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Aziz Albander Matt Certosimo Albert Como Vincent Din Lex Telischak Tyler Troup. S.I.T.C.H. Overview. Design of a semiautonomous robot Transmits video feed back to user Drops relay module for extended range Utilizes laser range finder to navigate unobstructed return path
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Aziz Albander Matt Certosimo Albert Como Vincent Din Lex Telischak Tyler Troup S.I.T.C.H.
Overview • Design of a semiautonomous robot • Transmits video feed back to user • Drops relay module for extended range • Utilizes laser range finder to navigate unobstructed return path • Pre-constructed robot chassis
Objectives • Implement remote control • Equip rover with laser range finder: • Object Detection • Path finding • 1500mW, 2.4GHz video transmission • Top roving speed at least 2mph • 640x480 video resolution • Hopeful for 100m navigation range
Power Supply • The goal of the power supply system is to provide all the loads with necessary power level • Batteries and separate control circuits will be used for each subsystem • We are still undecided if we want to design and build converters or if we are going to buy power management chips from TI
At low level: • Buying a DC/DC convertor to divide the power through out the circuit • Getting all the devices on an etched circuit board At medium level: • Buying the controller and design the buck DC/DC convertor At high level: • Design the controllers that control the power on the circuit and design the convertors to divide the power throughout the system
Robot Power Supply DC motors with brass brushes and 75:1 steel gearboxes Driver Motor Controllers Processor DC Batteries Sensors Motor for Camera Motor Controllers
Receiving Sensory Processing Transmitting Data Storage Motors Transmit Receive ROBOT BOOSTER Receive Transmit High-level System Block Diagram USER Transmit Receive
Laser Range Finder Theory But what is “tan θ” ? (1)
Finding The Angle To find the angle used in the distance equation a few things may be needed: What pixel is the brightest on the camera? How far is that pixel from the horizon? How many radians per pixel pitch? (1) Number of pixels can be counted from the center of the focal plane The other parameters will be found by calibration table: (1) (1)
Beam Shaping with Cylindrical Lenses • Spreading the beam horizontally will allow for more distances to be calculated at a time (2)
Beam Shaping • Can be done with a cylinder of water
A different Range finding option (3) Professor Siewert’s description of machine vision in his real-time imbedded systems book Uses two cameras Still finds distance Cons: Pro: Computationally more intensive More support available if we get stuck
Image Processing Options • Brightest pixel • Single distance • Line of bright pixels • Multitude of distances
Math Laser Fix focal length Measure beam diameter Determine beam spread in 1 dimension Determine
Board Layout Goal – Low • We plan on etching our own analog control circuits for the motors • Kits are available from Jameco.com that allow us to etch at least 5 circuits for under 45$ (4)
Board Layout Goal – Medium + High (5) • We plan on utilizing Altium to layout a digital control circuit • Then our designs will be sent to Advanced Circuits in Aurora to generate a PCB • For our high level goal we plan on printing multiple processors on one board (6)
Motors - Low • No motors • Manual control
Motors - Medium • Use of single servo motor • Horizontal Direction
Motors – High • Use of dual servo motors • Horizontal and vertical directions • Implementation • Motors connected
Processing – the Possibilities (7) (8) FPGA Cyclone II ARM Cortex-M0 We may even use a combination of the two types
Processing: RC control • RC control requires basic processing • PPM signal must be analyzed by a processor • Processor must provide a combination of PWM and digital signals (9)
Processing: Preparations for Autonomy • Sensor data must be made sense of • Sensors include a laser range finder and encoder • Data from these sensors must be interpreted (10)
Processing: Full autonomy. • When all sensor systems are functional • Use the laser range finder to generate a map • Use encoder to track position in said map • Use map data to find paths (11)
Signal Booster - Medium Level • RC and processed video signals must be relayed back and forth between both the S.I.T.C.H. and the booster module along with the S.I.T.C.H. and the user • Signal must be boosted to increase the range of operation and communication of the S.I.T.C.H. • The S.I.T.C.H. should be able to return to the user without ever losing signal
Signal Booster - High Level • The Signal Booster will also have filtering capabilities, allowing us to increase our signal-to-noise ratio • Implement the use of multiple signal boosters, allowing the S.I.T.C.H. to continue past the range of the initial signal booster
Collision Detection • Implemented using either an ultrasonic range finder and/or a collision detecting bumper
Collision Sensor • The input of the sensor is the sensing of an obstacle • The output of the sensor is a signal sent to the processor in order for the processor to make and decision and tell the motors to react accordingly • Functional description: When an obstacle is detected the sensor will send a signal to the processor and then the system will know a collision is about to occur and take proper action to avoid the object • Test plan: We are going to test the sensor by placing an object in front of the sensor and measuring the resulting voltage
Collision avoidance • This ultrasonic range finder: • Detect objects directly in front of it • Can stop robot from hitting stray cats and children • Real time
Collision avoidance • Bumper • Hits something and reverses
A jumping off point Things that must work
We have already purchased and received this chassis.. Dagu Wild Thumper 4WD All-Terrain Chassis – Chrome
Robots Motors • Implement motor controllers for the 4 DC motors with brass brushes and 75:1 steel gearboxes to control the robot’s movements
Risk: Initial Motor Current Spike Solution: Opto-isolation Chips • Each of the 4 motors on the robot has its own controller, therefore we will need at least 4 opto-isolation chips to protect the motor controllers • Need 6 Channels minimum; undecided if we want 4 3-Channel chips or 12 1-Channel chips • Depends heavily on available board space
Safety Concerns • Laser Danger • RF Exposure • Possibility of Collision • Small children
8 CH Wireless Audio Video 2.4 GHz 1500 mW Transmitter and Receiver Kit Wireless video transmission – Safergaurd.com
RC 4 channel control • RC control signal generators • Transmitter