3. 3
Outline
Prediction of Vehicle’s Trajectory
Main Problem
Fractal: Correlation Dimension
Machine Learning: Generative Learning Algorithm
Image Processing
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4. Prediction of Vehicle’s Trajectory
Main Problem
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How to determine the direction the green vehicle will go?
5. Prediction of Vehicle’s Trajectory
Fractal: Correlation Dimension
Chaos Theory
– Correlation dimension (denoted by D), one of the fractal
dimension, is sensitive to the non-linear system behaviors and
reflects the tendency of the non-linear system.
Advantages
– 1. Correlation dimension could be used for extracting signal
features out of a complex non-linear system.
– 2. The output of correlation dimension is simple and intuitive.
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11. Prediction of Vehicle’s Trajectory
Machine Learning: Generative Learning Algorithm
Use Bayes rule 𝑝 𝑦 𝑥 =
𝑝 𝑥 𝑦 𝑝(𝑦)
𝑝(𝑥)
to derive the posterior
distribution on y given x. Then calculate arg𝑚𝑎𝑥
𝑦
𝑝(𝑦|𝑥) as
the output which represents the value of y in the case where
𝑝(𝑦|𝑥) can obtain maximum value.
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12. Prediction of Vehicle’s Trajectory
Machine Learning: Generative Learning Algorithm
𝑝 𝑦 𝑥 =
𝑝 𝑥 𝑦 𝑝(𝑦)
𝑝(𝑥)
x is the function of data acquired from smart phones and y
represents the prediction result (-1 represents turning left, 0
represents turning right, 1 represents turning right).
𝑝 𝑥 = 𝑝 𝑥 𝑦 = 0 ∗ 𝑝 𝑦 = 0 + 𝑝 𝑥 𝑦 = 1 ∗ 𝑝 𝑦 = 1 +
𝑝 𝑥 𝑦 = −1 ∗ 𝑝(𝑦 = −1)
𝑝(𝑥|𝑦) is set to satisfy Gaussian Distribution. The parameters
in the 𝑝(𝑥|𝑦) can be calculated through statistical approach
using the training samples.
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13. Prediction of Vehicle’s Trajectory
Machine Learning: Generative Learning Algorithm
Advantages
– It can use less training samples compared to discriminative learning
algorithm.
– The algorithm complexity is low.
Future work
– Find effective way to solve the problem with the robustness of the
Generative Learning Algorithm.
– How to acquire lane localization data.
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Hello everyone, my name is xiejin. I am glad to give you a report about intelligent traffic system in group 2.
Here’s the outline. This time I would introduce what we are doing now and what we are going to do in the future rather than details in our project. So I divide this report into two parts. The first is about prediction of vehicle’s trajectory and the other is about image processing.
In the first part, I will talk about the main problem we faced and then introduce two methods we used to deal with the problem.
Ok, in this picture, if the green vehicle go along with the green line and we know some data during this period, like acceleration, velocity, longitude and attitude , how to determine the direction the green vehicle will go? To deal with this problem, we rise up two methods.
The first is about correlation dimension. The time is limited, so I just give you a brief introduction about that. Ok, correlation dimension is a concept in chaos theory. It is sensitive to the non-linear system behaviors and reflects the tendency of the non-linear system. And it has some merits. it could be used for extracting signal features and its output is simple and intuitive. From above, if we get different correlation dimensions, we can know which directions vehicles will go. Taking the x-acceleration of a vehicle as an example.
The direction of x-acceleration shows here. Firstly, a vehicle goes along with the blue line and then turns left. During this time, we record the x-acceleration and draw the picture. here.
Secondly, the other vehicle goes along the green line and then turns right. We also draw the picture about x-acceleration here.
Comparing these two pictures, they are similar. But their correlation dimensions are different. Results are here. Actually, this test is repeated 10 times and we do a comparison.
In this figure, dimensions of turning left are lager than turning right. Therefore, if vehicles go along with these two ways, we can predict which direction they will go. Nevertheless, in fact, there are a lot of ways that vehicles can go along with to turn left, turn right and go straight.
For example, like these. Vehicles can go along these two ways to turn left and these two ways to go straight. So in the future, we are going to consider other conditions one by one.
The other method to solve the main problem is using machine learning. In generative learning algorithm, we use Bayes rule like this, to derive the posterior distribution on y given x. and then calculate the maximum probability.
X ……; p(x) can be calculated by this formula.
Utilizing the generative learning algorithm, we can predict the maneuver of drivers when they approach the crossroads.
This algorithm has some advantages. It can use ……, and the complexity is low.
Furthermore, in the future, we need to find effective way to ….. And acquire lane localization data.
The other part in our project is about image processing. It was introduced last week, so I just give you a review.
Last week, Wang Qi had completed the image matching and lane detection in the daytime. And in that group meeting, some students mentioned two problems about image compression and lane detection at night. So now, Wang Qi and Bao Yuting are trying to solve these problems.
That is the end of group.2 report, thank you for your listening.