Understanding Position Updates
Interpret the information presented in a position update from the device log of the ZeroKey Config Tool and Gateway Console, as well as Tera Term.
What is a Device Log Position Update?
A position update is a string of information printed in the Device Log of the Config Tool. It contains all the information sent to the Gateway by a given Mobile and other system information that is used to report the position of that Mobile at the time indicated.
The following is an example of a position update in the Device Log:
[2024-04-22T13:15:09.8023] |I| rf_cmd_update_position: Node: FB:37:5A:4D:2E:FD seq: 839 ins: 0 pos: 1.59043,0.38237,-0.00392 vel: -0.00005,0.00014,-0.00001 rot: 0.99999,0.00040,-0.00143,-0.00470 flag: 00 pf: 33 ts: 90942976
Position Update Review and Breakdown
Real-world Timestamp
[2024-04-22T13:15:09.8023]
This segment indicates the exact date and time of the user’s system when the positioning update was produced.
System Message Type. E = Error, I = Info, V = Verbose, D = Debug
|I|
This segment indicates the message level for system debugging purposes. After connection, the Config Tool configures the system to output Debug level, which is the highest message level. Please note that Debug level is not configurable by the user.
Update Type
rf_cmd_update_position:
This segment acts as the header for indicating the update message type.
MAC Address of the Mobile
Node: FB:37:5A:4D:2E:FD
This segment represents the unique device identifier generated during the Mobile’s manufacturing. It consists of 6 bytes in hexadecimal representation, and 12 characters total.
Ultrasonic Position Sequence Number
seq: 839
This segment indicates the sequence number of this ultrasonic positioning epoch on the given Mobile. Sequence numbers increment after each ultrasonic positioning calculation, allowing the sequence to be used to identify duplicate or missing messages.
INS Position Sequence Number
ins: 0
This segment indicates the INS sequence number, and is an identifier for each INS Position generated based on the current ultrasonic epoch.
X, Y, Z Position
pos: 1.59043, 0.38237, -0.00392
This segment indicates the X, Y, and Z positions of the Mobile at the given time, in meters.
Mobile Velocity
vel: -0.00005, 0.00014, -0.00001
This segment indicates the velocity of the Mobile in X, Y, and Z in meters per second.
Orientation
rot: 0.99999, 0.00040, -0.00143, -0.00470
This segment indicates the orientation of the Mobile, expressed as a unit quaternion: a + bi + cj + dk
Flag
flag: 00
This segment specifies the status of the power button, if present:
“00” indicates that the button is not being pressed.
“01” indicates that the button is being pressed.
Position Flag
pf: 33
The first digit indicates the IMU fusion positioning quality (0-6). The second digit indicates the ultrasonic positioning quality (0-3).
For more information on positioning flags, visit our help article Understanding Positioning Flags for Third-Party Integration.
System Time Sync
ts: 90942976
This segment indicates the timestamp of the position update relative to the Gateway’s uptime, in microseconds.