In this paper, we presented a method of using the l as er scanning triangulation for the non-contact 3D surface profile measurement of large-scale object. The characteristic of large-scale object non-contact mea surem...In this paper, we presented a method of using the l as er scanning triangulation for the non-contact 3D surface profile measurement of large-scale object. The characteristic of large-scale object non-contact mea surement is analyzed and the measuring method is proposed. Main factors influenc ing measurement precision such as image distortion and accurate designation of s peckle center are analyzed and methods of solving these problems are proposed. W e designed a combined filter by which the pulse noise and the Gaussian noise of speckle image can be eliminated efficiently. Using the characteristic of intensi ty distribution of laser speckle image we proposed a new approximating method th at could locate the center of laser speckle image at sub-pixel. The auxiliary v ariables are set to linearize the relationship between the image displacement an d the distance, the accurate values of laser triangulation system parameters cou ld be calibrated accurately and the measuring precision is increased remarkabl y. Using the above techniques we designed a measuring system based on laser sc anning triangulation. The results of the experiment show that these methods can raise the measuring precision of large-scale 3D surface profile effectively.展开更多
MY father Héctor Mora is a famous Colombian documentary director,producer,and journalist.He was dubbed“the Google map of his time”and“the one who helped Colombians to see the world”by local media for what he ...MY father Héctor Mora is a famous Colombian documentary director,producer,and journalist.He was dubbed“the Google map of his time”and“the one who helped Colombians to see the world”by local media for what he did.From 1977 to 2001,my father set foot on 107 countries and regions,making 1,250 documentaries,among which 52 are related to China.The programs he made were the first,both in Colombia and in other parts of South America,to depict China.展开更多
文摘In this paper, we presented a method of using the l as er scanning triangulation for the non-contact 3D surface profile measurement of large-scale object. The characteristic of large-scale object non-contact mea surement is analyzed and the measuring method is proposed. Main factors influenc ing measurement precision such as image distortion and accurate designation of s peckle center are analyzed and methods of solving these problems are proposed. W e designed a combined filter by which the pulse noise and the Gaussian noise of speckle image can be eliminated efficiently. Using the characteristic of intensi ty distribution of laser speckle image we proposed a new approximating method th at could locate the center of laser speckle image at sub-pixel. The auxiliary v ariables are set to linearize the relationship between the image displacement an d the distance, the accurate values of laser triangulation system parameters cou ld be calibrated accurately and the measuring precision is increased remarkabl y. Using the above techniques we designed a measuring system based on laser sc anning triangulation. The results of the experiment show that these methods can raise the measuring precision of large-scale 3D surface profile effectively.
文摘MY father Héctor Mora is a famous Colombian documentary director,producer,and journalist.He was dubbed“the Google map of his time”and“the one who helped Colombians to see the world”by local media for what he did.From 1977 to 2001,my father set foot on 107 countries and regions,making 1,250 documentaries,among which 52 are related to China.The programs he made were the first,both in Colombia and in other parts of South America,to depict China.