion CH3-R Combo Kit ~$800 CAD, AH3-R Combo Kit ~$1200 CAD (www.lynxmotion.com)49   Arachnobot Unit       Arachnobot Mass Prod Lynxmotion CH3-RCost Retail PriceCost Retail Price Retail PriceExoskeleton $500 $50FPGA module 450 100PCB 400 50Motors 306 100Total Product $1656 $300Labour $2000* $200**Total Cost $3,656 $5000 $500 $1000 $12002 jr. engineers * 40hrs/week *$25/hr=$2000 **Assume mass assembly requires 4 hrs/unitReflectionsBudgetTimelineLessons LearnedFuture WorkAcknowledgements50BudgetPart Proposed ActualFPGA Development Board $200.00 $450.00Xilinx JTAG Cable $0 $350Printed Circuit Board Manufacturing $1000.00 Donated ($1200)Rapid Prototyping $100.00 Donated ($1500)Sensors $200.00 $150Motors $250 $600Circuit Elements $400.00 $500Contingency $150.00 $0Final $2,300.00 $4750Difference: $245051Timeline52DOCUMENTATION AND DELIVERABLESMechanical ConstructionProto-board ConstructionMechanical TestingSoftware TestingINTEGRATION AND COMPLETIONEstimatedRealizedLessons LearnedTeam Dynamics:! Scheduling conflicts need to be resolved early! Well defined roles and responsibilities are important! Efficient teamwork is critical! Communication is crucial53Lessons LearnedProject Development:! Order parts early, purchase in bulk, and buy extra! Budget for a larger contingency, especially for debugging! Rapid Prototyping errors happen! Create test plan, run tests that are likely to create errors first! Test entire system integration first, even if subsystems are not in their final versions 54Future Work! Wireless control walking, battery power! Vertical climbing! Use PCB as base frame to reduce weight! Thinner and lighter exoskeleton! Anything else? ****55Acknowledgements! Dr. Carlo Menon! Dr. Lesley Shannon! Cristian Panaitiu! Lucky One and Fred Heep! John Parsons (Enigma Interconnect)! Yasong Li, Ausama Ahmed, and Juan Pablo Diaz Tellez! Andrew Rawicz and Steve Whitmore! Pranil Reddy! ESSEF56Conclusion57Conclusion! Proof of concept accomplished!! In retrospect, FPGA was the right choice for processor! Most functional specs met or nearly met58ArachnoBotics	Research	Inc.	

ArachnoBot [lightweight robotic spider]

http://summit.sfu.ca/system/files/iritems1/22003/10demo.pdf

ArachnoBot [lightweight robotic spider]

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Simon Fraser University Institutional Repository