Realization of three-dimensional walking of a cheetah-modeled bio-inspired quadruped robot

Adaptability of quadruped animals is not solely reached by brain control, but by the interaction between its body, environment, and control. Especially, morphology of the body is supposed to contribute largely to the adaptability. We have tried to understand quadrupedal locomotion by building a bio-inspired quadruped robot named ”Pneupard”, which has a feline-like muscular-skeletal structure. In our previous study, we successfully realized alternative gait of hindlimbs by reflex control based on the sole touch information, which is called an unloading rule, and that of forelimbs as well. In this paper, we finally connect forelimbs and hindlimbs by a rigid spine, and conduct 3D walking experiments only with the simple unloading rule. Through several preliminary experiments, we realize that the touch information on the sole is the most critical for stable 3D walking.This work was partially supported by Grant-in-Aid for Scientific Research on 23220004, 25540117 of Japan.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1109/ROBIO.2014.7090426

Stable reflex-based walking of forelimbs of a bio-inspired quadruped robot-modeled cheetah

In contrast to the high movement adaptability of quadruped animals in many environmental conditions, it is hard for conventional quadruped robots to operate in complex environment conditions. We investigate the adaptability of animals’ musculo-skeletal systems, by building a bio-inspired quadruped robot named ”Pneupard” which duplicates a feline musculo-skeletal system. In this study, we built Pneupard’s forelimb which has 14 active muscles, 4 passive muscles and 8 degrees of freedom (DOF). We propose sole reflex-based control and verify its effectiveness by conducting walking experiments, in which the robot performed stable walking with a two-dimensional restriction.This work was partially supported by a Grant-in-Aid for Scientific Research(23220004) from the Japanese Ministry of Education, Culture, Sports, Science and Technology.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1109/ROBIO.2013.673973

Producing alternating gait on uncoupled feline hindlimbs: Muscular unloading rule on a biomimetic robot

Studies on decerebrate walking cats have shown that phase transition is strongly related to muscular sensory signals at limbs. To further investigate the role of such signals terminating the stance phase, we developed a biomimetic feline platform. Adopting link lengths and moment arms from an Acinonyx jubatus, we built a pair of hindlimbs connected to a hindquarter and attached it to a sliding strut, simulating solid forelimbs. Artificial pneumatic muscles simulate biological muscles through a control method based on EMG signals from walking cats (Felis catus). Using the bio-inspired muscular unloading rule, where a decreasing ground reaction force triggers phase transition, stable walking on a treadmill was achieved. Finally, an alternating gait is possible using the unloading rule, withstanding disturbances and systematic muscular changes, not only contributing to our understanding on how cats may walk, but also helping develop better legged robots.The authors acknouledge the Japanese Research Grant KAKENHI Kiban 23220004 and 25540117.This is the author accepted manuscript. The final version is available from Taylor & Francis via http://dx.doi.org/10.1080/01691864.2013.87049

Exploring muscular contribution during stepping of biomimetic feline hindlimbs

Although robotic locomotion have greatly advanced over the past years, the abyss that separates such locomotion from even the simplest animal locomotions prompt us to approach robotic locomotion taking cues from animals. The animal musculoskeletal structure, often ignored by roboticists due to its high redundancy and complexity, might hold the secret for self-stable locomotion observed in bipeds and quadrupeds. Aiming to better understand how muscles contribute to selfstable locomotion we take the feline structure as a model on a biomimetic approach. Using 6 air muscles per hindlimb to mimic real muscles, this robot walks stably on a treadmill while supported by a slider, simulating forelimbs. We individually evaluate muscle contribution to walking stability, performing a comparison between mono and biarticular synergistic muscles at the ankle and concluding that a higher compliance on the biarticular muscle improved walking stability. A better understanding of such complex phenomena may help on the development of better legged robots in the future, truly taking advantage of concepts developed by nature over the years.This work was partially supported by KAKENHI Kiban(S) 23220004.This is the accepted manuscript. The final version is available at http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=6739573&tag=1

Pneupard: A biomimetic musculoskeletal approach for a feline-inspired quadruped robot

Feline locomotion combines great acrobatic proficiency, unparalleled balance and higher accelerations than other animals. Capable of accelerating from 0 to 100 km h−1 in three seconds, the cheetah (Acinonyx jubatus) is still a mystery which intrigues scientists. Aiming for a better understanding of the source of such higher speeds, we develop a biomimetic platform, where musculoskeletal parameters (range of motion and moment arms) from the biological system can be evaluated with air muscles within a lightweight robotic structure. We performed experiments validating the muscular structure during a treadmill walk, successfully reproducing animal locomotion while adopting an EMG based control method.This work was partially supported by KAKENHI Kiban(S) 23220004.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1109/IROS.2013.6696540

Quadrupedal locomotion based on a muscular activation pattern with stretch-reflex

Cyclical locomotion, such as walking, hopping and running, is known to be generated at the spinal cord, guiding human and animal strides over different gaits. Over the last years, many researchers concentrated their study on the origin of such signals, replicating them by either controlling joint angles or torques. In this work, we use a quadruped pneumatic robot to reproduce stable walking on a treadmill through a muscular activation pattern. Unlike previous studies, neither angles or torques are taken into consideration. Similarly to biological morphology, with variating moment arms, muscles contract rhythmically and their inherent compliance adapts to the floor. Proportional feedback upon touching the floor (stretch-reflex) is also tested, and its effects are explained. In the future, this methodology can be used to produce adaptive gait and improve current robotic by exploring interaction between control and soft bodies.This work was aided by KAKENHI Kiban(S) 23220004 and 25540117.This is the accepted manuscript. The final version is available at http://dx.doi.org/10.1109/ROBIO.2014.7090425

Towards Growing Robots: A Piecewise Morphology-Controller Co-adaptation Strategy for Legged Locomotion

Control of robots has largely been based on the assumption of a fixed morphology. Accordingly, robot designs have been stationary in time, except for the case of modular robots. Any drastic change in morphology, hence, requires a remodelling of the controller. This work takes inspiration from developmental robotics to present a piecewise morphology-controller growth/adaptation strategy that facilitates fast and reliable control adaptation to growing robots. We demonstrate our methodology on a simple 3 degree of freedom walking robot with adjustable foot lengths and with varying inertial conditions. Our results show not only the effectiveness and reliability of the piecewise morphology controller co-adaptation (PMCCA) strategy, but also highlight the need for morphological adaptation as a robot design strategy

DLSU Libraries’ Collection Assessment about Philippine Languages Collection and Collection Mapping of Filipino Reference List

This study examines the extent to which the De La Salle University (DLSU) Libraries collect print resources about Philippine languages (more than 70 dialects) and how successfully the DLSU libraries in acquiring resources about Philippine languages. It also gauges how the DLSU libraries support the curriculum of the College of Liberal Arts in terms of its collection. This study employs a descriptive research method. It uses collection assessment or the systematic evaluation of the quality of a library collection to determine the extent to which it meets the library’s service goals and objectives and the information needs of its clientele. Data were extracted and culled from the library’s information system, and tables and percentages were used to describe Philippine languages’ current collection of print resources. The DLSU library has an excellent primary collection of resources about Philippine languages. However, the collection assessment highlights many reference materials can still be acquired from the market and added to the collection. The Filipiniana section was able to establish a decent collection that could cater to the needs of the faculty and students. The library still needs to be aggressive in the acquisition of library materials recommended as required readings in the class syllabi of each course. The result of the study provides a profile of the DLSU libraries’ collection of Philippine languages and the extent of its collection building, and how it supports the curriculum. The result of the study can be used to create a comprehensive collection development plan

Miniaturized solid phase extraction techniques applied to natural products

Natural products are increasingly becoming part of our daily lives through their use in industry, food, as therapeutic agents, etc. To evaluate their possible applications, it is essential to characterize them chemically to explore their potential. Different techniques may be used to characterize natural products, including microextraction techniques. These techniques have been gaining popularity due to the advantages associated with their low use of organic solvents and the small amount of sample used relative to more classical sample preparation techniques. Their application in the extraction of compounds from natural products is still scarce. This manuscript intends to review the most used solid-based miniaturized sample preparation techniques applied to determining compounds in natural products. The main applications of these methodologies will be discussed, with a particular focus on natural product analysis, as well as their advantages and disadvantages over traditionally used sample preparation techniques.info:eu-repo/semantics/publishedVersio