In view of the stick-slip phenomenon in deep and hard rock drilling, a new type of torsional impactor that can provide torsional impact vibration was designed. According to the working principle and structural characteristics of the designed torsional impactor, this paper theoretically analyzes the influences of different structural parameters and motion parameters on the impact frequency, impact force, and impact torque of the torsional impactor. The results show that the impact frequency f is directly proportional to the rotational speed V_Z of the transmission shaft and the installed number n of torsional impact generating devices. Additionally, the impact force F is directly proportional to sine value of the impact angle α (i.e., sinα), impact hammer mass m, impact hammer rotation speed V_Z (i.e., transmission shaft rotation speed), and impact hammer rotation radius r and is inversely proportional to action time Δt of the impact hammer and impact anvil. Furthermore, the impact torque M is directly proportional to the impact force F and rotary radius r of the impact hammer. This article lays a foundation for further theoretical and experimental research of torsional impactors and provides a reference for the design and testing of torsional impactors.

The manipulator of Explosive Ordnance Disposal (EOD) Robot was taken as the research object; the research was conducted aiming at planning of fetching motion trajectory of manipulator in linkage control. Combined with route requirements of manipulator's fetching operation, the key route points of manipulator end trajectory were set to create a fetching operation trajectory of point-to-point. Based on manipulator positive and inverse kinematics model, using the fold lines trajectory and 6-spline trajectory movement set up and operate a space movement to joint space kinematic characteristics of mapping relations. Under the circumstance of the same location of key points of motion trajectory and the same motion time, computer simulation was performed on the two trajectory planning methods to compare and analyze the motion characteristics like joint angle, angular velocity and angular acceleration of the manipulator. Results revealed that that 6-spline trajectory motion owns more obvious advantages in aspects like reducing manipulator's vibration and improving motion accuracy in the motion process.

In order to study the effect of vacancy defects in different directions and concentrations on the friction force of single crystal iron, Using the process of sliding friction monocrystalline iron matrix with diamond hemispheric probe as the research object, a molecular dynamics model was established and simulated. The results of the study indicate that：The interface barrier potential at the defect of single crystal iron increases the average friction force at the defect, and the friction force of single crystal iron at the defect is greater than that of perfect single crystal iron；The average friction force of single crystal iron increases with the increase of defect concentration; The above research results enrich the theory of friction and wear between the surfaces of the micronanoscale components and provide sufficient theoretical basis and guidance for the design and development of micronanoscale devices.

Based on the mechanical structure of a Delta manipulator with three degrees of freedom, the kinematic characteristics of the parallel manipulator were analyzed, and the vector relation between the static and moving platforms was given. The inverse kinematic function of the three-degree-of-freedom (3-DOF)parallel manipulator was deduced by the vector equation. The simulated forward kinematic solution in the moving platform was carried out by Pro/E modeling software and virtual prototype simulation software ADAMS, which is proved simple. These research contents provide a valuable reference for the adjustment and operation of 3-DOF Delta manipulator prototypes with respect to its dynamic performance, motion track planning, mechanical structure, system control, etc.