Autonomous Environment Recognition by Robotic Manipulators

This paper discusses methods of autonomus environment recognition and action by a robotic manipulator working with dynamic interaction to the enviroment, e.g., assembling. A method automatically recognizes the contacting situation with the work site from the sensor outputs and the robotic manipulator motion. The autonomous recognition then discriminates the constraint conditions at manopulator hand using the self-organizing map that is a kind of unsupervisedlearning of neural networks. The discrimination of the constraint conditions is successfully demonstraed by a numerical simulation of a 3-link SCARA type manipulator. Another is for the cognitive action. Some approaches based on the reinforcement learnin are proposed. They give models of cognitive actions and aproaches to so-called frame problem obstructing efficient learning and action

A study toward cognitive action with environment recognition by a learning space robot

金沢大学工学部泉田, 啓This paper addresses an experimental system simulating a free-flying space robot, which has been constructed to study autonomous space robots. The experimental system consists of a space robot model, a frictionless table system, a computer system, and a vision sensor system. The robot model is composed of two manipulators and a satellite vehicle, and can move freely on a two-dimensional planar table, without friction, using air-bearings. The robot model has successfully performed the automatic truss structure assembly, including many jobs, e.g., manipulator berthing, component manipulation, arm trajectory control collision avoidance, assembly using force control, etc. Moreover, even if the robot fails in a task planned in advance, the robot re-plans the task by using reinforcement learning, and obtains the task goal for basically kinematic problems. But, for a class of complicated dynamic problems, the computational periods and efforts are infeasible for on-line learning. Some approaches are proposed to accelerate the learning speed, which also give models of cognitive actions and approaches to so-called a frame problem. The experiment demonstrates the possibility of the autonomous construction and the usefulness of space robots

<b>Variation of the critical power model parameters in response to kayak training </b>

This study proposed to verify the sensibility of the critical power model parameters in response to training load variation during a kayaking competitive season. Eleven young male kayakers participated of this study. They were evaluated at the end of each of three mesocycles, as follows: (M1) characteristically aerobic; (M2) characteristically aerobic-anaerobic and; (M3) characteristically anaerobic and velocity, just before competition. Critical velocity (CV) and kayaking anaerobic capacity (ACkayak) were estimated from the results of three distance tests (500, 1,000 e 1,800 m) covered in the minimal possible time. The ACkayak did not change after the three mesocycles (M1: 91.4 ± 32.0 m; M2: 89.,0 ± 50.8 m e; M3: 74.0 ± 44.2 m). In contrast, CV improved from M1 (3.19 ± 0.28 m.s-1) to M2 (3.33 ± 0.28 m.s-1), and became stable in M3 (3.32 ± 0.19 m.s-1). The results indicated that CV is sensible to training effects, and it can be used to control for aerobic training adaptations. RESUMO O objetivo deste estudo foi averiguar a sensibilidade dos parâmetros do modelo de potência crítica, em resposta às oscilações nas cargas de treinamento, ao longo de uma temporada competitiva de canoagem. Participaram deste estudo 11 canoístas jovens, do sexo masculino, os quais foram avaliados ao final de cada um de três mesociclos seguidos, sendo: (M1) após mesociclo de característica aeróbia; (M2) após mesociclo de característica mista aeróbia-anaeróbia e; (M3) após mesociclo de característica anaeróbia e de velocidade, o qual antecedia a competição. Nos três momentos, foram determinadas a velocidade crítica (VCrit) e a capacidade anaeróbia da canoagem (CACanoagem) por meio de três distância fixas (500, 1.000 e 1.800 m), percorridas no menor tempo possível. A CACanoagem não foi alterada ao longo dos três mesociclos estudados (M1: 91,4 ± 32,0 m; M2: 89,0 ± 50,8 m e; M3: 74,0 ± 44,2 m). Já a VCrit foi melhorada de M1 (3,19 ± 0,28 m/s) para M2 (3,33 ± 0,28 m/s), mantendo-se estável em M3 (3,32 ± 0,19 m/s). Os resultados apontam que a VCrit é uma variável sensível aos efeitos do treinamento, e pode ser utilizada no monitoramento das adaptações aeróbias ao treinamento

Behavior of the muscle strength and arm muscle area during 24 weeks of weight training

http://dx.doi.org/10.5007/1980-0037.2008v10n4p379 The purpose of this study was to analyze the behavior of muscle strength and arm muscle area (AMA) over 24 weeks of weight training (WT) as well as to establish possible associations between these variables. The sample was composed of 18 men aged between 18 and 30 years. Measurements of relaxed arm circumference and triceps skinfold measurement were used for the calculation. Muscle strength was assessed using the one-repetition maximum test (1-RM) on the arm curl exercise. The WT protocol lasted 24 weeks, divided into 3 stages (F1, F2, and F3) of 8 weeks each. It is important to emphasize that every measurement was made before, during and after the end of the WT period. Analysis of variance (ANOVA) for repeated measures followed by the Tukey post hoc (P < 0.05) was used to the compare the indicators of muscle strength and muscle hypertrophy. Pearson’s correlation coefficient was used to verify possible association between muscle strength and AMA. Muscle strength and AMA increased continuously throughout the whole period except for the initial period (F1). Therefore, it is concluded that the initial phase of training, neuromuscular adaptation, seems to have been the turning point for increase in muscle strength. After that, the hypertrophy process appears to gradually become the essential factor for increase in muscle strength

Comparação entre limiar anaeróbio determinado por variáveis ventilatórias e pela resposta do lactato sanguíneo em ciclistas

Many investigations have shown that the coincidence between the ventilatory thresholds and those thresholds using the lactate response does not happen all of the time, suggesting that there is no relationship between the cause-effect between these phenomena. Thus, the present study had as main purpose to compare and correlate the Oxygen consumption (V̇O 2), the power (W), and the heart rate (HR) values attained using protocols to determine the Ventilatory Threshold (VT) and the Individual Anaerobic Threshold (IAT). The sampling was constituted by eight State and National level cyclists (age: 27.88 ± 8.77 years; body mass: 65.19 ± 4.40 kg; height: 169.31 ± 5,77 cm). The IAT was determined starting from a three minutes 50 W warm up with progressive increases of 50 W.3min -1 up to achieving the voluntary exhaustion, when the blood was collected in the last 20 seconds of each phase, and during the recovering period. In order to determine the VT, it was used the same protocol used to determine the IAT, but without performing the blood collection. The VT was identified through the changes in the pulmonary ventilation, as well as of the ventilatory equivalent of the O 2 and CO 2. The t-Student test showed no significant statistical difference in any of the attained variables. The associations found were high and significant. The V̇O 2 (ml.kg -1.min. -1), P (W), and HR (bpm) corresponding to the VT and IAT, as well as the associations between variables were respectively: 48.00 ± 3.82 vs. 48.08 ± 3.71 (r = 0.90); 256.25 ± 32.04 vs. 246.88 ± 33.91 (r = 0.84); 173.75 ± 9.18 vs. 171.25 ± 12.02 (r = 0.97). According to the results attained, it can be concluded that the IAT and the VT produce similar V̇O 2, W, and HR values, favoring the adoption of the VT because it is a non-invasive method to determine the anaerobic threshold in cyclists