Ind wks first week

Inspired by other projects in charge , Think Dubins The curve is feasible in the player's specific path planning .

1、Dubins Curve overview

Dubins The curve is in the case of accessibility , Provide an optimal forward path , And A* ,RRT Compare with those search algorithms , Another advantage is that the planned path meets the kinematic requirements .

（ The picture below is taken from the Internet ） yes Dubins Six basic forms of curves , The first four are most commonly used , In a word, a generalization is a vector with a known starting point （ Coordinates and directions ） And the vector of the target point , With the help of dubins Curve algorithm can solve the shortest path .

2、 Why do you think of transplantation Dubins curve ？

（1）Dubins Curves were first used in vehicle motion planning , It is also widely used in the field of unmanned aerial vehicles , According to my current basic understanding of simulation players , These are similar , Include ： The forward direction is generally forward and the U-turn action is complex 、 There is a limit to the maximum turning curvature when turning 、 The motion state of a point at a certain time can be abstracted as a vector .

（2）Dubins The curve is significantly better than the common A* Equal basic algorithm , And it is basically derived by mathematical calculus , Low dependence on search , Furthermore, the algorithm complexity is low .

（3）robocup The player's penalty mechanism is to decide the penalty according to the number of collisions when there is a collision , Therefore, if we can minimize the collision that does not happen because of grabbing the ball , You can reduce the number of times you are sent off .

（4） Watch the code of other teams and find , There are often automatic falls during walking , Part of the situation is related to the excessive turning angle , If you use this curve , Then the maximum curvature can be given by the student who designed the action after the experiment , Can reduce the situation of self falling .

（5） This curve itself is relatively simple , The basic type is “ arc —— A straight line —— arc ”, It does not involve actions such as reversing and turning around in place, which have a large loss of speed , And then make the displacement as large as possible in a short time .

3、 Thinking about whether transplantation is meaningful

（1） By observing the team code game , At present, it is difficult to see a similar curve trajectory in the team path .

（2） As the ball moves , The target position and direction of players change very fast , And this curve track changes greatly when the target point , It may be difficult to cross to a straight line when traveling all the way along the arc segment .

（3） in the light of （2）, Have you thought about it onball Applied ideas , I also thought of the idea of experimenting in the allocation of players far from the ball .

4、 Difficulties encountered

（1） Not familiar with the team code , Failed to call existing functions skillfully , Often look for code for a long time .

（2） Concerns about effectiveness , If it takes more time to complete the experiment, but the effect is not good , It may slow down the progress of the whole team .