speed_limiter.cpp
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00034 
00035 /*
00036  * Author: Enrique Fernández
00037  */
00038 
00039 #include <algorithm>
00040 
00041 #include <diff_drive_controller/speed_limiter.h>
00042 
00043 template<typename T>
00044 T clamp(T x, T min, T max)
00045 {
00046   return std::min(std::max(min, x), max);
00047 }
00048 
00049 namespace diff_drive_controller
00050 {
00051 
00052   SpeedLimiter::SpeedLimiter(
00053     bool has_velocity_limits,
00054     bool has_acceleration_limits,
00055     bool has_jerk_limits,
00056     double min_velocity,
00057     double max_velocity,
00058     double min_acceleration,
00059     double max_acceleration,
00060     double min_jerk,
00061     double max_jerk
00062   )
00063   : has_velocity_limits(has_velocity_limits)
00064   , has_acceleration_limits(has_acceleration_limits)
00065   , has_jerk_limits(has_jerk_limits)
00066   , min_velocity(min_velocity)
00067   , max_velocity(max_velocity)
00068   , min_acceleration(min_acceleration)
00069   , max_acceleration(max_acceleration)
00070   , min_jerk(min_jerk)
00071   , max_jerk(max_jerk)
00072   {
00073   }
00074 
00075   double SpeedLimiter::limit(double& v, double v0, double v1, double dt)
00076   {
00077     const double tmp = v;
00078 
00079     limit_jerk(v, v0, v1, dt);
00080     limit_acceleration(v, v0, dt);
00081     limit_velocity(v);
00082 
00083     return tmp != 0.0 ? v / tmp : 1.0;
00084   }
00085 
00086   double SpeedLimiter::limit_velocity(double& v)
00087   {
00088     const double tmp = v;
00089 
00090     if (has_velocity_limits)
00091     {
00092       v = clamp(v, min_velocity, max_velocity);
00093     }
00094 
00095     return tmp != 0.0 ? v / tmp : 1.0;
00096   }
00097 
00098   double SpeedLimiter::limit_acceleration(double& v, double v0, double dt)
00099   {
00100     const double tmp = v;
00101 
00102     if (has_acceleration_limits)
00103     {
00104       const double dv_min = min_acceleration * dt;
00105       const double dv_max = max_acceleration * dt;
00106 
00107       const double dv = clamp(v - v0, dv_min, dv_max);
00108 
00109       v = v0 + dv;
00110     }
00111 
00112     return tmp != 0.0 ? v / tmp : 1.0;
00113   }
00114 
00115   double SpeedLimiter::limit_jerk(double& v, double v0, double v1, double dt)
00116   {
00117     const double tmp = v;
00118 
00119     if (has_jerk_limits)
00120     {
00121       const double dv  = v  - v0;
00122       const double dv0 = v0 - v1;
00123 
00124       const double dt2 = 2. * dt * dt;
00125 
00126       const double da_min = min_jerk * dt2;
00127       const double da_max = max_jerk * dt2;
00128 
00129       const double da = clamp(dv - dv0, da_min, da_max);
00130 
00131       v = v0 + dv0 + da;
00132     }
00133 
00134     return tmp != 0.0 ? v / tmp : 1.0;
00135   }
00136 
00137 } // namespace diff_drive_controller


diff_drive_controller
Author(s): Bence Magyar
autogenerated on Sat Aug 13 2016 04:20:35