Controlling an Industrial Robot Using a Graphic Tablet in Offline and Online Mode

The article presents the possibility of using a graphics tablet to control an industrial robot. The paper presents elements of software development for offline and online control of a robot. The program for the graphic tablet and the operator interface was developed in C# language in Visual Studio environment, while the program controlling the industrial robot was developed in RAPID language in the RobotStudio environment. Thanks to the development of a digital twin of the real robotic workstation, tests were carried out on the correct functioning of the application in offline mode (without using the real robot). The obtained results were verified in online mode (on a real production station). The developed computer programmes have a modular structure, which makes it possible to easily adapt them to one’s needs. The application allows for changing the parameters of the robot and the parameters of the path drawing. Tests were carried out on the influence of the sampling frequency and the tool diameter on the quality of the reconstructed trajectory of the industrial robot. The results confirmed the correctness of the application. Thanks to the new method of robot programming, it is possible to quickly modify the path by the operator, without the knowledge of robot programming languages. Further research will focus on analyzing the influence of screen resolution and layout scale on the accuracy of trajectory generation.

Decrease Selected Graphomotor Skills in Early Stages of Alzheimer's Dementia

IntroductionIn the early stages of Alzheimer's disease (AD) motor and cognitive dysfunctions has been observed.ObjectivesIn previous studies we have shown that AD patients present abnormalities of selected graphomotor skills, but results were vary and not conclusive. In this study, we conducted more extensive tests on a larger study group.AimsThe aim of the study is to identify which graphomotor functions are impaired in the early stages of AD.MethodsSeventy-one patients with mild and moderate AD (F.00.0, F.00.1, F.00.2) (MMSE 20.3 ± 3.8; age 79.1 ± 5.21) were examined. Forty-four healthy ones (C) without symptoms of dementia, matched for demographic characteristics (MMSE 29 ± 1.1; age 78.3 ± 4.7) were examined. Graphomotor skills were assessed by the original drawing test (the eight figures and the signature) performed in a magnetic field (resolution 2540 dpi and 1024 pressure levels). These test were implemented on a graphic tablet (Wacom Intuos) with the specialized software. The length and time of drawing, the average and maximum speed of drawing, the average and maximum momentary speed, the amplitude and frequency (with FFT spectrum analysis) of hand tremors were measured.ResultsStatistical analysis of the graphomotor signal revealed differences between the AD group and the C group with respect to various parameters. The largest differences have been observed in partially automated skills such as signature, and not drawing shapes (lines, spiral, etc.). The average speed of signature and maximum momentary speed of signature is lower in the AD group.ConclusionsThis method allows for quantitative and objective measurement of the biophysical signal and assessment of the graphomotor skills.Disclosure of interestThe authors have not supplied their declaration of competing interest.

Preserved Adjustment but Impaired Awareness in a Sensory-Motor Conflict following Prefrontal Lesions

Control of action occurs at different stagesof the executive process, in particular at those of sensory-motor integration and conscious monitoring. The aim of this study was to determine the implication of the prefrontal cortex in the control of action. For that purpose, we compared the performance of 15 patients with frontal lobe lesions and 15 matched controls on an experimental paradigm generating a conflict between the action planned and the sensory-motor feedback. Subjects had to trace a sagittal line witha stylus on a graphic tablet. The hand was hidden by a mirror on which the traced line, processed by a computer, was projected. Without informing the subjects, the line traced was modified by introducing a bias to the right, which increased progressively from 2° to 42°. To succeed the task, subjects had to modify their motor program and deviate their hand in the opposite direction. The sensory-motor adjustment to the bias was evaluated by the surface between the line traced and the ideal line to compensate for the deviation. The awareness of the conflict was measured by the angle of the bias at which subjects expressed the feeling that the line they traced was not the same as the line they saw. The deviation was similarly compensated for by patients and controls until24°. Then 14 controls but only3 patients were aware of a conflict. After that, the variability of performance increased significantly for the unaware patients. These results suggest that the prefrontal cortex is required at the level of conscious monitoring of actions, but not at the level of sensory-motor integration.