Autonomous Weeder for Christmas Trees – Basic Development and Tests

Figure A2 Body of iterating subsystem

Figure A2 Body of iterating subsystem with the following blocks:

  • The For Iterator outputs a value (1, 2, 3, ... updated for each iteration of the subsystem)
  • The StepGenerator converts the iteration count to a pulse length to simulate
  • The ParamCEEX_Predictor simulates the state of the vehicle look_ahead_time in the future. The outputs are:
    • The simulated position (relative to reference)
    • The simulated heading (relative to reference)
    • The steering actuator feedback (i.e. the simulated steering angle).
  • The inputs are:
    • The (perceived) position (relative to reference).
    • The heading (relative to reference)
    • The steering actuator feedback (i.e. the current steering angle)
    • The vehicle speed
    • The expected change in steering actuator position (feedback value) and when this change occurs
    • Configuration constants (how far ahead in the future should the simulation go, what is the distance from the rear wheel center to the antenna (along x axis)).
  • The Error Function block then calculates the error value corresponding to the simulated vehicle state.
  • The HoldMinimum block then remembers which control pulse gave the least simulated error. This is the output from this subsystem!

 



Version 1.0 November 2005, © Danish Environmental Protection Agency