Problem description
If the mobile scanning system detects a problem, it displays a notification, warning, or error. Warnings can be resolved by the operator without stopping the mapping session, while errors cannot be resolved without restarting the mapping session.
Types of warnings
The following shows a list of warning messages displayed during scanning:
Warning Message | Comments |
Battery low Replace the low charged battery as soon as possible. | No hot swapping batteries on NavVis MLX Scanning stops automatically before battery runs empty to save work. Continue scanning but monitor the level of the battery. Stop at a convenient moment and replace or recharge the battery. |
Battery level critical The scanning will be stopped. | You must stop scanning and replace or recharge the battery. The scanning session will be stopped automatically after 1 minute. |
Low on memory Your device is running low on available memory (RAM). Finish mapping as soon as possible. | Reduce the amount of RAM you are using during scanning, reduce the quantity of panoramas you are taking, especially if before you were triggering more than one image every 1.5 seconds for the last minute. Large areas (e.g. outdoors) increases RAM usage. |
Memory critically low Your device is running low on available memory (RAM). Mapping will stop, and your dataset will auto-save in 1 min | There not enough RAM to continue scanning. The scanning session will be stopped automatically after 1 minute. |
The system load is high. Stop moving and wait until the live map responds smoothly. | The CPU of the device is over loaded. This can occur if you are taking panoramas quickly, or in very large out door complex environments, that have multiple moving objects. Slow down and wait for the device to catch up. |
Low on storage Stop the mapping, save the current dataset, and free up space by deleting outdated datasets. |
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Storage critically low Stop mapping and save the dataset as soon as possible | You must stop scanning now and save the dataset immediately. |
Storage is almost full Mapping will stop, and the dataset will autosave in 1 minute. | The scanning session will be stopped automatically after 1 minute. |
You are approaching the maximum recommended mapping time. Finish your dataset in the next 10 minutes. | The optimum scan period for one session is 45 minutes. |
You have reached the maximum time we recommended for mapping. Finish your dataset soon to avoid potential scalability issues during post-processing. | The scanning session will continue, but the scanning session has reached the optimum length in time. |
Mapping accuracy low Please make sure the SLAM status bar stays green. | Check the quality screen on the display is consistently displaying green. Refer to Quality Screen. |
Position lost Tilt the device upright and turn around to recover SLAM. | The device is lost and needs to recover. Refer to How slam affects the accuracy of your scan and how to improve it |
Error while capturing images Please try again. Please contact support if this keeps happening. |
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Types of errors
The following shows a list of error messages displayed during scanning:
Code | Description |
ERR_IMU_RATE_LOW | Message: Something went wrong! The current dataset will be stopped and saved |
Cause: The sensor is not running with the expected rate. A long mapping time might be the cause for this behavior. | |
ERR_IMU_NO_MSGS_YET | Message: Something went wrong! The current dataset will be stopped and saved |
Cause: The sensor has not sent any data yet. This is most likely a hardware problem. | |
ERR_IMU_MSG_TOO_OLD | Message: Something went wrong. The current dataset will be stopped and saved. |
Cause: The sensor stopped sending data. This is most likely a hardware problem, but a long mapping time might be the cause for this behavior. | |
ERR_NODE_NOT_RUNNING | Message: Something went wrong! The current dataset will be stopped and saved. |
Cause: A critical software component is not running. | |
ERR_IMU_VALUES_NAN | Message: Something went wrong! The current dataset will be stopped and saved. |
Cause: The IMU is sending invalid data. This is most likely a hardware problem | |
STATE_ERR_SYSTEM_MEMORY_USAGE_CRITICAL | Message: Memory critically low. Your device is running low on available memory (RAM). Mapping will stop, and your dataset will auto-save in 1 min. Cause: A long mapping time might be the cause of this behavior. |
Shown here is an example of what the screen looks like if there is an error.
FAQ
What happens when the mobile scanning system detects a problem?
It displays a notification, warning, or error.
Can warnings be resolved without stopping the mapping session?
Yes, warnings can be resolved by the operator without stopping the mapping session.
What should I do if I see the warning 'WARN_LASER_HORIZ_INVALID_MEAS'?
You should move the front of the device towards the closest wall that is less than 30 meters away.
What does the error 'ERR_IMU_RATE_LOW' indicate?
It indicates that something went wrong, and the current dataset will be stopped and saved due to the sensor not running at the expected rate.
Is it possible to continue mapping if an error occurs?
No, errors cannot be resolved without restarting the mapping session.
What does the warning 'WARN_SYSTEM_LOAD_HIGH' mean?
It means that the system has high computation usage, and you should slow down or pause the mapping for a while.
What should I do if I encounter the error 'STATE_ERR_SYSTEM_MEMORY_USAGE_CRITICAL'?
You should be aware that your device is running low on available memory (RAM), and mapping will stop, with your dataset auto-saving in 1 minute.
Are there specific causes for the errors displayed during scanning?
Yes, many errors are caused by hardware problems or the sensor not sending data as expected.
What does the warning 'WARN_NODE_LOAD_HIGH' suggest?
It suggests that a software component has high computation usage, and you should slow down or pause the mapping for better results.
Can we use stickers in tunnels to break up the space visually to help the visual odometry supplement lidar SLAM? What are the size and spacing recommendations?
In order to achieve the highest possible accuracy, try to make sure that Lidar SLAM is fully constrained. In environments where this can't be achieved (e.g. tunnels), visual SLAM (VO) will take over to make sure that the map doesn't break. If the cameras can't track enough features in the environment, you can help by adding textured stickers on the wall. The size and spacing depend on the size of the environment but a DIN A4 sized sheet every 2m might be a good rule of thumb.