cb_check.py

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#!/usr/bin/env python
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##\author Kevin Watts
##\brief Prints output of PR2 counterbalance check

PKG = 'pr2_counterbalance_check'
import roslib
roslib.load_manifest(PKG)

import os, sys
import rospy

from pr2_self_test_msgs.srv import *
from std_msgs.msg import Bool
from joint_qualification_controllers.msg import CounterbalanceTestData

from pr2_counterbalance_check.counterbalance_analysis import *

from optparse import OptionParser

def dir(turns):
    return 'CW' if turns > 0 else 'CCW'

SPRING_TOL = 2.0
BAR_TOL = 0.8

def _check_valid(params):
    if params.timeout_hit:
        print >> sys.stderr, "Counterbalance controller timeout hit. Increase teh timeout and retry."
        return False
    
    return True

class CounterbalanceCheck(object):
    def __init__(self, model_file):
        self._motors_halted = True
        self._data = None

        self.motors_topic = rospy.Subscriber('pr2_ethercat/motors_halted', Bool, self._motors_cb)
        self.data_topic = rospy.Subscriber('cb_test_data', CounterbalanceTestData, self._data_callback)

        self._model_file = model_file

        self._ok = True

    @property
    def has_data(self): return self._data is not None

    def _motors_cb(self, msg):
        self._motors_halted = msg.data
        
        if self._motors_halted:
            print >> sys.stderr, "Motors halted. Adjustment data will be invalid."

        self._ok = self._ok and not self._motors_halted

    @property
    def ok(self): return self._ok

    def _data_callback(self, msg):
        self._data = msg
        
    def process_results(self):
        data = CounterbalanceAnalysisData(self._data)
        params = CounterbalanceAnalysisParams(self._data)

        if not _check_valid(params):
            print >> sys.stderr, "Unable to calculate adjustment, invalid data"
            return

        (secondary, cb_bar) = calc_cb_adjust(data, self._model_file)

        if (abs(secondary) > 25 or abs(cb_bar) > 25):
            print >> sys.stderr, "Unable to calculate CB adjustment. This could mean the counterbalance is extremely out of adjustment, or your training data is invalid."
            return

        print 'Calculated counterbalance adjustment recommendations:'
        print '\tSecondary Spring: %.1f (%s)' % (abs(secondary), dir(secondary))
        print '\tArm Gimbal Shaft: %.1f (%s)' % (abs(cb_bar), dir(cb_bar))
        print 'Make sure to follow proper adjustment procedures if you choose to make an adjustment.\n'
        print 'Your counterbalance state is up to you, these adjustments are only recommendations.\n'

            
if __name__ == '__main__':
    parser = OptionParser("./cb_check.py model_file")
    parser.add_option("-t", "--tol", action="store_true",
                      dest="tolerance", default=False,
                      help="Print recommended tolerances and exit")
    
    options, args = parser.parse_args(rospy.myargv())
    
    if options.tolerance:
        print 'Recommended CB tolerances for secondary spring, arm gimbal shaft'
        print '\tSecondary spring: +/-%.1f' % SPRING_TOL
        print '\tArm Gimbal Shaft: +/-%.1f' % BAR_TOL
        print 'If your recommended adjustment is less than this many turns, do not adjust your CB'
        sys.exit()

    if len(args) < 2:
        parser.error("No model file specified. Please give training data file to calculate adjustment")
        sys.exit(2)

    if not os.path.exists(args[1]):
        parser.error("Model file does not exist. Please give training data file to calculate adjustment")
        sys.exit(2)

    rospy.init_node('cb_analysis')
    app = CounterbalanceCheck(args[1])
    try:
        my_rate = rospy.Rate(5)
        while app.ok and not app.has_data and not rospy.is_shutdown():
            my_rate.sleep()

        if not app.ok:
            print >> sys.stderr, "Unable to calculate adjustment. Check motors halted. Please retry."
            sys.exit(2)

        if not rospy.is_shutdown():
            app.process_results()
    except KeyboardInterrupt, e:
        pass
    except Exception, e:
        print 'Caught Exception in CB application check'
        import traceback
        traceback.print_exc()