CN109949370A

CN109949370A - A kind of automatic method for IMU- camera combined calibrating

Info

Publication number: CN109949370A
Application number: CN201910196341.3A
Authority: CN
Inventors: 刘军传; 田乃鲁; 翁海峰; 刘克志
Original assignee: Suzhou Tian Zhun Science And Technology Co Ltd
Current assignee: Suzhou Tian Zhun Science And Technology Co Ltd
Priority date: 2019-03-15
Filing date: 2019-03-15
Publication date: 2019-06-28
Anticipated expiration: 2039-03-15
Also published as: CN109949370B

Abstract

The present invention provides a kind of automatic methods for IMU- camera combined calibrating, it provides a kind of IMU- camera combined calibrating method of full-automation for the unmanned equipment including unmanned plane, vehicle, mobile machine, easily can carry out fast joint calibration to IMU- camera in batch production.IMU and camera are mounted in equipment to be calibrated, equipment to be calibrated is fixed on to the output end of six shaft mechanical arms later, the front position of camera is provided with scaling board under original state, drive the output end of six shaft mechanical arms that equipment to be calibrated is driven to be moved according to setting track, scaling board is within the field range of camera in motion process, in motion process, it is acquired by IMU data output frequencies and saves IMU initial data, it is acquired by camera data output frequency simultaneously and saves camera image data, pass through the tool box kalibr later, the IMU initial data and camera image data of preservation are calculated, obtain the transformation matrix of IMU coordinate system and camera coordinates system, and calibrated error.

Description

A kind of automatic method for IMU- camera combined calibrating

Technical field

The present invention relates to the technical field of automatic Pilot, specially a kind of automation side for IMU- camera combined calibrating Method.

Background technique

In the mobile-robot systems such as unmanned plane, automatic driving vehicle, it is often used SLAM (positioning immediately and map structure Build) technology realize robot autonomous localization and navigation.Vision SLAM there are output frequencies low, rotary motion or movement rate add The problems such as positioning easily fails when fast, and IMU has the advantages that output frequency is high, can export 6DOF metrical information；Therefore at this stage A research hotspot be to merge vision SLAM with the pose estimated result that IMU is obtained, obtain more accurately exporting As a result.

When MU and camera are carried out fusion calibration by the prior art, the prior art is for small drone, mobile robot etc. Equipment acquires nominal data by way of people's mobile device；For large scale equipments such as automatic driving vehicles, make equipment edge itself Certain track is moved to obtain nominal data.The former operates by people, and the successful and consistency of calibration are difficult to obtain It ensures；The latter needs driver or operator's remote control equipment to move, and to realize to abundant sharp on IMU six-freedom degree It encourages, has strict requirements to calibration place and motion profile；It is neither suitable for use in batch production on a large scale.

Summary of the invention

In view of the above-mentioned problems, the present invention provides a kind of automatic method for IMU- camera combined calibrating, for packet It includes the unmanned equipment including unmanned plane, vehicle, mobile robot and a kind of IMU- camera joint of full-automation is provided Scaling method easily can carry out fast joint calibration to IMU- camera in batch production.

A kind of automatic method for IMU- camera combined calibrating, it is characterised in that: IMU and camera are mounted on wait mark On locking equipment, equipment to be calibrated is fixed on to the output end of six shaft mechanical arms later, the front position of camera under original state It is provided with scaling board, the output end of six shaft mechanical arms of driving drives equipment to be calibrated to be moved according to setting track, is moved through Scaling board is within the field range of camera in journey, in motion process, acquires by IMU data output frequencies and to save IMU original Data, while camera image data is acquired and saved by camera data output frequency, later by the tool box kalibr, to preservation IMU initial data and camera image data calculated, obtain the transformation matrix of IMU coordinate system and camera coordinates system, and Calibrated error will calculate transformation matrices obtained later, calibrated error is integrated in equipment built-in system to be calibrated.

It is further characterized by:

The movement of the six shaft mechanicals arm includes along X to, the translation of Y-direction, Z-direction and around torsion shaft, pitch axis, side-sway axis Rotation composition, the setting track of the six shaft mechanicals arm includes following two parts:

A respectively along X to, three Y-direction, Z-direction directions, executed since static acceleration-at the uniform velocity-deceleration-stopping act, transporting Scaling board is always in camera fields of view during dynamic；

B rotating around three torsion shaft, pitch axis, side-sway axis axis, executed since static acceleration-at the uniform velocity-deceleration-stopping is dynamic Make, scaling board is always within the scope of camera fields of view during the motion；

Design has plane reference feature on the scaling board；

The plane reference feature is made of chequered with black and white gridiron pattern.

After adopting the above technical scheme, its automation scaling method proposed is calibrated sensor using mechanical arm carrying Acceleration and deceleration motion is realized in combination, and motion process is steady, and impact noise is small, can obtain higher stated accuracy；The automation mark The method of determining can realize the full automatic combine calibration of IMU- camera, and overall process does not need people's participation, and independent of specific place, Operation is succinct convenient, is not affected by human factors, is suitable for mass production applications.

Detailed description of the invention

Fig. 1 is calibration simplified schematic diagram of the invention.

Specific embodiment

A kind of automatic method for IMU- camera combined calibrating, is shown in Fig. 1: IMU and camera are mounted on to be calibrated set On standby 1, equipment 1 to be calibrated is fixed on to the output end of six shaft mechanical arms 2 later, the front of IMU and camera under original state Position is provided with scaling board 3, and the output end of six shaft mechanical arms 2 of driving drives equipment 1 to be calibrated to be moved according to setting track, Scaling board 3 is within the field range of camera in motion process, in motion process, is acquired and is saved by IMU data output frequencies IMU initial data, while camera image data is acquired and saved by camera data output frequency, pass through kalibr tool later Case calculates the IMU initial data and camera image data of preservation, obtains the transformation of IMU coordinate system and camera coordinates system Matrix and calibrated error will calculate transformation matrices obtained later, calibrated error is integrated in built in equipment to be calibrated and is System.

The movement of six shaft mechanical arms 2 includes along X to, the translation of Y-direction, Z-direction and around torsion shaft, pitch axis, side-sway axis Rotation composition, the setting track of six shaft mechanical arms 2 includes following two parts:

Design has plane reference feature 31 on scaling board 3, and plane reference feature 31 is made of chequered with black and white gridiron pattern.

The translator of Chinese of IMU is Inertial Measurement Unit in text, is to measure object triaxial attitude angle (or angular speed) and add The device of speed.

It include intermediate chequered with black and white gridiron pattern in specific embodiment, on scaling board, a is by the output of six shaft mechanical arms Axis individually along X to, three Y-direction, Z-direction directions, executed since static acceleration-at the uniform velocity-deceleration-stopping act, moving Scaling board is always in camera fields of view in the process；B is by the output shaft of six shaft mechanical arms rotating around torsion shaft, pitch axis, side-sway axis Three axis execute acceleration-at the uniform velocity-deceleration-stopping since static and act, and scaling board is always in camera fields of view during the motion Within the scope of；In motion process, IMU initial data is acquired and saved by IMU data output frequencies, while exporting by camera data Frequency collection simultaneously saves camera image data, later by the tool box kalibr, to the IMU initial data and camera image of preservation Data are calculated, and the transformation matrix and calibrated error of IMU coordinate system and camera coordinates system are obtained, and are later obtained calculating Transformation matrices, calibrated error be integrated in equipment built-in system to be calibrated so that the calibration of equipment to be calibrated is completed.

Its automation scaling method proposed is calibrated sensor combinations using mechanical arm carrying and realizes acceleration and deceleration motion, Motion process is steady, and impact noise is small, can obtain higher stated accuracy；The automation scaling method can realize IMU- camera Full automatic combine calibration, overall process does not need people's participation, and independent of specific place, it is succinct convenient to operate, not by people For factor influence, it is suitable for mass production applications.

Specific embodiments of the present invention are described in detail above, but content is only the preferable implementation of the invention Example, should not be considered as limiting the invention the practical range of creation.It is all to become according to equalization made by the invention application range Change and improve etc., it shall still fall within the scope of this patent.

Claims

1. a kind of automatic method for IMU- camera combined calibrating, it is characterised in that: be mounted on IMU and camera to be calibrated In equipment, equipment to be calibrated is fixed on to the output end of six shaft mechanical arms later, the front position of camera is set under original state It is equipped with scaling board, the output end of six shaft mechanical arms of driving drives equipment to be calibrated to be moved according to setting track, motion process Middle scaling board is within the field range of camera, in motion process, acquires by IMU data output frequencies and saves IMU original number According to, while camera image data is acquired and saved by camera data output frequency, later by the tool box kalibr, to preservation IMU initial data and camera image data are calculated, and the transformation matrix of IMU coordinate system and camera coordinates system, Yi Jibiao are obtained Determine error, transformation matrices obtained will be calculated later, calibrated error is integrated in equipment built-in system to be calibrated.

2. a kind of automatic method for IMU- camera combined calibrating as described in claim 1, which is characterized in that described six The movement of shaft mechanical arm includes that the rotation along X to, the translation of Y-direction, Z-direction and around torsion shaft, pitch axis, side-sway axis forms, institute The setting track for stating six shaft mechanical arms includes following two parts:

A respectively along X to, three Y-direction, Z-direction directions, executed since static acceleration-at the uniform velocity-deceleration-stopping act, be moved through Scaling board is always in camera fields of view in journey；

B executes acceleration-at the uniform velocity-deceleration-stopping since static and acts rotating around three torsion shaft, pitch axis, side-sway axis axis, Scaling board is always within the scope of camera fields of view during the motion.

3. a kind of automatic method for IMU- camera combined calibrating as described in claim 1, it is characterised in that: the mark Design has plane reference feature on fixed board.

4. a kind of automatic method for IMU- camera combined calibrating as claimed in claim 3, it is characterised in that: described flat Face calibration feature is made of chequered with black and white gridiron pattern.