Company LOGO Mid semester presentation Spring 2008/9 Performed by: Alexander PavlovDavid Domb Supervisor: Mony Orbach GPS/INS Computing System

Agenda 1. General overview 2. Our Project 4. What’s Next… GPS/INS Computing System 3. The Design

GPS/INS Computing System General overview “Even Noah got no salary for the first six months partly on account of the weather and partly because he was learning navigation.” Mark Twain

Theoretical Navigation Algorithm 0 Initialization 1 Particle Propagation 2 Particle Update & Normalization 3 State Estimation 4 Effective N calculation 5 D computation 6 Re-sampling 7 Regularization 8 Weight Re-computation GPS/INS Computing System  Developed in the “Technion” and Implements the tightly coupled INS/GPS navigation unit, with the particle filter.  The algorithm stages:

Project Goals Establishing the efficiency of the particle filter based, tightly coupled INS/GPS navigation unit realization. Designing an efficient real- time particle filter based, tightly coupled INS/GPS navigation unit. GPS/INS Computing System

GPS Computing System

General Project will be performed in 2 stages. First part in this semester. Project will be performed by several work groups Our group will implement Particle Propagation and State Estimation stages in this first part. Both stages need to be performed whit in 0.01 sec, regardless of other stages performance. GPS Computing System

Group Project Goals – Part 1 Learning GPS/INS navigation using Particle Filter algorithm Learning VHDL language Learning FPGA environment Implementation of Particle Propagation and State Estimation stages of algorithm GPS/INS Computing System

Design guidelines Constrains:  large amount of calculations  Limited hardware  real-time results Selected solution:  Combining Parallel processing whit Pipelines. GPS/INS Computing System

X data structure True State Output Record FieldSign bitNumber bitsFraction bits Position dummy Speed Quaternion Acceleration offset Dreidel offset GPS Receiver offset Dummy 0240 GPS Computing System

INS data structure True State Output Record FieldSign bitNumber bitsFraction bits Acceleration Angular rates GPS Computing System W data structure True State Output Record FieldSign bitNumber bitsFraction bits Weight 0024 Dummy

Solution – Top design GPS/INS Computing System Weight vector Particles propagation unit State estimation unit Estimated State Vector [1..18] Estimated State Vector [1..18] xN Extended State Vector [1..18] Extended State Vector [1..18] Extended State Vector [1..18] Controller

Controller Algorithm GPS/INS Computing System  While “FIFO” is NOT empty: Every 5 clock cycles, send a new particle from the “FIFO”, into the “TOP_6_PROP” (asserting the “START” signal to ‘1’).  Keep count of “START” signals given.  Keep count of “FINISH” signals from the “TOP_6_PROP”.  For every “FINISH” signal, send the matching weight vector and new propagated particle to the “TOP_ESTIMATION”.

Solution – Top design GPS/INS Computing System Weight vector Particles propagation unit State estimation unit Estimated State Vector [1..18] Estimated State Vector [1..18] xN Extended State Vector [1..18] Extended State Vector [1..18] Extended State Vector [1..18] Controller

Particle propagation unit GPS/INS Computing System clock reset start finish

Particle propagation unit GPS/INS Computing System

Propagation timing control GPS/INS Computing System  Every “START” = ‘1’ : counter = counter +1  Propagation unit i starts when: “START” = ‘1’ AND counter mod 6 = i.  “FINISH” = ‘1’ when: “finish_i” = ‘1’ for all i.

Particle propagation unit GPS/INS Computing System

Single particle propagation data flow Format inputs to 48 bits Calculate trigonometric functions Latitude sin/cos Format trigonometric function output to 48 bits R_E, R_e, R_N calculation Denominator calculation d_longitude denominator d_latitude denominator Dividers d_longitude d_lattitude R_e Particle Propagation GPS Computing System

Propagation flow control GPS Computing System

Solution – Top design GPS/INS Computing System Weight vector Particles propagation unit State estimation unit Estimated State Vector [1..18] Estimated State Vector [1..18] xN Extended State Vector [1..18] Extended State Vector [1..18] Extended State Vector [1..18] Controller

Estimation unit GPS/INS Computing System clock reset New Data In Estimation Ready

Estimation unit GPS/INS Computing System W X

Timing Analysis GPS/INS Computing System  1 particle LATENCY – 50 clock cycles (from “start” to “finish”) of propagation and weighting (according to simulation).  Propagation stage LATENCY – 45 clocks.  Estimation stage LATENCY – 5 clocks.  With a pipeline (Throughput) of 5 clocks, and 6 parallel propagation units : 30,000 particles in 105,050 clocks = = Mhz.

COMMENTS GPS/INS Computing System  NO sin/cos blocks: the design uses a “DUMMY” block with a latency of 30 clocks and no throughput.  The estimation of the quaternion matrix is left to be resolved by another grope (by software). The matrix is part of the design’s output.

MID-Results GPS/INS Computing System According to the initial timing analysis, we will probably be able to meet the timing demands - “with time to spare”.

GPS/INS Computing System What’s Next…

Things to do GPS/INS Computing System  Synthesis.  Simulations and testing on the board.  Final report.

GPS/INS Computing System GANTT