Transcript Surveying Investigative Transportable Cartographical Helper? Sitchest Ish That Chu Heard? “…we’re going to retrofit it.”

Surveying Investigative Transportable Cartographical Helper?
Sitchest Ish That Chu Heard?
“…we’re going to retrofit it.”
Receiving
Sensory
Processing
Data
Storage
Transmitting
Motors
Transmit
Receive
Receive
Transmit
Transmit
Receive
ROBOT
BOOSTER
High-level
Functional
Diagram
USER
High Level Control: Commanding and
Processing Movement and
Environment
High-Level Software Design
Image processing
CPU
software
Mapping Database
Distance/ angle
BRAIN
Object
Ultrasonic
Sensors
Camera and
Laser
Spy Camera
ARM Cortex
M-3
Magnetometer
SPINE
Motor
Controller
ARM M-0
Spy Camera
Analog
Preprocessing
Circuit
Motors
Receiver
Remote
Control
Servo Motor
User
TV
Transmitter
Receiver
Ultrasonic Range Finder
Finds objects that may have been
missed by the laser.
 Allows basic object avoidance while the
rover is in motion.
 Model: LV-MaxSonar-EZ0


Status: Basic testing with Arduino-uno
completed – developing interface for M0
Cortex M-3
Handles image processing and location
awareness.
 Sends position data to lower level motor
control loops.


Status: Developing camera interface.
CMOS Camera
CMOS Schematic
EAGLE
Laser Range Finder Theory
Remember me?
This worked.
This Was Put Together
Calibration Data
Took Pictures
Quite Grainy, Similar to how the CMOS camera will see images
CMOS won’t have as many random colors
Applied a Sharpening Function
Quite
grainy
But the
spot is
brighter
After a Threshold Filter
21 Inches
measured
 56.97cm
calculated
 22.4291339
inches
 6% error

A Few Examples

91.44 cm
After

90.387 cm Calculated

-1.15% error
Tried to Expand to Line Laser
Not very bright
 Used water
 Different laser
on its way

Room For Improvement
A line is visible
 Not mapped to angles
 Lost data

 3 pts to 1

Great progress
 High level goal
 we have other options
Path Finding
To be implemented after scanning and
image processing.
 Initially, perform rudimentary scan and
move aimlessly between obstacles.
 Ultimately, be able to negotiate past
objects to reach a waypoint.

 This waypoint may be provided with vector data
from stored encoder/magnetometer data.
Status: In development.
Low Level Control: Providing Fine
Motor Control and Dead Reckoning
RC Receiver Waveforms
Zero point: Duty
Cycle is 8%
Minimum point:
Duty Cycle is
5%
Maximum point:
Duty Cycle is
11%
Wireless Decoding
Receiver’s output must be digitized and
encoded using the correct modulation
 ADC will be used to measure the output
of signal averager and output the
corresponding modulation to the motor
controllers

Schematic of the Signal Average
Circuit
ARM Cortex M-0
Separate chip chosen to diversify
processing abilities.
 Simple motor control option.
 Designed to handle control loops.
 Hope to guarantee high responsiveness
of all sensors, computer and control
systems.
 Specific Model: LPC1114FHN33/302
 Status: Initial development.

Distance Encoder
Basic device for measuring distance
travelled.
 Use paired IR LED/phototransistor and
ADC to measure pinwheel rotation.


Status: Hardware complete.
Distance Encoder Schematic
Motor Controller

Current design based on 2 banks of 4
redundant L298N with opto-isolation.
 Each chip handles 4 amps with 2 parallel H-
bridges.
 32 amp total current handling.
If revised, it will be printed on PCB and
based instead on H-bridge gate drivers
and power MOSFETs.
 Status: Fully functioning, but not ideal.

Motor Controller Schematic
Magnetometer






Digital 3-axis magnetometer.
Measures strength of magnetic field in
various directions with a highest field
measurement resolution of 0.015 µT
Precise angular position determined
through inverse tangent algorithm.
Communicates through I2C.
Accurately determines location and
orientation.
Status: Developing interface.
Magnetometer – Finer Details
Model No: LSM303DLH
 Breakout board from SparkFun

Power: Energizing Diverse Systems
Devices to Power on the Robot
Motor Controllers
 Radio Receivers and Video Transmitters
 Servo Motor (at least one)
 Processors
 Laser
 Cameras
 Magnetometer
 Ultrasonic Range Finder

Powering The Robot
Powered directly by a 7.4 V (2 cell)
Lithium Polymer Battery
 1st Choice - 6000mAh, 70C
 2nd Choice - 12000mAh, 40C
 3rd Choice – 2x 6000mAh, 30C

Powering Bot Movement
7.4V, XXX mAh, xxC
2 cell LiPo
Driver Motor
Controllers
Motors
5V Voltage Rail
Will be realized with a LM7805 voltage
regulator chip.
 Can supply up to 1.5 A of current


Status: Testing and laying out in Altium
3.3V Voltage Rail
Will be realized with a LM317 voltage
regulator chip
 Can supply up to 1.5 A of current


Status: Testing and laying out in Altium
3.3V Voltage Rail Schematic
MC34063A Chip – Boost Mode
Hi-Level Powering Diagram for Sensors
Batteries
Step-up
Voltage
Converter
(12V)
5 V Voltage
Rail
3.3V Voltage
Rail
Video
Transmitter
Ultrasonic
RC Receiver
ARM M-0
Cortex M-3
Magnetometer
Laser
CMOS
Camera
Power Consumption
Servo Motor



Unable to find
datasheet
Tested using
Arduino Uno,
collected
experimental data
Ready for
integration with M0
Servo PWM Signal Input
Vpp=~3.3V, f = 50Hz
Duty Cycle (%)
Angular Position
(degrees)
3.25
10
5.3
50
7.4
90
9.45
130
11.5
170
Switching Microprocessors



Cryptic sample code
Unhelpful documentation
Steep Learning Curve
C2000 Piccolo F28035



More intuitive
Useful sample code
Existing knowledge
ARM Cortex-M0
Progress with ARM Cortex-M0

Currently
 Sweeping PWM
 Working ADC test function

Goals
 Write functions to increase user control
 Communicate with other modules
Video Camera



Transmit video feed
From Amazon, lacks
documentation
Status: Transmitter
+ Receiver work –
now we need to
interface power
supply and camera
PCB
Plan to lay out a board containing
voltage rails and the boost converter
 In the future include an ARM Cortex M0.
 Finalizing first draft of this PCB before
the end of this week

Planning: What the future holds
Design Goals
Module
Low
Medium
High
Power
-Buy Chips
-Etch PCB
-Buy Controllers
-Design Converters
-Design all
Sensing
-Stereoscopic
-Single Laser and
Camera
-Line laser
Image
Processing
-Stereoscopic
-Distance and angle
from single laser
-From line laser
Board Layout
-Etch analog
control circuit
-Print control circuit
-2 processors 1 board
Motors
-Elbow grease
-Servo Motor moving
sensor
-Moving 2 dimensions
µproccessing
-RC Analog
-ARM or FPGA
-2 ARM processors
Booster
-None
-Increase operating
range
-Multiple boosters
Collision
Sensing
-None
-Ultrasonic
-None
Milestones and Expo

Milestone 1:
 RC control
 Motor drivers
 Magnetometer

Milestone 2:
 Laser range finding tower
 Ultrasonic

Expo:
 Path finding
Current Development
Finalize first revision of PCB
 Start constructing the mounts for the
laser range finder and motor drivers
 Integrate motor drivers with the M-0
control and batteries

Budget