from __future__ import print_function from LogAnalyzer import Test,TestResult import DataflashLog import numpy class TestVibration(Test): '''test for accelerometer vibration (accX/accY/accZ) within recommendations''' def __init__(self): Test.__init__(self) self.name = "Vibration" def run(self, logdata, verbose): self.result = TestResult() if logdata.vehicleType != VehicleType.Copter: self.result.status = TestResult.StatusType.NA return # constants gravity = -9.81 aimRangeWarnXY = 1.5 aimRangeFailXY = 3.0 aimRangeWarnZ = 2.0 # gravity +/- aim range aimRangeFailZ = 5.0 # gravity +/- aim range if not "IMU" in logdata.channels: self.result.status = TestResult.StatusType.UNKNOWN self.result.statusMessage = "No IMU log data" return # find some stable LOITER data to analyze, at least 10 seconds chunks = DataflashLog.DataflashLogHelper.findLoiterChunks(logdata, minLengthSeconds=10, noRCInputs=True) if not chunks: self.result.status = TestResult.StatusType.UNKNOWN self.result.statusMessage = "No stable LOITER log data found" return # for now we'll just use the first (largest) chunk of LOITER data # TODO: ignore the first couple of secs to avoid bad data during transition - or can we check more analytically that we're stable? # TODO: accumulate all LOITER chunks over min size, or just use the largest one? startLine = chunks[0][0] endLine = chunks[0][1] #print("TestVibration using LOITER chunk from lines %s to %s" % (repr(startLine), repr(endLine))) def getStdDevIMU(logdata, channelName, startLine,endLine): loiterData = logdata.channels["IMU"][channelName].getSegment(startLine,endLine) numpyData = numpy.array(loiterData.dictData.values()) return numpy.std(numpyData) # use 2x standard deviations as the metric, so if 95% of samples lie within the aim range we're good stdDevX = abs(2 * getStdDevIMU(logdata,"AccX",startLine,endLine)) stdDevY = abs(2 * getStdDevIMU(logdata,"AccY",startLine,endLine)) stdDevZ = abs(2 * getStdDevIMU(logdata,"AccZ",startLine,endLine)) if (stdDevX > aimRangeFailXY) or (stdDevY > aimRangeFailXY) or (stdDevZ > aimRangeFailZ): self.result.status = TestResult.StatusType.FAIL self.result.statusMessage = "Vibration too high (X:%.2fg, Y:%.2fg, Z:%.2fg)" % (stdDevX,stdDevY,stdDevZ) elif (stdDevX > aimRangeWarnXY) or (stdDevY > aimRangeWarnXY) or (stdDevZ > aimRangeWarnZ): self.result.status = TestResult.StatusType.WARN self.result.statusMessage = "Vibration slightly high (X:%.2fg, Y:%.2fg, Z:%.2fg)" % (stdDevX,stdDevY,stdDevZ) else: self.result.status = TestResult.StatusType.GOOD self.result.statusMessage = "Good vibration values (X:%.2fg, Y:%.2fg, Z:%.2fg)" % (stdDevX,stdDevY,stdDevZ)