Beijing Institute of Technology

Ruili Jia

Chunguang Xu

Yuren Lu

Peng Yin

Shuangyi Li

Wenyuan Song

Dezhi Li

Jianfeng Song

Juan Hao

Canzhi Guo

Wanxin Yang

Xianchun Xu

Xinhao Zheng

Zhixiang Li

An ultrasonic testing system of dual robot arms and an ultrasonic testing method for use in testing quality of surface and interior of a workpiece. The system includes an extension rod provided between a tail-end of a master robot arm and an emitting probe and/or between a tail-end of a slave robot arm and a receiving probe. One or more connected extension rod rotating shafts is provided between the extension rod and the emitting probe or between the extension rod and the receiving probe. The method uses an X-axis constraint method to convert posture data of the discrete points in a trajectory file of the tested workpiece into Euler angles, and constrain the X-axes of the auxiliary coordinate systems at the same time so that the positive direction of the X-axis of each of the auxiliary coordinate systems is the trajectory tangent direction.

Ultrasonic testing system of dual robot arms and method thereof

The present disclosure is related to the technical field of propellant performance research, and in particular, to a method for reducing propellant curing residual stress by a high-energy acoustic beam. The method includes the following steps: injecting a propellant slurry into a curing container and waiting for the propellant slurry to start curing; actuating, when the propellant slurry starts curing, a high-energy acoustic beam generator and a high-energy acoustic beam transducer to continuously emit high-energy acoustic beam to the propellant slurry in the curing container until the propellant slurry is cured to form a propellant grain; and closing the high-energy acoustic beam generator and the high-energy acoustic beam transducer. The method for reducing propellant curing residual stress by high-energy acoustic beam provided in the present disclosure can reduce residual stress inside the propellant in an effective manner, thereby ensuring operation safety of the aerospace equipment.

Method for reducing propellant curing residual stress by high-energy acoustic beam

The present disclosure provides a device and a method for reducing and homogenizing residual stress during machining in which a workpiece is fixed, such as milling, boring, drilling and planning, with which high-energy acoustic waves are emitted to the workpiece via a tight contact between a plurality of high-energy wave exciters on a bench and a workpiece coated with a coupling medium, and residual stress inside the machined workpiece is reduced and homogenized through elastic wave energy generated in the workpiece by the high-energy acoustic waves. In this way, the purpose of reducing and homogenizing the residual stress while machining is achieved, realizing a stress-free machining, and the deformation of the workpiece during and after machining is minimized.

Device and a method for reducing and homogenizing residual stress of a workpiece generated during machining

A device and method for reducing and homogenizing residual stress of a component by an array of high-energy elastic waves. The device includes a tubular body consisting of at least two elements, multiple first through holes and a clamping device provided on an outer side of the tubular body. Exciters are connected with exciting wedges so that an end face of each of the exciting wedges is closely coupled to a surface of the component. A connection portion is coupled to an emitting end of each of the exciters, where the axis of the emitting end coincides with a normal line at a pressed surface of the component A multi-channel signal amplifier is electrically connected to each of the exciters and a multi-channel excitation control module is electrically connected to the multi-channel signal amplifier.

Device and method for reducing and homogenizing residual stress of a component by array of high-energy elastic waves

The present disclosure relates to the technical field of non-destructive detecting of residual stress, and in particular to a non-destructive detecting device for component residual stress gradient. the non-destructive detecting device comprises: groups of transmitting transducers and receiving transducers arranged symmetrically to each other, the transmitting transducers closer to the symmetry axis have greater excitation frequencies; an acoustic wedge coupled to the groups of transmitting transducers and receiving transducers, wherein groups of cylindrical transmitting tunnels and receiving tunnels are provided obliquely within the transmitting connection area and the receiving connection area through their top surfaces and toward their bottom surfaces, the transmitting transducers are coupled to the transmitting tunnels in a one-to-one correspondence, the receiving transducers are coupled to the receiving tunnels in a one-to-one correspondence, and the bottom surfaces of the transmitting connection area and the receiving connection area are pressed against the surface of the detected component; and a calculation processing module electrically connected to the transmitting transducers and the receiving transducers. The non-destructive detecting device solves the problem that the residual stress values of components at different penetration depths cannot be detected at the same time.

Non-destructive detecting device for component residual stress gradient

An ultrasonic testing device that can make a robotic testing system reach the surface of a complex curved composite workpiece that is not easy to reach and perform a quality testing. By pumping a coupling liquid into the device so that the coupling liquid enters a waveguide and jets onto the surface of the workpiece, an ultrasonic wave can be transmitted in the waveguide and reach the surface of the workpiece and penetrate the workpiece, thereby achieving the purpose of quality testing of the workpiece. By providing two ultrasonic testing devices without a waveguide on both sides of a tested workpiece, respectively, and by mounting the waveguide on one side or both sides of the ultrasonic testing devices, it is possible to transmit the ultrasonic waves to the surface of the workpiece or to receive the ultrasonic waves from the surface of the workpiece.

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Beijing, China

Ruili Jia