Modelling and investigation on bouncing mechanism of a sphere robot

Spherical rolling mechanisms (SRMs) exhibit a number of advantages with respect to wheeled and legged mechanisms. In fact if the SRM is combined with the power of bouncing mechanism, it will produce an exciting phenomena that can be contributed to applications such as security surveillance, search and rescue. There is not much research done in both fields, especially in the bouncing mechanism. In fact to the best of authors’ knowledge no of research has been done on integrating both mechanism to produce a spherical system that is capable of rolling and bouncing, which can produce a very significant mobile robot. Therefore, this research deals with the modeling and development of a bouncing spherical robot using computational intelligent technique, i.e. Particle Swarm Optimization technique (PSO). A 3D virtual prototype of a spherical robot was developed in Visual Nastran as a platform for input and out data acquisition. Different simulations environment have been created, such as the free fall bouncing, shooting up and projectile type of environment to investigate the bouncing profile affected by different forces. The data obtained were then used for system identification using PSO technique with mean square error (MSE) of 0.0004%. The transfer function representing the bouncing mechanism of the sphere robot was then obtained. Next, the prototype of the sphere robot with bouncing capability was developed. Open loop tests have been conducted and the results show that the hardware developed can produce the bouncing mechanism at its promising capability. Future works need to be conducted to re-visit the hardware, particularly on the body of the sphere robot such that maximum bouncing can be achieved

Role of smartphone devices in motivation to study in the Covid-19 Pandemic

Aims The sudden COVID-19 pandemic experienced globally has caused many schools and institutions of higher learning to resort to fully online teaching and learning throughout the world. Since online teaching is essentially a student-centered learning approach, students’ motivational level plays an important role in making teaching protocols effective. This study aimed to know the level of motivation to study using a smartphone in the COVID-19 pandemic. Instrument & Methods This descriptive study was carried out in 2020 on 75 Indonesian Academy of Administrative Management College students who have smartphones. These students were selected by random sampling method. Data were collected using a researcher�made questionnaire and analyzed by SPSS 17 software using Pearson correlation coefficient and simple linear regression test. Findings There was a positive and significant correlation between the mean score of smartphone usage and the mean score of study motivation (r=0.84; p=0.0001). The effect of smartphone uses on the study motivation in the Covid-19 pandemic was 61.7% (R2=0.617). Conclusion With the increasing use of smartphones, the motivation to learn during pandemic COVID-19 also increased

A simple upper limb rehabilitation trainer

Stroke is a leading cause of disability which can affect shoulder and elbow movements which are necessary for reaching activities in numerous daily routines. To maximize functional recovery of these movements, stroke survivors undergo rehabilitation sessions under the supervision of physiotherapists in healthcare settings. Unfortunately, these sessions may be limited due to staff constraints and are often labor-intensive. There are numerous robotic devices which have been developed to overcome this problem. However, the high cost of these robots is a major concern as it limits their cost-benefit profiles, thus impeding large scale implementation. This paper presents a simple and low cost interactive training module for the purpose of upper limb rehabilitation. The module, which uses a conventional mouse integrated with a small DC motor to generate vibration instead of any robotic actuator, is integrated with a game-like virtual reality system intended for training shoulder and elbow movements. Three games for the module were developed as training platforms, namely: Triangle, Square and Circle games. Results from five healthy study subjects showed that their performances improved with practice and time taken to complete the Triangle game was the fastest of the three

The EPFL jumpglider: A hybrid jumping and gliding robot with rigid or folding wings

Recent work suggests that wings can be used to prolong the jumps of miniature jumping robots. However, no functional miniature jumping robot has been presented so far that can successfully apply this hybrid locomotion principle. In this publication, we present the development and characterization of the ’EPFL jumpglider’, a miniature robot that can prolong its jumps using steered hybrid jumping and gliding locomotion over varied terrain. For example, it can safely descend from elevated positions such as stairs and buildings and propagate on ground with small jumps. The publication presents a systematic evaluation of three biologically inspired wing folding mechanisms and a rigid wing design. Based on this evaluation, two wing designs are implemented and compared

Aerial Locomotion in Cluttered Environments

Many environments where robots are expected to operate are cluttered with objects, walls, debris, and different horizontal and vertical structures. In this chapter, we present four design features that allow small robots to rapidly and safely move in 3 dimensions through cluttered environments: a perceptual system capable of detecting obstacles in the robot’s surroundings, including the ground, with minimal computation, mass, and energy requirements; a flexible and protective framework capable of withstanding collisions and even using collisions to learn about the properties of the surroundings when light is not available; a mechanism for temporarily perching to vertical structures in order to monitor the environment or communicate with other robots before taking off again; and a self-deployment mechanism for getting in the air and perform repetitive jumps or glided flight. We conclude the chapter by suggesting future avenues for integration of multiple features within the same robotic platform

Exploiting the Nonlinear Stiffness of Origami Folding to Enhance Robotic Jumping Performance

This research investigates the effects of using origami folding techniques to develop a nonlinear jumping mechanism with optimized dynamic performance. A previous theoretical investigation has shown the benefits of using a nonlinear spring element compared to a linear spring for improving the dynamic performance of a jumper. This study sets out to experimentally verify the effectiveness of utilizing nonlinear stiffness to achieve optimized jumping performance. The Tachi-Miura Polyhedron (TMP) origami structure is used as the nonlinear energy-storage element connecting two end-point masses. The TMP bellow exhibits a “strain-softening” nonlinear force-displacement behavior resulting in an increased energy storage compared to a linear spring. The geometric parameters of the structure are optimized to improve air-time and maximum jumping height. An additional TMP structure was designed to exhibit a close-to-linear force-displacement response to serve as the representative linear spring element. A critical challenge in this study is to minimize the hysteresis and energy loss of TMP during its compression stage before jumping. To this end, plastically annealed lamina emergent origami (PALEO) concept is used to modify the creases of the structure in order to reduce hysteresis during the compression cycle. PALEO works by increasing the folding limit before plastic deformation occurs, thus improving the energy retention of the structure. Steel shim stock are secured to the facets of the TMP structure to serve as end-point masses, and the air-time and jumping height of both structures are measured and compared. The nonlinear TMP structure achieves roughly 9% improvement in air-time and a 12% improvement in jumping height when compared to the linear TMP structure. These results validate the theoretical benefits of utilizing nonlinear spring elements in jumping mechanisms and can lead to improved performance in dynamic systems which rely on springs as a method of energy storage and can lead to emergence of a new generation of more efficient jumping mechanisms with optimized performance in the future

Using Origami Folding Techniques to Study the Effect of Non-Linear Stiffness on the Performance of Jumping Mechanism

This research uses Origami patterns and folding techniques to generate non-linear force displacement profiles and study their effect on jumping mechanisms. In this case, the jumping mechanism is comprised of two masses connected by a Tachi-Miura Polyhedron (TMP) with non-linear stiffness characteristics under tensile and compressive loads. The strain-softening behavior exhibited by the TMP enables us to optimize the design of the structure for improved jumping performance. I derive the equations of motion of the jumping process for the given mechanism and combine them with the kinematics of the TMP structure to obtain numerical solutions for the optimum design. The results correlate to given geometric configurations for the TMP that result in the two optimum objectives: The maximum time spent in the air and maximum clearance off the ground. I then physically manufacture the design and conduct compression tests to measure the force-displacement response and confirm it with the theoretical approach based on the kinematics. Experimental data from the compression tests show a hysteresis problem where the force-displacement profile exhibits different behavior whether the structure is being compressed or released. I investigate two methods to nullify the hysteresis when compressing or releasing the mechanism and then discuss their results. This research can lead to easily manufacturable jumping robotic mechanisms with improved energy storage and jumping performance. Additionally, I learn more about how to use origami techniques to harness unique stiffness properties and apply them to a variety of scenarios

An overview of waste materials for sustainable road construction

Untreated soil typically has low shear strength, swelling behavior, high compressibility and its characteristics were highly dependent on the environment. In general, such problematic soil will lead to severe damages in road construction industry such as bearing capacity failure, slope instability, and excessive settlement. Agricultural waste, construction waste, and municipal waste have recently gained considerable attention as a sustainable material in road construction application due to its availability, environmental friendly and low-cost materials. Therefore in this review, randomly distributed fiber reinforced soil and oriented distributed fiber reinforced soil will be extensively discussed based on the emerging trend. It further reviewed the feasibility of using waste materials as a reinforcement material for the road construction industry. The review also attempts to evaluate and compare the engineering properties of soil and sustainable materials in order to enhance soil performance as well as help to improve the environment affected by growing waste materials