Init

rotorpy/trajectories/traj_template.py

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+"""
+Imports
+"""
+import numpy as np
+
+class TrajTemplate(object):
+    """
+    The trajectory is implemented as a class. There are two required methods for each trajectory class: __init__() and update().
+    The __init__() is required for instantiating the class with appropriate parameterizations. For example, if you are doing 
+    a circular trajectory you might want to specify the radius of the circle. 
+    The update() method is called at each iteration of the simulator. The only input to update is time t. The output of update()
+    should be the desired flat outputs in a dictionary, as specified below. 
+    """
+    def __init__(self):
+        """
+        This is the constructor for the Trajectory object. A fresh trajectory
+        object will be constructed before each mission.
+        """
+
+    def update(self, t):
+        """
+        Given the present time, return the desired flat output and derivatives.
+
+        Inputs
+            t, time, s
+        Outputs
+            flat_output, a dict describing the present desired flat outputs with keys
+                x,        position, m
+                x_dot,    velocity, m/s
+                x_ddot,   acceleration, m/s**2
+                x_dddot,  jerk, m/s**3
+                x_ddddot, snap, m/s**4
+                yaw,      yaw angle, rad
+                yaw_dot,  yaw rate, rad/s
+        """
+        x    = np.zeros((3,))
+        x_dot = np.zeros((3,))
+        x_ddot = np.zeros((3,))
+        x_dddot = np.zeros((3,))
+        x_ddddot = np.zeros((3,))
+        yaw    = 0
+        yaw_dot = 0
+
+        flat_output = { 'x':x, 'x_dot':x_dot, 'x_ddot':x_ddot, 'x_dddot':x_dddot, 'x_ddddot':x_ddddot,
+                        'yaw':yaw, 'yaw_dot':yaw_dot}
+        return flat_output