ilqgames
A new real-time solver for large-scale differential games.
proximity_cost.h
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34  * Authors: David Fridovich-Keil ( dfk@eecs.berkeley.edu )
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36 
37 ///////////////////////////////////////////////////////////////////////////////
38 //
39 // Penalizes (thresh - relative distance)^2 between two pairs of state
40 // dimensions (representing two positions of vehicles whose states have been
41 // concatenated) whenever relative distance is less than thresh.
42 //
43 ///////////////////////////////////////////////////////////////////////////////
44 
45 #ifndef ILQGAMES_COST_PROXIMITY_COST_H
46 #define ILQGAMES_COST_PROXIMITY_COST_H
47 
48 #include <ilqgames/cost/time_invariant_cost.h>
49 #include <ilqgames/utils/types.h>
50 
51 #include <string>
52 #include <utility>
53 
54 namespace ilqgames {
55 
57  public:
58  ProximityCost(float weight,
59  const std::pair<Dimension, Dimension>& position_idxs1,
60  const std::pair<Dimension, Dimension>& position_idxs2,
61  float threshold, const std::string& name = "")
62  : TimeInvariantCost(weight, name),
63  threshold_(threshold),
64  threshold_sq_(threshold * threshold),
65  xidx1_(position_idxs1.first),
66  yidx1_(position_idxs1.second),
67  xidx2_(position_idxs2.first),
68  yidx2_(position_idxs2.second) {}
69 
70  // Evaluate this cost at the current input.
71  float Evaluate(const VectorXf& input) const;
72 
73  // Quadraticize this cost at the given input, and add to the running
74  // sum of gradients and Hessians.
75  void Quadraticize(const VectorXf& input, MatrixXf* hess,
76  VectorXf* grad) const;
77 
78  private:
79  // Threshold for minimum squared relative distance.
80  const float threshold_, threshold_sq_;
81 
82  // Position indices for two vehicles.
83  const Dimension xidx1_, yidx1_;
84  const Dimension xidx2_, yidx2_;
85 }; //\class ProximityCost
86 
87 } // namespace ilqgames
88 
89 #endif