In this paper we develop an elasto-dynamic model of the human arm for use in neuro-muscular control and dynamic interaction studies. The motivation for this work is to present a case for developing and using non-quasistatic models of human musculo-skeletal biomechanics. The model is based on hybrid parameter multiple body system (HPMBS) variational projection principles. In this paper, we present an overview of the HPMBS variational principle applied to the full elasto-dynamic model of the arm. The generality of the model allows one to incorporate muscle effects as either loads transmitted through the tendon at points of origin and insertion or as an effective torque at a joint. Though the technique is suitable for detailed bone and joint modeling, we present in this initial effort only simple geometry with the bones discretized as Rayleigh beams with elongation, while allowing for large deflections. Simulations demonstrate the viability of the method for use in the companion paper and in future studies.

In this paper we develop an elasto-dynamic model of the human arm that includes effects of neuro-muscular control upon elastic deformation in the limb. The elasto-dynamic model of the arm is based on hybrid parameter multiple body system variational projection principles presented in the companion paper. Though the technique is suitable for detailed bone and joint modeling, we present simulations for simplified geometry of the bones, discretized as Rayleigh beams with elongation, while allowing for large deflections. Motion of the upper extremity is simulated by incorporating muscle forces derived from a Hill-type model of musculotendon dynamics. The effects of muscle force are modeled in two ways. In one approach, an effective joint torque is calculated by multiplying the muscle force by a joint moment arm. A second approach models the muscle as acting along a straight line between the origin and insertion sites of the tendon. Simple arm motion is simulated by utilizing neural feedback and feedforward control. Simulations illustrate the combined effects of neural control strategies, models of muscle force inclusion, and elastic assumptions on joint trajectories and stress and strain development in the bone and tendon.

The pitching-down flapping is a new type of bionic flapping, which was invented by the author based on previous studies on the aerodynamic mechanisms of fruit fly (pitching-up) flapping. The motivation of this invention is to improve the aerodynamic characteristics of flapping Micro Air Vehicles (MAVs). In this paper the pitching-down flapping is briefly introduced. The major works include: (1) Computing the power requirements of pitching-down flapping in three modes (advanced, symmetrical, delayed), which were compared with those of pitching-up flapping; (2) Investigating the effects of translational acceleration time, Δτ_t  and rotational time, Δτ_r , at the end of a stroke, and the angle of attack, α, in the middle of a stroke on the aerodynamic characteristics in symmetrical mode; (3) Investigating the effect of camber on pitching-down flapping. From the above works, conclusions can be drawn that: (1) Compared with the pitching-up flapping, the pitching-down flapping can greatly reduce the time-averaged power requirements; (2) The increase in Δτ_t  and the decrease in Δτ_r can increase both the lift and drag coefficients, but the time-averaged ratio of lift to drag changes a little. And α has significant effect on the aerodynamic characteristics of the pitching-down flapping; (3) The positive camber can effectively increase the lift coefficient and the ratio of lift to drag.

In dry attachment systems of spiders and geckos, van der Waals forces mediate attraction between substrate and animal tarsus. In particular, the scopula of Evarcha arcuata spiders allows for reversible attachment and easy detachment to a broad range of surfaces. Hence, reproducing the scopula’s roughness compatibility while maintaining anti-bunching features and dirt particle repellence behavior is a central task for a biomimetic transfer to an engineered model. In the present work we model the scopula of E. arcuata from a mechano-elastic point of view analyzing the influence of its hierarchical structure on the attachment behavior. By considering biological data of the gecko and spider, and the simulation results, the adhesive capabilities of the two animals are compared and important confirmations and new directives in order to reproduce the overall structure are found. Moreover, a possible suggestion of how the spider detaches in an easy and fast manner is proposed and supported by the results.

Mosquitoes are exceptional in their ability to pierce into human skin with a natural ultimate painless microneedle, named fascicle. Here the structure of the Aedes albopictus mosquito fascicle is obtained using a Scanning Electron Microscope (SEM), and the whole process of the fascicle inserting into human skin is observed using a high-speed video imaging technique. Direct measurements of the insertion force for mosquito fascicle to penetrate into human skin are reported. Results show that the mosquito uses a very low force (average 18 μN) to penetrate into the skin. This force is at least three orders of magnitude smaller than the reported lowest insertion force for an artificial microneedle with an ultra sharp tip to insert into the human skin. In order to understand the piercing mechanism of mosquito fascicle tip into human multilayer skin tissue, a numerical simulation is conducted to analyze the insertion process using a nonlinear finite element method. A good agreement occurs between the numerical results and the experimental measurements.

Unpredictable air movements have proved to be a problem in previous studies investigating robot communication by means of airborne pheromone chemicals. The project described in this paper investigates the use of air vortex rings as a means of carrying pheromone chemicals between transmitting and receiving robots. Sensitivity to chemicals including pheromones released by conspecifics is essential for many aspects of an insect’s life. They assist in finding food, locating a mate, avoiding danger and help coordinate the activities of social insects. In the future, autonomous robots will be challenged by many situations similar to those that face insects and other simple creatures. Chemical communication may prove useful for these robots as well. This paper describes the equipment developed for generating and detecting vortex rings. Results of experiments involving location and tracking of a sequence of pheromone vortex rings are also presented.

Multiple Uninhabited Aerial Vehicles (multi-UAVs) coordinated trajectory replanning is one of the most complicated global optimum problems in multi-UAVs coordinated control. Based on the construction of the basic model of multi-UAVs coordinated trajectory replanning, which includes problem description, threat modeling, constraint conditions, coordinated function and coordination mechanism, a novel Max-Min adaptive Ant Colony Optimization (ACO) approach is presented in detail. In view of the characteristics of multi-UAVs coordinated trajectory replanning in dynamic and uncertain environments, the minimum and maximum pheromone trails in ACO are set to enhance the searching capability, and the point pheromone is adopted to achieve the collision avoidance between UAVs at the trajectory planner layer. Considering the simultaneous arrival and the air-space collision avoidance, an Estimated Time of Arrival (ETA) is decided first. Then the trajectory and flight velocity of each UAV are determined. Simulation experiments are performed under the complicated combating environment containing some static threats and popup threats. The results demonstrate the feasibility and the effectiveness of the proposed approach.

A robotic fish driven by oscillating fins, “Cownose Ray-I”, is developed, which is in dorsoventrally flattened shape without a tail. The robotic fish is composed of a body and two lateral fins. A three-factor kinematic model is established and used in the design of a mechanism. By controlling the three kinematic parameters, the robotic fish can accelerate and maneuver.  Forward velocity is dependent on the largest amplitude and the number of waves in the fins, while the relative contribution of fin beat frequency to the forward velocity of the robotic fish is different from the usual result. On the other hand, experimental results on maneuvering show that phase difference has a stronger effect on swerving than the largest amplitude to some extent. In addition, as propulsion waves pass from the trailing edge to the leading edge, the robotic fish attains a backward velocity of 0.15 m•s^-1.

Laser multiple processing, i.e. laser surface texturing and then Laser Shock Processing (LSP), is a new surface processing technology for the preparation of bionic non-smooth surfaces. Based on engineering bionics, samples of bionic non-smooth surfaces of stainless steel 0Cr18Ni9 were manufactured in the form of reseau structure by laser multiple processing. The mechanical properties (including microhardness, residual stress, surface roughness) and microstructure of the samples treated by laser multiple processing were compared with those of the samples without LSP. The results show that the mechanical properties of these samples by laser multiple processing were clearly improved in comparison with those of the samples without LSP. The mechanisms underlying the improved surface microhardness and surface residual stress were analyzed, and the relations between hardness, compressive residual stress and roughness were also presented.

Extenics is a newly developed interdisciplinary subject combining mathematics, philosophy and engineering. It provides useful formalized qualitative tools and quantitative tools for solving contradictory problems. In this paper, extension theory is introduced briefly and the primary applications of this theory and methods in bionic engineering research are discussed. The extension model of biological coupling functional system is established. In order to identify the primary and secondary sequencing of coupling elements, the Extension Analytic Hierarchy Process (EAHP) was adopted to analyze the contribution of each coupling element to the coupling functional system. Thus, the influence weight factor of each coupling element can be determined, so as to provide a new approach for solving primary and secondary sequencing problem of coupling elements in a quantitative way, and facilitate the subsequent bionic coupling study.

We present a rapid system for predicting beef tenderness by mimicking the human tactile sense. The detection system includes a FS pressure sensor, a power supply conversion circuit, a signal amplifier and a box in which the sample is mounted. A sample of raw Longissimus dorsi (LD) muscle is placed in the measuring box; then a rod connected to the pressure sensor is pressed into the beef sample to a given depth; the reaction force of the beef sample is measured and used to predict the tenderness. Sensory evaluation and Warner-Bratzler Shear Force (WBSF) evaluation of samples from the same LD muscle are used for comparison. The new detection system agrees with established procedure 95% of the time, and the time to test a sample is less than 5 minutes.