Source Code for Module mbdyn.bindings.joints

 1  #!/usr/bin/env python 
 2  # -*- coding: utf-8 -*- 
 3  # 
 4  # This file is part of MBDyn sim suite. 
 5  # Copyright (C) 2007 André ESPAZE, as part of a Master thesis supervised by 
 6  # Martin O.L.Hansen (DTU) and Nicolas Chauvat (Logilab) 
 7   
 8  # MBDyn sim suite is free software; you can redistribute it and/or modify 
 9  # it under the terms of the GNU General Public License as published by 
10  # the Free Software Foundation; either version 2 of the License, or 
11  # (at your option) any later version. 
12  # 
13  # This program is distributed in the hope that it will be useful, 
14  # but WITHOUT ANY WARRANTY; without even the implied warranty of 
15  # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
16  # GNU General Public License for more details. 
17  # 
18  # You should have received a copy of the GNU General Public License 
19  # along with this program; if not, write to the Free Software 
20  # Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. 
21  # 
22  """The classes implemented in the joint group. 
23  Currently, the only available class is 
24  L{BindingsHingeJoint<mbdyn.bindings.joints.BindingsHingeJoint>}, 
25  that allows to set an angle value at each time step. 
26   
27  All the classes are contained into L{JOINT_CLASS}, then used 
28  by L{mbdyn.bindings.groups}. 
29  """ 
30  import numpy as N 
31  from mbdyn.bindings.elements import Joint 
32   
33 -class DriveHingeJoint(Joint): 
34      """The interface of the C{DriveHingeJoint} class.  
35      Currently not implemented""" 
36      pass 
37   
38 -class BindingsHingeJoint(DriveHingeJoint): 
39      """A drive hinge joint on which the angle value 
40      can be set at every time step""" 
41   
42 -    def __init__(self, c_inst=None): 
43          DriveHingeJoint.__init__(self, c_inst) 
44          self.value = N.zeros((3, 1)) 
45   
46 -    def get_value(self): 
47          """Return the angle vector 
48           
49          @rtype: a Numpy array 
50          @return: vector of size 3x1""" 
51          return self.value.copy() 
52   
53 -    def set_value(self, array): 
54          """Set the angle vector on the drive hinge joint. 
55   
56          @type array: a Numpy array 
57          @param array: a vector of size 3x1""" 
58          for idx in range(3): 
59              self.value[idx] = array[idx] 
60              self.c_inst.ThetaVec.set_value(idx, float(array[idx])) 
61   
62   
63  JOINT_CLASS = {} 
64   
65  JOINT_CLASS["general"] = Joint 
66  JOINT_CLASS["DriveHingeJoint"] = DriveHingeJoint 
67  JOINT_CLASS["BindingsHingeJoint"] = BindingsHingeJoint 
68