This document discusses using an inertial navigation system (INS) for autonomous mobile robot position estimation. It describes some problems with traditional INS, including inability to directly measure speed and yaw. The document then introduces a solution using a dodecahedron-shaped device containing IMU modules on each facet. This design can directly measure speed and yaw through gyroscopic torque measurements and advanced compassing. It is also less dependent on temperature. The document provides details on the hardware design and complexity of the dodecahedron INS.

1. Mahdi Jadaliha

2. Introduction
 To estimate position has always been a
challenge for the mankind, be it navigating
spaceships using Inertial Navigation Systems
(INSs), or simply crossing the desert using
compass or stars to find his direction.
 Different applications call for different
methods, however, the main goal is the same
in all navigation: to estimate or measure
position or some of its derivatives.

3. Problem Definition
 I have been several years in a robotic team. My duty was
finding position of robots and obstacles.
 since an INS refers to no real-world item beyond itself. It is
therefore self-contained, immune to jamming and
deception, non-radiating, and a good candidate for position
estimation in Autonomous Mobile Robots.

4. Problems with INS
 Can’t measure speed directly
 Can’t measure yaw directly
 It is very dependant to temperature
* please refer to
http://en.wikipedia.org/wiki/Inertial_na
vigation_system for more information.

5. Solved with Dodecahedron
 Can measure speed directly
Dodecahedron calculates speed by measuring gyroscopic
torque on different facets.
 Can measure yaw directly
advanced compassing mechanism is developed to estimate
the position of magnetic source(by scattered
measurements on the surface of dodecahedron) , therefore
we can find magnetic field of earth even in a complicated
environment.
 It is not very dependant to temperature
measuring quantities with two sensors in opposite direction
reduces the effect of temperature on their biases
effectively.

7. I have DONE every steps of this
project by myself
 Designing Micro controller and analog circuits
by Altium (Protel)
 Designing PCB board by Altium (Protel)
 Soldering
 Programming Microcontroller by C (MPLAB)
 Programming data accusation software on PC
by Delphi

12. I tried 3 times to make best
measurements

13. Main component of IMU modules
Each modules is a
complete Inertial
Measurement Unit
(IMU). It has 3
perpendicular
axes of
measurement for
Accelerometers
and Gyroscopes.
Each module
(pentagonal) has
capabilities equal
to Xsense
commercial
Products.
(http://www.xsen
s.com/)

14.  However I designed this
Dodecahedron for Autonomous
vehicle, the modules can be used
in different configuration for
different propose.
 Motion Tracking is one of the most
popular use of these modules.
Motion tracker
* please refer to very exciting Video
http://www.moven.com/Static/Docume
nts/UserUpload/Moven_movie/product_
reel2009.wmv for more information. From: www.xsense.com

15. Dodecahedron Hardware complexity
 It is made from 770 discreet electrical component
 Measures 108 Sensory Quantity
 It uses Distributed Processing with 12 DSP
 Support RS485, RS232, SPI, CAN to communicate
 Advanced Data Structure to reduce communication
faults
 Manage all process by Interrupts in an event trigger
manner to reduce power consumption
 Uses DMA to decrease process load

17. Geometrical shape
 Appendix: Platonic Solids
Name V F E F-Type Truncation Dual
tetrahedron 4 4 6 triangles truncated tetrahedron tetrahedron
cube 8 6 12 squares truncated cube octahedron
octahedron 6 8 12 triangles truncated octahedron cube
dodecahedron 20 12 30 pentagons truncated dodecahedron icosahedron
icosahedron 12 20 30 triangles truncated icosahedron odecahedron
tetrahedron cube octahedron dodecahedron icosahedron
All vertices, edge mid-points and face mid-points lie on concentric spheres
All faces are the same shape and are all regular polygons
Thus all edges are equal in length and face corners equal in angle.
Duals are also all Plationic Solids.
The cube is also called a hexahedron
[1] http://www.cit.gu.edu.au/~anthony/graphics/polyhedra/