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A numerical method to solve the direct kinematics of the 6-PUS parallel robot is presented. This method is based on a simplified geometry of the robot, in such a way that each pair of limbs forms a triangle, the locus of the top vertex of this triangle is an arc. Results of the implementation of the algorithm are presented.

The group of species of Lachnaia tristigma (Lacordaire, 1848) is revised. Previously known taxa and diagnostic characters are reassessed, yielding clear limits for species based on male and female genitalia and not on variable and overlapping external characters. A diagnosis along with figures of the median lobe of aedeagus, endophallus and spermatheca are presented for the previously known species, L. pseudobarathraea Daniel & Daniel, 1898 and L. tristigma, as well as the newly described L. gallaeca n. sp.

Industrial metrology deals with measurements in production environment. It concerns calibration procedures as well as control of measurement processes. Measuring devices have been evolving from manual theodolites, electronic theodolites, robotic total stations, to a relatively new kind of laser-based systems known as laser trackers. Laser trackers are 3D coordinate measuring devices that accurately measure large (and relatively distant) objects by computing spatial coordinates of optical targets held against those objects. In addition, laser trackers are used to align truthfully large mechanical parts. However, such aligning can be done in moving parts, for instance during robot calibration in a welding line. In this case, serial robots are controlled in order to keep a prescribed trajectory to accomplish its task properly. Nevertheless, in spite of a good control algorithm design, as time goes by, deviations appear and a calibration process is necessary. It is well known that laser tracker systems are produced by very well established enterprises but their laser products may result expensive for some (small) industries. We offer two parallel robot-based laser tracker systems models whose implementation would result cheaper than sophisticated laser devices and takes advantage of the parallel robot bondages as accuracy and high payload. The types of parallel robots evaluated were 3-SPS-1-S and 6-PUS. Modelling of the parallel robots was done by analytical and numerical techniques. The latter includes classical and artificial intelligence-based algorithms. The control performance was evaluated between classical and intelligent controllers.