Uncertainty
Uncertainty
Uncertainty
Uncertainty
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Probability
✓ Probability that a random variable X has value x
✓ Example:
✓ Abbreviation:
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Probability
✓ Probability density function
❖ Univariate normal distribution
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Probability
✓ Probability density function mean vector covariance matrix
❖ Multivariate normal distributions
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Probability
✓ Probability density function
❖ Probability of the random variable falling within a particular range of
values
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Probability
✓ Joint distribution of 2 random variables
✓ Conditional probability
✓ Bayes rule
✓ Conditional independence
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Localization Problem
✓ Indoor
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Localization Problem
✓ Outdoor
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Why localization problem?
✓ Fundamental problem in robotics
✓ Control noise
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Localization Problem
✓ 1D localization ✓ 2D localization
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Robot & Environment
✓ State
✓ Control actions
✓ Sensor measurements
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Robot & Environment
✓ State evolution: state transition probability
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Robot & Environment
✓ Measurement model:
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Robot & Environment
✓ Measurement model:
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Robot & Environment
✓ Hidden Markov chain:
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Belief
✓ Belief
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Bayesian filter
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Bayes filter
✓ Example
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Bayes filter
✓ Example
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Bayes filter
✓ No closed form solution in general
✓ Two approachs:
❖ Gaussian filters
❖ Nonparametric filters
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Particle filter
✓ Represent the posterior bel(xt) by a set of random state samples
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Particle filter
✓ Approximate the belief bel(Xt) by the set of particles Xt
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Particle filter
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Particle filter
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Particle filter
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Probability
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Probability
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