Towards a self-deploying and gliding robot

Strategies for hybrid locomotion such as jumping and gliding are used in nature by many different animals for traveling over rough terrain. This combination of locomotion modes also allows small robots to overcome relatively large obstacles at a minimal energetic cost compared to wheeled or flying robots. In this chapter we describe the development of a novel palm sized robot of 10\,g that is able to autonomously deploy itself from ground or walls, open its wings, recover in midair and subsequently perform goal- directed gliding. In particular, we focus on the subsystems that will in the future be integrated such as a 1.5\,g microglider that can perform phototaxis; a 4.5\,g, bat-inspired, wing folding mechanism that can unfold in only 50\,ms; and a locust-inspired, 7\,g robot that can jump more than 27 times its own height. We also review the relevance of jumping and gliding for living and robotic systems and we highlight future directions for the realization of a fully integrated robot

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

Bioinspired Jumping Locomotion for Miniature Robotics

In nature, many small animals use jumping locomotion to move in rough terrain. Compared to other modes of ground locomotion, jumping allows an animal to overcome obstacles that are relatively large compared to its size. In this thesis we outline the main design challenges that need to be addressed when building miniature jumping robots. We then present three novel robotic jumpers that solve those challenges and outperform existing similar jumping robots by one order of magnitude with regard to jumping height per size and weight. The robots presented in this thesis, called EPFL jumper v1, EPFL jumper v2 and EPFL jumper v3 have a weight between 7g and 14.3g and are able to jump up to 27 times their own size, with onboard energy and control. This high jumping performance is achieved by using the same mechanical design principles as found in jumping insects such as locusts or fleas. Further, we present a theoretical model which allows an evaluation whether the addition of wings could potentially allow a jumping robot to prolong its jumps. The results from the model and the experiments with a winged jumping robot indicate that for miniature robots, adding wings is not worthwhile when moving on ground. However, when jumping from an elevated starting position, adding wings can lead to longer distances traveled compared to jumping without wings. Moreover, it can reduce the kinetic energy on impact which needs to be absorbed by the robot structure. Based on this conclusion, we developed the EPFL jumpglider, the first miniature jumping and gliding robot that has been presented so far. It has a mass of 16.5g and is able to jump from elevated positions, perform steered gliding flight, land safely and locomote on ground with repetitive jumps1. ______________________________ 1See the collection of the accompanying videos at http://lis.epfl.ch/microglider/moviesAll.zi

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

Transient bio-inspired gliders with embodied humidity responsive actuators for environmental sensing

Collecting temporal and spatial high-resolution environmental data can guide studies in environmental sciences to gain insights in ecological processes. The utilization of automated robotic systems to collect these types of data can maximize accuracy, resilience, and deployment rate. Furthermore, it reduces the risk to researchers deploying sensors in inaccessible environments and can significantly increase the cost-effectiveness of such studies. The introduction of transient robotic systems featuring embodied environmental sensors pushes towards building a digital ecology, while introducing only minimal disturbance to the environment. Transient robots made from fully biodegradable and non-fossil based materials, do not develop into hazardous e-waste at the end of their lifetime and can thus enable a broader adoption for environmental sensing in the real world. In this work, our approach towards the design of transient robots includes the integration of humidity-responsive materials in a glider, which is inspired by the Alsomitra macrocarpa seed. The design space of these gliders is explored and their behavior studied numerically, which allows us to make predictions on their flight characteristics. Results are validated against experiments, which show two different gliding behaviors, that can help improve the spread of the sensors. By tailoring the Cellulose-Gelatin composition of the humidity actuator, self-folding systems for selective rainwater exposure can be designed. The pH sensing layer, protected by the actuator, provides visual feedback on the pH of the rainwater. The presented methods can guide further concepts developing transient aerial robotic systems for sustainable, environmental monitoring