1 / 83

Quad-Copter

Quad-Copter. Group 3 Fall 2010. David Malgoza  Engers F Davance Mercedes               Stephen Smith Joshua West. Project Description. Design a flying robot Robot must be able to: Avoid Obstacles Navigate to GPS location Communicate Wirelessly Wireless Manual Control

abie
Download Presentation

Quad-Copter

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Quad-Copter Group 3 Fall 2010 David Malgoza  Engers F Davance Mercedes               Stephen Smith Joshua West

  2. Project Description • Design a flying robot • Robot must be able to: • Avoid Obstacles • Navigate to GPS location • Communicate Wirelessly • Wireless Manual Control • Stream Wireless Video

  3. Project Motivation The Big Question, WHY? • Wanted to design an aerial vehicle for surveillance purposes • Wanted to do a project with fair amount of hardware and software • Most of all wanted to do something cool and fun!

  4. Project Overview To do this we must: • Design and code a control system for the Quad-Copter (move up, avoid this, etc…) • Design and code a sensor fusion algorithm for keeping the copter stable • Design and code a wireless communication system (send commands) • Design and build a power distribution system • Design and build a chassis

  5. Goals/Objectives • FLY • The Quad-copter must be able to remain stable and balance itself. • The copter must be able to move forward, rotate left and right, rise and descend • The copter must be able to signal when power is running low (audible)

  6. Specifications/Requirements • Lift at least 2 kg of mass • Navigation accuracy within 3m • The Quad-Copter must communicate wirelessly at least 100m • The Quad-Copter must flight for a minimum of 5 minutes • The Quad-Copter must be able to detect objects from at least 18 inches away • The Quad-Copter must have video capabilities at 100m

  7. Quad-Copter Concept

  8. Frame

  9. Frame Goals: • Create a lightweight chassis for the Quad-Copter • The chassis must support all batteries, external sensors, motors, and the main board • Cost Effective Requirements: • Create a chassis with a mass of 800g or less • The area the Quad-Copter cannot exceed a radius of 18in. • Must be able to support at least a 1.2kg load

  10. Materials Comparison • There were 2 lightweight materials we considered for the chassis: Aluminum and Carbon Fiber • Both have capabilities of being entirely used as a chassis and meet the maximum mass requirements

  11. Design of Frame • 2 aluminum square plates will be used as the main structural support • 4 rods will be screwed to the top square plate at and secured at the corners • Below the 2 plates, a lower plate will be placed 1.5in below to support all batteries, as well as secure the range finder sensors and video system • Landing gear will be shaped as standard helicopter legs. • A layer of foam will be used for padding the landing gear

  12. Diagram of Frame

  13. Motors/ESC

  14. Motors Goals: • To use lightweight motors for flight • The motors must be cost effective Requirements: • Use motors with a total mass of 300g • Each motor must be able to go above 2700 rpm • Each motor is to be controlled via PWM signal from the processor

  15. Brushless Motor • Advantages • Less friction on the rotor • Typically faster RPM. • PWM or I2C controlled by an electronic speed control (ESC) module. • Disadvantages • Require more power. • Sensorless motors are the standard • Typically more expensive

  16. TowerPro 2410-09Y BLDC • Minimum required voltage: 10.5V • Continuous Current: 8.4A • Maximum Burst Current: 13.8A • Mass: 55g • Speed/Voltage Constant: 840 rpm/V • Sensorless ESC required for operation.

  17. Sensorless ESC • The ESC translates a PWM signal from the microprocessor into a three-phase signal, otherwise known as an inverter. • Based on a duty cycle between 10% and 20%, the ESC will have operation. • Based on the requirements given by the manufacturer, the PWM frequency will be 50Hz.

  18. Power Supply System

  19. Power Goals and Objectives: The ability to efficiently and safely deliver power to all of the components of the quadcopter. Requirements: The total mass of the batteries should be no more than 500g A total of 3 low-power regulators are to be used. Must be able to sustain flight for more than 5 minutes

  20. Batteries

  21. LiPo Battery Specifications on the EM-35 • Rated at 11.1V • Charge Capacity: 2200mAH • Continuous Discharge: 35C, which delivers 77A, typically. • Mass: 195g

  22. Power Distribution Digital Compass 6V – 4 AA LM7805 GPS Main Processor LD1117V33 Wireless Processor Transceiver 11.1V LiPo Motor LM317 Ultrasonic Motor Ultrasonic 11.1V LiPo Motor Gyroscope Accel. Motor

  23. LM7805 • 5V LDO regulator, rated at 1A maximum. • The LM7805 regulator is used for the GPS, the main processor, and the digital compass module. • 300mA required for all components.

  24. LD1117V33 • 3.3V LDO regulator, with 500mA maximum. • Will be used for powering the transceiver and the wireless system, and most of the analog components.

  25. LM317 • The regulator has a maximum current rating of 1A. • TO-220 packaging is preferred if the application of a heat sink is later required. • This will be used as a 3-V regulator for the gyroscope.

  26. Logic Converter • Allows for step-up and step-down in voltage when data travels between a lower referenced voltage signal to a higher referenced voltage signal. • This will be used to communicate the GPS and the wireless communication system with the main processor

  27. Sensors

  28. Sensor Subsystems/Functions • Flight stability sensors • Monitor, correct tilt • Proximity sensors • Detect obstacles, ground at low altitude • High altitude sensor • When higher than proximity sensor range • Direction/Yaw sensor • Maintain stable heading, establish flight path • Navigation/Location sensor • Monitor position, establish flight path *Minimize cost and weight for all choices

  29. Flight Stability Sensors • Goals/Objectives • A sensor system is needed to detect/correct the roll and pitch of the quad-copter, to maintain a steady hover. • Specifications/Requirements • Operational range 3.0 – 3.3 V supply • Weigh less than 25 grams • Operate at a minimum rate of 10 Hz

  30. Flight Stability Sensors • Options (one or more) • Infrared horizon sensing • Expensive, unpractical, interesting • Magnetometer (3-axis) • Better for heading than tilt, little expensive • Accelerometer • Measures g-force, magnitude and direction • Gyroscope • Measure angular rotation about axes

  31. Flight Stability Sensors • IMU (Inertial Measurement Unit) • Combination of accelerometer and gyroscope • ADXL335 - triple axis accelerometer (X, Y, Z) • Analog Devices • IDG500 – dual axis gyroscope (X and Y) • InvenSense • 5 DoF (Degrees of Freedom) IMU • Sensor fusion algorithm • Combines sensor outputs into weighted average • More accurate than 1 type of sensor

  32. IMU Hardware • ADXL335 - triple axis accelerometer • +/- 3 g range – adequate • 50 Hz bandwidth – adequate, adjustable • 1.8 – 3.6 V supply • Analog output • IDG500 – dual axis gyroscope • Measures +/- 500 º/s angular rate • 2 mV/deg/s sensitivity • 2.7 – 3.3 V supply • Analog output

  33. ADXL335 – PCB Layout • Surface mount soldered to main PCB • 3.3 V supply filtered by .1µf cap • .1µf caps at C2, C3, C4 that filter > 50Hz • X, Y, Z outputs to MCU A/D converters • S1 self test switch

  34. IDG500 – Board Layout • Soldered to main PCB • 3.0V supply • X & Y gyro outputs with low pass filter, to A/D • C5-C6 for internal regulation

  35. IMU – Algorithm Overview • Accelerometer vector R projected onto the xz and yz planes forms angles Axz and Ayz (yellow), which represent current tilt • Gyro yields instantaneousvelocity and direction of the same angles at regular interval T • Results merged into an improved estimated angular state • The algorithm’s outputis the input to the linearcontrol system

  36. IMU – code progress • IMU simulation in C • Calculates improved angular estimation from simulated 12-bit A/D outputs • Lacks port definitions, timing constraints

  37. Proximity Sensors • Goals/Objectives • Reliably detect different shapes, surfaces • Under various light and noise conditions • One facing down, one facing forward • Specifications/Requirements • Detect the ground at 1-15 feet • Obstacles 30˚ arc forward 1- 8 feet • 6 inches resolution

  38. Proximity Sensors • Options • Infrared proximity sensor • Cheap, ineffective in sunlight • Laser range finder • Too expensive • Ultrasonic range finder • Affordable • Reliable • Good range

  39. Ultrasonic range finder • Maxbotix LV-EZ2 • $27.95 each • 1 inch resolution • Max range 20 feet • Detection area depends on voltage, target shape • person ≈ 8 ft. • wall ≈ 20 ft. • wire ≈ 2-3 ft.

  40. Ultrasonic – Board Layout • 3 header pins on PCB • 3.3 V supply • Output to A/D • Analog ground • Low pass filter • Reduce noise • 100 uf cap, 100Ω res. • 6 – 12 inches wire • front sensor must have clear field i.e. no interference from propeller

  41. High altitude Measurement • Goals/Objectives • Measure higher altitudes, beyond the range of the ultrasonic sensor • Ensure that the copter stays under control • Quad-copter could fly beyond radio control range • AI protocol to limit altitude • Overridden by ultrasonic when applicable • Requirements/Specifications • Measure Altitude from 15 – 200 ft. • 10 ft. or better resolution/accuracy

  42. Options: GPS vertical component unreliable Barometric altimeter Determines altitude from air pressure More effective at higher altitudes Won’t recognize uneven ground HDPM01 – Hoperf Electronic dual function altimeter/compass module with breakout board Cost efficient solution $19.90 vs. $45.00 (separate) High altitude Measurement

  43. Direction sensor (Compass) • Goals/Objectives • Establish an external reference to direction • For maintaining a stable heading, turning, and establishing a flight path in autonomous mode • The module should not suffer from excessive magnetic interference (compass) • The module should be separate so that it can be placed away from interfering fields and metals (compass) • Specifications/Requirements • Accurate to within 3 degrees

  44. HDPM01 – Board layout • 6 header pins from PCB • Supply at 5 V • Digital ground • Master clock • I2C serial data line • I2C serial clock line • XCLR – A/D reset • Pull-up resistors • High to transfer

  45. Navigation/Location sensor (GPS) • Goals/Objectives • Needed for autonomous flight mode • The system should establish an external reference to position (latitude and longitude) • The system should have a serial output compatible with the MCU, UART preferred. • Should be compact, requiring minimal external support (internal antenna) • Requirements/Specifications: • The system should be accurate to within 3 meters (latitude and longitude). • The update rate should be at least 1Hz.

  46. Navigation/Location sensor (GPS) • Options • No practical alternative to GPS module • With a GPS system, the quad-copter can autonomously move toward a given coordinate • And, return to point of origin • MediaTek MT3329 GPS 10Hz • $39.95 for module + adapter (special offer) • Integrated patch antenna (6 grams total) • 1-10 Hz update rate • UART interface

  47. MT3329 GPS Module • MediaTek chip • Sensitivity: Up to -165 dBm tracking • Position Accuracy: < 3m • Coding/Library support available from DIYdrones • Adapter board (wired to main PCB) • Facilitates testing, easily switched from prototype board to final board • Backup battery • LED: blinks when searching, lit when locked

  48. MT3329 – Board Layout • Main PCB will have an EM406 connector (6 pins) • Rx and Tx to MCU • 5.0 V supply, 3.0 V enable, digital ground • 20 cm EM406 compatible connector cable • Module can be attached to the frame (tape/Velcro)

  49. Microcontroller

  50. Goals/Objectives • Able to produce PWM signal • Send/Receive UART signals • Hardware ADCs not just comparators • I2C capability • 16-bit timers with 4 output compare registers • 2 UART ports • 8 ADC ports (minimum 10-bit accuracy) Specifications/Requirements

More Related