---
title: "NavVis post-processing fails with 'check failed: rotation_vectornorm()"
slug: "post-processing-fails-with-check-failed-rotation-vectornorm"
tags: ["Error message", "NavVis IVION Processing", "Failed Processing", "SLAM Error", "Cloud Processing Error", "Troubleshooting Processing"]
updated: 2024-03-18T15:17:11Z
published: 2024-03-18T15:17:11Z
canonical: "knowledge.navvis.com/post-processing-fails-with-check-failed-rotation-vectornorm"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://knowledge.navvis.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Post-processing fails with 'Check failed: rotation_vectornorm()'

## Introduction

### Problem description

Post-processing fails with:

```plaintext
[ERROR] Check failed: rotation_vector.norm() < 3.14159265358979323846 / 2. (2.34959 vs. 1.5708) Sigma point is far from the mean, recovered delta may be incorrect.
[31mERROR: Could not process dataset '/tmp/inputs/2020-09-17_20.28.09': Command 'rosrun surveyor_ros surveyorslam_processing_node --configuration_directory=/opt/NavVis/slam/share/surveyor_ros/'configuration_files' --configuration_directory=/opt/NavVis/mapper/share/navvis_mapper/launch/Y2 --configuration_basename=slam_config_offline.lua --velodyne_calibration=/opt/NavVis/ros-shared/share/velodyne_pointcloud/params/VLP16db.yaml --clock --assets-output-dir=/tmp/outputs/datasets_proc/2020-09-17_20.28.09_1 --anchor-frame=anchor_cross --sensor-frame=/tmp/inputs/2020-09-17_20.28.09/sensor_frame.xml --dynamic-frames-tf-topics=head_body --bags /tmp/navvis_postproc_dataset_2020-09-17_20.28.09@2020-09-28_17.01.06/rewritten/bag_sensor_data_3.bag /tmp/navvis_postproc_dataset_2020-09-17_20.28.09@2020-09-28_17.01.06/rewritten/bag_sensor_data_1.bag /tmp/navvis_postproc_dataset_2020-09-17_20.28.09@2020-09-28_17.01.06/rewritten/bag_sensor_data_2.bag /tmp/navvis_postproc_dataset_2020-09-17_20.28.09@2020-09-28_17.01.06/rewritten/bag_sensor_data_0.bag /tmp/outputs/datasets_proc/2020-09-17_20.28.09_1/artifacts/height_adjust.bag --device-certificate=/etc/NavVis/workstation.cer --publish-tf-tree --no-roscore --imu-topic /imu/imu_raw/data --laser-scan-topics /
```

**Root cause**

SLAM diverges in the internal Kalman filter.

### Scope

This solution applies to the post-processing software and NavVis IVION Processing.

## Troubleshooting procedure

1. As the SLAM and the Kalman filer are probabilistic, first try re-processing.
2. If that doesn't help, the Dataset needs to be cut with `nv_cut-dataset` at the position where the SLAM breaks ([nv_cut-dataset documentation](/v1/docs/nv-cut-dataset)).

Simultaneous Localization And Mapping

Functionality that allows processing of data recorded by NavVis devices. Processing recorded datasets is necessary to be able to use the data in an application like NavVis IVION.

A dataset is a piece of a site, the result of a continuous recording with a NavVis mapping device or the result of an imported point cloud. Datasets can contain panoramic images and point clouds.