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A magnetic-wheeled robot is a type of robot that inspects large steel structures instead of humans, and it can run on a three-dimensional path by using wheels with built-in permanent magnets. For the robots to work safely, their magnetic wheels require both magnetic attractive forces and friction forces. Planetary-geared magnetic wheels, which we have developed, make direct contact with their yokes on the running surface to ensure their magnetic attractive force. However, this design decreases their frictional performance more than common magnetic wheels covered with soft materials. Therefore, the yokes require methods that can improve their frictional performance without decreasing their attractive force. To consider the best method for the use of magnetic wheels, this study has run experiments with five types of yokes, which have different processing. As a result, the yokes with corroded surfaces could have maintained the attractive force more than 90% of the time and increased their traction forces by about 36% in static conditions and about 30% in dynamic conditions compared to yokes with no machining. The main reasons for these experimental results are that the rust layer has stable irregularities on the surface and includes ferromagnetic materials.

To discuss and consider the necessary conditions for magnetic-wheeled robots with planetary-geared magnetic wheels, this paper provides comparing static calculations about three orientations in running a flange with real experiments. SCPREM-I, a magnetic-wheeled robot, was developed for running through a flange from the bottom to the top. This robot has four magnetic wheels with a built-in planetary gearset. In experiments, however, the robot sometimes fails to run through a flange in three orientations. In this study, we statically analyze SCPREM-I to find the conditions necessary for running through the flange. We calculate the forces around the front and rear wheels in the three orientations. As a result, it has been found that the chassis of the SCPREM-I applies a forward force to the wheels when it runs through the flange. In addition, it has been found that the normal force of the A-Legs is balancing with the driving force of the wheels when the SCPREM-I fails to run through the flange.

ABSTRACT Tilapia gonads mature quickly before reaching market size, caused by a diverting of feed energy from growth to reproduction. As a result, somatic growth is disrupted to achieve market size, the operational costs are high, and the rearing period is longer. This study aims to evaluate the ability of karamunting leaf extracts to inhibit the development of tilapia gonads. This study used a complete randomized design with four treatments and three replications, namely 0 mg/kg, 25 mg/kg, 50 mg/kg, and 100 mg/kg of karamunting leaf extract. Tilapia fish weighed 13–14 g were kept in an aquarium measuring 100×60×50 cm with a stocking density of 20 fish/ aquarium. Fish were fed twice a day at 8 a.m and 5 p.m in at satiation. Sampling was carried out at the beginning of the study, on day 30th and day 60th. On day 30th the result showed that the best dose in inhibiting the development of fish gonad was 100 mg/kg of karamunting leaf extract that was 1.15 ± 0.19% and the daily growth rate was increased at 2.22 ± 0.06%. On day 60th, the best dose in inhibiting gonad development was 25 mg/kg of karamunting leaf extract, which was 2.49 ± 1.24% and the daily growth rate was increased amount 3.26 ± 0.06%. Keywords: extract, karamunting leaves, gonad development, tilapia ABSTRAK Gonad ikan nila cepat berkembang sebelum mencapai ukuran pasar, menyebabkan pengalihan energi pakan dari pertumbuhan ke reproduksi. Akibatnya, pertumbuhan somatik terganggu sehingga untuk mencapai ukuran pasar biaya operasional tinggi dan masa pemeliharaan lebih lama. Penelitian ini bertujuan untuk mengevaluasi ekstrak daun karamunting dalam menghambat perkembangan gonad ikan nila. Penelitian ini menggunakan rancangan acak lengkap dengan empat perlakuan dan tiga ulangan; yaitu 0 mg/kg, 25 mg/kg, 50 mg/kg, dan 100 mg/kg ekstrak daun karamunting. Ikan nila berukuran 13–14 g dipelihara di akuarium berukuran 100×60×50 cm dengan padat tebar 20 ikan/akuarium. Ikan diberi makan dua kali sehari pada jam 8 pagi dan 5 sore dengan at satiation. Pengambilan sampel dilakukan pada awal penelitian, hari ke-30 dan hari ke-60. Hasil pada hari ke-30 menunjukan bahwa dosis terbaik dalam menghambat perkembangan gonad pada ikan uji adalah 100 mg/kg ekstrak daun karamunting yaitu 1.15 ± 0.19% dan meningkatkan pertumbuhan harian 2.22 ± 0.06%. Pada hari ke-60 dosis terbaik dalam menghambat perkembangan gonad adalah 25 mg/kg ekstrak daun karamunting yaitu 2.49 ± 1.24% dan meningkatkan pertumbuhan harian 3.26 ± 0.06%. Kata kunci: daun karamunting, ekstrak, ikan nila, pertumbuhan gonad

In recent years, the deterioration of many bridges built during the period of rapid economic growth has become a problem. As a solution of it, preventive measures such as visual inspections and repairs by humans have been taken, but these methods have problems in terms of cost and safety. If inspection by robots becomes possible, both of these problems will be improved and it is expected to contribute greatly to the maintenance and management of bridges. Therefore, a number of robots have been developed for the purpose of bridge inspection. The among such inspection robots, wire-driven robots, which have less risk of falling and can perform close proximity or contact inspection, are attracting attention. However, one of the problems with this type of robot is that it is difficult to place the wire under the bridge when there is a river or road underneath it, or when it is very high. Thus, in this study, a shooting device for shooting arrows with attached strings was developed to solve this problem. We then conducted a shooting experiment and confirmed that the device aimed at the target automatically and shot the arrow. In addition, we created a simulation model of an arrow with a string attached to it to obtain information such as the shooting angle of the arrow in advance. Then, the flight trajectory and horizontal flight distance of the arrows were compared between the actual and simulated data, and the consistency was confirmed.

A robotic fish is ideal for an ecological survey of underwater life, because underwater animals cannot easily notice the robot. However, when a robotic fish swings its body to swim, it makes a rolling motion due to movements of the center of gravity and this rolling motion has a bad influence on the coordinate calculation of the tracking target, therefore it is necessary to correct the image. The robot has FPGA (Field Programmable Gate Array) and it is suitable for real-time image processing because FPGA has excellent performance with its parallel processing. In this study, we create a program to calculate the roll angle of the robot by using the gyro and acceleration sensor mounted on the robot and to correct the image by rotating it by that angle. Then, we conduct an evaluation of this rotation correction method with rotation tester that reproduces the rolling motion of the robotic fish and determine synchronization timing of image data and angle data because the CMOS camera used for the robot adopts rolling shutter method. Furthermore, we investigate the effect on coordinate calculation by the fish robot with created program. We have confirmed that this robot can perform real-time correction of rotated image and reduce the influence on the coordinate calculation of the target.

In recent years, the deterioration of infrastructure facilities such as bridges has become a problem. Precautionary measures such as visual inspections and repair by humans are in place as countermeasures for aging, but there are problems with cost and safety in such inspections. If inspection by robots becomes possible, both will be improved, which will greatly contribute to the maintenance of infrastructure facilities. In this paper, we propose a localizational position specifying system for a robot supporting bridge inspection of the moving robot under the bridge to support inspection of the bridge. Since the robot must travel on the steel structures at the bottom of the bridge, strong permanent magnets need to be installed on the edge parts in the wheels. Also, it is not possible to receive the coordinate information from the satellite as it travels at the bottom of the bridge. Therefore, a 1-dimensional low-cost LiDAR sensor and a stepping motor are used to implement as a planar LiDAR sensor which rotates 360 degrees, specify the position of the current robot by obtaining distance and direction data from fixed feature points. The localizational position specification through the planar LiDAR are examined by the experiment. As a result, it was possible to estimate the localizational position of the robot.

In Japan, the disruption of ecosystems caused by alien fish in lakes and ponds is a major issue. To address this problem, we propose that the robotic fish COMET can assist in alien fish extermination by adding the function of spear shooting. The way of extermination is that when COMET finds an alien fish, let COMET approach an alien fish without being wary it and spear it. In this study, we investigated the spear shooting process under different movement conditions to determine the impact on the accuracy of the trajectory of the spear. The results confirmed that a certain set of conditions can improve the accuracy of hitting the target with a spear using specific movements of the robotic fish.

The objectives of this study were to investigate the normal histological localization of aquaporin (AQP) 5 protein in the lacrimal and nictitating membrane glands and to compare this localization in healthy and keratoconjunctivitis sicca (KCS) dogs. Lacrimal and nictitating membrane glands of 5 healthy Beagles and nictitating membrane glands of 5 KCS dogs (3 Beagles and 2 mongrel dogs: 0–13 years) were used for the present study. The owners of the KCS dogs did not consent to perform biopsies of the lacrimal glands. The localization and distribution of AQP5 protein were investigated by an immunohistochemical technique. In immunohistochemical staining, AQP5 was localized in the apical site of acinar epithelial and ductal epithelial cells from both the lacrimal and nictitating membrane glands in healthy dogs. However, AQP5 was not detected in the 5 KCS dogs. These results for immunohistochemical AQP5 localization might correlate with the deficiency in tear secretion found in KCS dogs. [ABSTRACT FROM AUTHOR]