Ejemplo n.º 1
0
    def __init__(self, bfs, gain, trajectory, tau, 
                 add_to_goals=None, **kwargs): 
        """
        bfs int: the number of basis functions per DMP
        gain float: the PD gain while following a DMP trajectory
        trajectory np.array: the time series of points to follow
                             [DOFs, time], with a column of None
                             wherever the pen should be lifted
        tau float: the time scaling term
        add_to_goals np.array: floats to add to the DMP goals
                               used to scale the DMPs spatially
        """

        Control_OSC.__init__(self, **kwargs)

        self.bfs = bfs
        self.gain = gain
        self.gen_dmps(trajectory)
        self.tau = tau
        self.target,_,_ = self.dmps.step(tau=self.tau)

        if add_to_goals is not None: 
            for ii, dmp in enumerate(self.dmp_sets):
                dmp.goal[0] += add_to_goals[ii*2]
                dmp.goal[1] += add_to_goals[ii*2+1]

        self.num_seq = 0

        self.done = False
        self.not_at_start = True
Ejemplo n.º 2
0
    def __init__(self, dt, gain, trajectory, **kwargs):

        Control_OSC.__init__(self, **kwargs)

        self.dt = dt
        self.gain = gain
        self.gen_trajectories(trajectory)
        self.target = np.array([self.y_des[0](0.0), self.y_des[1](0.0)])

        self.num_seq = 0
        self.time = 0.0

        self.done = False
        self.not_at_start = True
Ejemplo n.º 3
0
    def __init__(self, dt, gain, trajectory, **kwargs): 

        Control_OSC.__init__(self, **kwargs)

        self.dt = dt
        self.gain = gain
        self.gen_trajectories(trajectory)
        self.target = np.array([self.y_des[0](0.0), self.y_des[1](0.0)])

        self.num_seq = 0
        self.time = 0.0

        self.done = False
        self.not_at_start = True
Ejemplo n.º 4
0
    def control(self, arm):
        """Drive the end-effector through a series 
           of (x,y) points"""

        if np.sum(abs(arm.x - self.target)) < .01:
            self.not_at_start = False

        if self.not_at_start or self.done:
            u = Control_OSC.control(self, arm)

        else:
            y = np.array([self.y_des[d](self.time) for d in range(2)])
            self.time += self.dt

            # check to see if it's pen up time
            if self.time >= 1:
                self.pen_down = False
                self.time = 0.0
                if self.num_seq >= len(self.seqs_x) - 1:
                    # if we're finished the last sequence
                    self.done = True
                    self.target = [.3, 0]
                else:
                    # else move on to the next sequence
                    self.not_at_start = True
                    self.num_seq += 1
                    self.y_des = [
                        self.seqs_x[self.num_seq], self.seqs_y[self.num_seq]
                    ]
                    self.target = [self.y_des[0](0.0), self.y_des[1](0.0)]
            else:
                self.pen_down = True

            self.x = arm.position(ee_only=True)
            x_des = self.gain * (y - self.x)
            u = Control_OSC.control(self, arm, x_des=x_des)

        return u
Ejemplo n.º 5
0
    def control(self, arm): 
        """Apply a given control signal in (x,y) 
           space to the arm"""

        if np.sum(abs(arm.x - self.target)) < .01:
            self.not_at_start = False

        if self.not_at_start or self.done:
            u = Control_OSC.control(self, arm)

        else:
            y,_,_ = self.dmps.step(tau=self.tau, state_fb=self.x)

            # check to see if it's pen up time
            if self.dmps.cs.x < \
                np.exp(-self.dmps.cs.ax * self.dmps.cs.run_time):

                    self.pen_down = False
                    
                    if self.num_seq >= len(self.dmp_sets) - 1:
                        # if we're finished the last DMP
                        self.done = True
                        self.target = [.3, 0]
                    else:
                        # else move on to the next DMP
                        self.not_at_start = True
                        self.num_seq += 1
                        self.dmps = self.dmp_sets[self.num_seq]
                        self.target,_,_ = self.dmps.step(tau=self.tau)
            else:
                self.pen_down = True

            self.x = arm.position(ee_only=True)
            x_des = self.gain * (y - self.x)
            u = Control_OSC.control(self, arm, x_des=x_des) 

        return u
Ejemplo n.º 6
0
    def control(self, arm):
        """Drive the end-effector through a series 
           of (x,y) points"""

        if np.sum(abs(arm.x - self.target)) < .01:
            self.not_at_start = False

        if self.not_at_start or self.done:
            u = Control_OSC.control(self, arm)

        else: 
            y = np.array([self.y_des[d](self.time) for d in range(2)])
            self.time += self.dt

            # check to see if it's pen up time
            if self.time >= 1: 
                self.pen_down = False
                self.time = 0.0
                if self.num_seq >= len(self.seqs_x) - 1:
                    # if we're finished the last sequence
                    self.done = True
                    self.target = [.3, 0]
                else: 
                    # else move on to the next sequence
                    self.not_at_start = True
                    self.num_seq += 1
                    self.y_des = [self.seqs_x[self.num_seq], 
                                  self.seqs_y[self.num_seq]]
                    self.target = [self.y_des[0](0.0), self.y_des[1](0.0)]
            else: 
                self.pen_down = True
            
            self.x = arm.position(ee_only=True)
            x_des = self.gain * (y - self.x)
            u = Control_OSC.control(self, arm, x_des=x_des)

        return u