system draft - isy.liu.se€¦ · system draft editor: marcus b ack version 1.0 status reviewed...
TRANSCRIPT
System Draft
Editor: Marcus Back
Version 1.0
Status
Reviewed Martin Szilassy 2014-09-19Approved Hanna Nyqvist 2014-09-19
Autonomous mine sweeper: BalrogLiTH
2014-09-19
PROJECT IDENTITY2014/HT, Invenire Periculosa
Linkoping University, Dept. of Electrical Engineering (ISY)
Group membersName Responsibility Phone Email
(@student.liu.se)
Martin Szilassy(MS) Project manager (PM) 070-8840295 marsz918Marcus Back(MB) Responsible for docu-
mentation (DOC)070-6924804 marba751
Victoria Alsen (VA) Chief of tests 073-9409540 vical845Johan Kallstrom (JK) Chief of design 073-0718371 johka546Mikael Hammar (MH) Master of SLAM 070-2658294 mikha087
Daniel Orn (DO) Chief of hardware 073-6448910 danor434Olof Zetterlund (OZ) Chief of information 073-7133822 oloze183Simon Ollander (SO) Internal advisor 073-8322898 simol515
Email list to the whole group: [email protected] site: http://www.isy.liu.se/edu/projekt/tsrt10/2014/bandvagn/
Customer: SAAB Bofors Dynamics, LinkopingCustomer contact: Torbjorn Crona, [email protected]
Course leader: Daniel Axehill, +46 13 284042, [email protected]: Hanna Nyqvist, +46 13 281 353, [email protected]: Martin Lindfors, +46 13 281365, [email protected]
TSRT10Marcus Back
Invenire [email protected]
LipsPage i
Autonomous mine sweeper: BalrogLiTH
2014-09-19
Contents
Document history iv
1 Introduction 1
1.1 Overview of the system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Definition of terms . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2 Subsystem 1 - Base station 3
2.1 Overview of the subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.2 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.3 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
2.4 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . . . . . 3
3 Subsystem 2 - Balrog 4
3.1 Overview of the subsystem . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
3.2 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.3 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.4 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . . . . . 5
3.5 Balrog subsystem - Hand controller . . . . . . . . . . . . . . . . . . . . . . 6
3.5.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.5.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.5.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 6
3.6 Balrog subsystem - Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.6.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.6.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
3.6.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 7
3.7 Balrog subsystem - Propulsion . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.7.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.7.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.7.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 7
3.8 Balrog subsystem - Positioning and mapping . . . . . . . . . . . . . . . . . 7
3.8.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3.8.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.8.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 8
3.9 Balrog subsystem - Route planning . . . . . . . . . . . . . . . . . . . . . . 8
3.9.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
3.9.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
TSRT10Marcus Back
Invenire [email protected]
LipsPage ii
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.9.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 8
3.10 Balrog subsystem - Control . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.10.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.10.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.10.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 9
3.11 Balrog subsystem - External communication API . . . . . . . . . . . . . . 9
3.11.1 Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.11.2 Tasks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.11.3 Dependencies to other systems . . . . . . . . . . . . . . . . . . . . . 10
TSRT10Marcus Back
Invenire [email protected]
LipsPage iii
Autonomous mine sweeper: BalrogLiTH
2014-09-19
Document history
Version Date Changes Sign Reviewed
0.1 2014-09-12 First draft MB MS
0.2 2014-09-17 Changes from adviser MB MS
0.3 2014-09-18 Changes from adviser MB MS
1.0 2014-09-19 Version 0.3 approved MB MS
TSRT10Marcus Back
Invenire [email protected]
LipsPage iv
Autonomous mine sweeper: BalrogLiTH
2014-09-19
1 Introduction
This document is a system drawing of an autonomous mine sweeper. Each subsystemis briefly explained with respect to components, tasks and dependencies to other subsys-tems. Further information about what the system shall be able to perform and executeis described in the document ”Requirement Specification”. Each subsystem has beendeveloped by previous projects and the purpose of this year’s project is to improve theperformance of the overall system utilising new sensors and more powerful computationalpower.
1.1 Overview of the system
The autonomous mine sweeping system consists of two main subsystems, the base sta-tion and Balrog. Balrog is a tracked vehicle which is divided into smaller subsystems.Each subsystem perform specific tasks and consists of hardware, software or both. For aschematic overview of the system see figure 1.
Position and mapping
Route planning
Control
Base station
Hand controller
Propulsion
Sensors
IMU
Odometers
Laser scanner
Stereo camera
Mine detection
Obstacle detection
GPS
UltrasonicARM processor
Electric motor
GUI
Balrog
Hardware
SoftwareExt
erna
l com
mun
icat
ion
AP
I
Wireless link
Wireless link
Component
Description
Figure 1: Illustration of the system and its subsystems. Dependencies between subsystemsare illustrated by an arrow pointing from the system towards the dependencies of thatsystem.
TSRT10Marcus Back
Invenire [email protected]
LipsPage 1
Autonomous mine sweeper: BalrogLiTH
2014-09-19
1.2 Definition of terms
The following list is terms used in this document
• Balrog - The autonomous tracked vehicle that will carry out the mine sweeping.
• Hand controller - A remote Xbox hand controller used to control the robot manually.
• Mine - A magnet in the search area to be found by Balrog that represents an actualmine.
• Obstacle - Any kind of item (man made or not) that the robot can not travel through.
• Main control unit - The main computer on the robot.
• Operator - A person controlling Balrog via one of the external interfaces (handcontroller or base station).
• Base station - A software running on a computer. The software communicates withBalrog via Wifi. An operator can use the base station to send commands to Balrogor to read out map data.
• IMU - Inertial measurement unit.
• API - Application programming interface
• PWM - Pulse width modulation
• Service area - The area where Balrog is supposed to search for mines.
• GUI - Graphical User Interface.
TSRT10Marcus Back
Invenire [email protected]
LipsPage 2
Autonomous mine sweeper: BalrogLiTH
2014-09-19
2 Subsystem 1 - Base station
2.1 Overview of the subsystem
Figure 2: Base station
The base station is an ordinary personal computer as shownin figure 2. It communicates with Balrog via Wifi and al-lows the user to monitor the progress of the robot as well ascontrolling it by a limited set of commands. Some configu-ration and troubleshooting of Balrog is also available fromthe base station. The mine sweeping and mapping progressis displayed in a GUI at the base station.
2.2 Components
The components defining the base station are as follows:
• An x86 compatible computer
• A wireless network card
• The application used to connect to Balrog
2.3 Tasks
The base station performs the following tasks:
• Displays estimated position of the vehicle as well as previous position data
• Displays detected mines and contours of detected obstacles
• Displays the probability that the area is fully examined
• Receives and interprets control commands from the GUI
• Forwards control commands to Balrog
• Provides a GUI to configure Balrog
• Receives, presents and saves data obtained from Balrog
2.4 Dependencies to other systems
The base station depends on the external communication API system. It displays selecteddata received from the API.
TSRT10Marcus Back
Invenire [email protected]
LipsPage 3
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3 Subsystem 2 - Balrog
3.1 Overview of the subsystem
Balrog is composed of a mobile mine sweeping platform. The platform is mounted witha computer, later referred to as the main control unit, as well as different sensors. Thesensors are used for navigation, mine detection and obstacle detection purposes. Themovement and control of Balrog is performed by the main control unit. Apart from that,the hand controller and/or the base station is providing operating instructions for Balrog.In image 3 last years Balrog is displayed.
Figure 3: Picture of Balrog from last year
Balrog is divided up into the following subsystems:
• Hand controller
• Sensors
• Propulsion
• Positioning and mapping
• Route planning
• Control
• External communication
TSRT10Marcus Back
Invenire [email protected]
LipsPage 4
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.2 Components
Balrog is equipped with the following components:
• Main control unit
• Tracks
• Engines
• Laser scanner
• Stereo camera
• Ultrasonic sensors
• IMU
• Odometers
• Magnetometer
• Wifi communication device
3.3 Tasks
Balrog shall be able to perform the following tasks:
• Estimate its current position
• Autonomously navigate in the service area
• Detect and map the positions of mines
• Map and avoid obstacles in the service area
• Provide the base station with collected data of the service area
• Be controlled manually from the hand controller or the base station
3.4 Dependencies to other systems
Balrog is dependent of the following systems:
• The hand controller
TSRT10Marcus Back
Invenire [email protected]
LipsPage 5
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.5 Balrog subsystem - Hand controller
The system is equipped with a hand controller to facilitate the control of Balrog. Thehand controller communicates wirelessly with Balrog.
3.5.1 Components
• A hand controller
• A wireless communication link
3.5.2 Tasks
The hand controller simplifies controlling Balrog when in manual mode as well as enablingswitching between manual and automatic mode and performing emergency braking. WhenBalrog detects a mine the hand controller will respond by vibrating.
3.5.3 Dependencies to other systems
The hand control is independent of other systems.
3.6 Balrog subsystem - Sensors
In order for the system to execute its tasks, the system is equipped with different sensorsto determine velocity, position and heading. The sensor system can also detect mines andobstacles.
3.6.1 Components
The system consists of the following sensors, for positioning and mapping:
• A laser distance sensor
• A stereo vision camera
• A GPS
• An IMU with an accelerometer, a gyroscope and a magnetometer
• An ultrasonic range finder
• Odometers
3.6.2 Tasks
The main task of the sensor system is to store, handle and provide measurement data ofthe surroundings, to the other subsystems.
TSRT10Marcus Back
Invenire [email protected]
LipsPage 6
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.6.3 Dependencies to other systems
• External communication API
3.7 Balrog subsystem - Propulsion
Balrog is driven by electric motors connected to tracks with control functions enabledthrough the ARM processor.
3.7.1 Components
• Electric motors
• Tracks
• An ARM processor
3.7.2 Tasks
The propulsion system receives commands from the control system. The commands arethen translated into PWM signals to control the motors.
3.7.3 Dependencies to other systems
The propulsion is independent of other systems.
3.8 Balrog subsystem - Positioning and mapping
The positioning and mapping system determines the position of Balrog and constructs amap of the search area in real time.
3.8.1 Components
• Software
• Mine detection algorithm
• Obstacle detection algorithm
TSRT10Marcus Back
Invenire [email protected]
LipsPage 7
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.8.2 Tasks
Several sensors, namely GPS, odometry, laser, IMU (gyroscope and accelerometer) andmagnetometer, contribute to determining the position of Balrog.
The mine detection algorithm detects the mines, represented as magnets, and saves theirpositions and the margin of uncertainty. The obstacle detection algorithm processes sensordata in order to detect obstacles in the search area. With the information from the mineand obstacle detection algorithms this system constructs a map which is used for theroute planning system. The map is based on the search area defined by the operator atthe base station.
3.8.3 Dependencies to other systems
• Sensors
• External communication API
3.9 Balrog subsystem - Route planning
This system is responsible of determining the route Balrog has to visit going from oneposition to another.
3.9.1 Components
• Software
3.9.2 Tasks
Given the map, a position of Balrog and a position we want to visit, the route planningsystem calculates a sequence of waypoints Balrog can follow to get to the ending position.The set of positions is continuously updated by the information given by the mappingand positioning system. The set of positions is then provided to the control system.
3.9.3 Dependencies to other systems
• Positioning and mapping
• External communication API
TSRT10Marcus Back
Invenire [email protected]
LipsPage 8
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.10 Balrog subsystem - Control
The control system is responsible for steering and driving Balrog.
3.10.1 Components
• Software
3.10.2 Tasks
Given the waypoints generated by the route planning system, the control system is re-sponsible for driving Balrog stably along the route using the position estimated by theposition and mapping system. The control system determines the input signals to theelectric motors and sends the signals to the propulsion system.
3.10.3 Dependencies to other systems
• Positioning and mapping
• Route planning
• External communication API
• Propulsion
3.11 Balrog subsystem - External communication API
The external communication API is responsible for all communication between the Balrog,the base station and the hand controller.
3.11.1 Components
• Software
3.11.2 Tasks
The single task for the external communication is to convey information between thedifferent subsystems. This is done in real time and the purpose is to make it possible forthe Balrog, the base station and the hand controller to communicate efficiently.
TSRT10Marcus Back
Invenire [email protected]
LipsPage 9
Autonomous mine sweeper: BalrogLiTH
2014-09-19
3.11.3 Dependencies to other systems
• Hand controller
• Positioning and mapping
• Control
• Route planning
• Sensors
• Basestation
TSRT10Marcus Back
Invenire [email protected]
LipsPage 10