63results about How to "Easy to measure on site" patented technology

The invention discloses a method and a device for measuring the wood density of a standing tree, and relates to the technical field of measurement. The method comprises the steps of: measuring the diameter of a part to be measured at a first height from the ground of the standing tree; transmitting and receiving microwaves within a preset frequency range at a first distance in the air; measuring afirst ratio of transmitted microwave signals to first received microwave signals at different frequencies; transmitting microwaves at a first height in the air to allow the microwaves to penetrate the part to be measured of the standing tree, receiving the microwaves at a first distance from the microwave transmitting position, and measuring a second ratio of the transmitted microwave signals tosecond received microwave signals at different frequencies; calculating a dielectric constant and an attenuation constant of the standing tree according to the first ratio, the second ratio and the diameter; and determining a relational expression among the wood density of the standing tree, the dielectric constant and the attenuation constant, and calculating the wood density of the standing treeaccording to the relational expression. By adopting the measurement method disclosed by the embodiment of the invention, the measurement accuracy of the wood density is improved.

The invention discloses a roll angle measuring method based on a grating and a device thereof, which belongs to the technical field of photoelectric detection. A laser lases and emerges directly, or emerges after collimation through a collimating lens; the light is directly incident on a one-dimensional plane transmission grating, or reversely incident on the grating through a retrodirective reflector; plus-minus first stage diffracted light from the grating is focused to form two diffracted light points through a lens; a photodetector is used to detect the variations in positions of the two focused light points, thus figuring out a roll angle. The optical structure of the device is compact and simple, and brings convenience to practice; in addition, the accuracy, the stability and the economical efficiency are also high. The grating is used as a sensitive device; error separation is achieved, and the interference-free feature is improved by using the differential measurement of doublediffracted beams; few optical devices are used; and the power of the light source is low; the cost is low; mobile parts do not require to be provided with cables; the angle measurement distinguishability is as high as 0.5 and even higher; different requirements of measurement accuracy can be met just by replacing the grating with gratings having different numbers of lines.

A multi-freedom laser measuring system is composed of laser emitter, polarizing-splitting unit, 4-freedom error sensing unit, photoelectric receiver unit and signal processing unit. Said 4-freedom error sensing unit consists of quater-wavelength wave plate, optical splitter and optical reflector. The laser beam is splitted into the perpendicular mutually linear polarized light beams in two polarizing directions. The light beam received by said 4-freedom error sensing unit is splitted to two beans received by two photoelectric receiver. The linearity error of an object in two directions and the pitch angle error can be obtained after signal processing.