Design And Research Of Pose Adjustment Platform For Laser TV

Laser TV is a new display technology with huge market potential.In order to get a better video viewing experience,laser TV is usually used together with anti-light screen,and placed under the screen.However,it is found deviate from the normal projection and screen relationship easily due to touch in daily life.The current mainstream projection correction scheme is to form a camera-projector system by binding a camera to the pro-jector,performing software correction to pre-wrapping the projected picture.Due to the characteristics of the ultra-short focus of the laser TV,it is difficult for the camera installed on the laser TV to capture the full frame,which makes it difficult to construct a traditional camera-projector system.This paper proposes a novel projection correction scheme for laser TV.The proposed scheme uses a smart phone to build a camera-projector system,completing projection correction by means of adjusting the laser TV's pose through a 6-DOF pose adjustment platform.Compared with the traditional scheme,the proposed scheme has the following advantages: 1 Retain the picture quality of the laser TV completely without deforming and cutting the picture? 2 Make full use of the users' existing computing resources.Move the computer vision processing and the pose inverse solution calculation of the mechanism to the mobile phone? 3 Make full use of the users' existing mobile phone camera to avoid additionally installing a camera or other sensers in laser TV or adjustment platform?4 Have no preset for the size and projection instincts of the laser TV,thus can adjust universally for all laser TVs on the market.Main work of this paper:(1)The mechanism of laser TV projection correction through posture adjustment was studied.First,use the pinhole camera model to geometrically model the laser TV.Then use the screen-picture homography matrix in multiple poses to calibrate the laser TV's instincts and use the laser TV's instincts and screen-picture homography transformation matrix to perform real-time pose estimation of the laser TV,using two or more known adjustment platform poses and the estimated laser TV pose to estimate the environment parameters of the adjustment platform base in the world coordinate system.Finally,solve the ideal pose of the laser TV and the corresponding pose of the adjustment platform and drive the adjustment platform to drive the laser TV to the ideal pose,thereby achieving projection correction.(2)We compare several different 6-DOF mechanisms and select 3PPSR as the pose adjustment mechanism of laser TV,performing kinematics inverse solution and working space simulation analysis.We also study the influence of different xy platform arrangement and different design size on the working space,confirming the main design size that meets the adjustment platform travel requirements.(3)Aiming at the problem of obtaining the screen-projection picture homography transformation relationship from the image,we design a special calibration image.The specialized calibration image maps the color channel difference into the gray space,im-proving the speed and accuracy of obtaining the image form the video stream and calcu-lating the homography matrix through fuzzy screening,Otsu threshold segmentation and other processes,which has laid a good foundation for the instincts calibration and pose estimation of the laser TV.(4)An implementation of software and hardware is given.We use STC89C52 as the control chip to build an embedded system,which communicates with the mobile phones via Bluetooth.Through using Flutter to build mobile phone applications,we realizes func-tions such as adjusting platform state maintenance and pose inversion,extracting feature of screens and projection pictures,solving homography matrix,maintaining Bluetooth state and so on.