added documentation to the DeviceTimestamp.msg

Author: HannesSommer

cuckoo_time_translator/msg/DeviceTimestamp.msg

@@ -1,7 +1,25 @@
+####
+# This message's purpose is to support the user when tuning device time translation.
+# It collects all the relevant input and output such that a mutual comparison of various configuration (algorithms / parametes) and the current configuration in the driver is possible given a single bag file.
+# It can also be used to inspect the performance of the current configuration.
+####
+
+# The standard header's timestamp should be the device time translated into local / system time, potentially plus an artificial offset (see below)
 Header header
+
+# the device clock stamp of the event in the device (e.g. LIDAR beam fire)
 uint64 event_stamp
+# the device clock stamp of the transmission event (e.g. shortly before the transmission (sending) starts) if available separately. Otherwise equal to event_stamp.
 uint64 transmit_stamp
+
+# the local / system clock time of when the device's message was received.
 time receive_time
+
+# the artifical offeset in seconds that was added to the header's timestamp after translating the hardware time (e.g. to correct an known transport delay (would be negative then))
 float32 offset_secs
+
+# correction_secs := receiveTime - translatedTime in seconds (without the offset above)
 float32 correction_secs
+
+# the algorithm employed to compute the timestamp in the header
 uint8 filter_algorithm