A new type of energy harvester for traffic induced bridge vibrations

Energy harvesters subtract energy from their surroundings and convert this to electrical energy. Even though energy output is generally low, energy harvesters can offer great value by offering the possibility of self-sustaining devices, combined with the developments in low power semiconductors. Many examples can be found of applications that...

Design and tuning of a bi-stable compliant mechanism: For use in energy harvesting using frequency up conversion

Vibration energy harvesting is a growing field of research. Harvesting energy from vibrations can be of use in devices in hard to reach places, such as sensors on a train track or a pacemaker. These devices makes use of batteries, which need to be replaced. Using energy harvesting this battery life could be improved. <br/>The difficulty lies in...

Tuning the Dynamics of Bistable Mechanisms by Introducing Travel Limits

Vibrations are a promising source for powering wireless sensors, for example in low-frequency environments like human motion. These environments suffer from unpredictable vibration spectra and their low-frequency and large amplitude characteristics offer great possibilities for mechanisms with double well potential energy characteristics. The...

Manipulating the stiffness of post-buckled beams using topology optimization

Vibration energy harvesters can help in different areas. These vary from supplying power to medical implants or wireless sensors that can aid in predicting natural disasters. However, the problem is that they are not able to generate power across a large bandwidth of frequencies. Bistable energy harvesters can solve this problem when these are...

Piezoelectric energy harvesting from low frequency vibrations

Vibration energy harvesters have been proposed as a solution to increase the lifetime of wireless and portable medical devices. One example of implantable medical devices for which energy harvesters could be interesting, are pacemakers. With a lifespan of about 6 to 12 years, the battery must be replaced after this period of time. Using an...

Micro Energy Harvesting from Low-Frequency Vibrations: Towards Powering Pacemakers with Heartbeats

Miniaturized vibration energy harvesters can provide an alternative to batteries in powering the billions of low power devices we use today by extracting power from ambient motion. Especially for implanted medical devices, these alternative power sources may be an attractive option to overcome the limitations on longevity and the replacement...

A plucking based frequency up-converted vibration energy harvesting method: Design and model of a new frequency up-converted energy harvesting method

Vibration energy harvesting has proven to be a durable source of energy for a wide variety of applications, however not all of the positions these applications are placed at are suitable for conventional vibration energy harvesting. For some of these applications a frequency up-converted energy harvester could increase the power harvested. These...

Design of travel limits for bistable vibration energy harvesting

Energy harvesting from renewable energy sources has become more popular in the last decades than ever before. New energy sources consisting of human input vibrations are hopeful alternatives for powering wearable low power electronics. These sensors currently rely on the lifetime of the battery and come along with high maintenance costs in case...

On the efficiency of coupled vs uncoupled vibration energy harvesters under transient excitations

Vibration energy harvesters are especially interesting to use in an environment where there is one dominant vibration frequency present because then the harvesters can be designed to resonate at that specific frequency. To spread out the power yield over more frequencies a multi-modal harvester can be used which can resonate at multiple...

Stiffness compensation for piezoelectric energy harvesting: Improving the efficiency at low-frequency vibrations

In the field of vibration energy harvesting, vibration energy is tranduced to electrical energy to power small, low powered devices. Many energy harvesters are produced in the form of a resonator, where resonant amplification enables efficient operation of the energy harvester. At low frequencies below 10 hz, input motions quickly increase for a...

Manipulating post-buckled compliant mechanisms: Buckling mode interaction as a novel method of stiffness compensation

Bistable vibration energy harvesters are an interesting alternative to their linear counterparts. They allow for large amplitude oscillations between their stable equilibria, from which much energy can be generated. However, the stable equilibria are separated by a potential energy barrier that has to be overcome. Therefore, we cannot guarantee...

A stiffness compensated piezoelectric energy harvester for low-frequency excitation

In this work, a stiffness compensated piezoelectric vibration energy harvester is modelled and tested for low-frequency excitations and large input amplitudes. Attracting magnets are used to introduce a negative stiffness that counteracts the stiffness of the piezoelectric beam. This results into a nearly statically balanced condition and...

Correct examination of vibration energy harvester perfromance

Vibration energy harvesting can become a durable source of energy for wireless<br/>sensors or other low power applications like pacemakers. Huge savings in ecological footprint, production and maintenance costs can be achieved by replacing batteries for vibration energy harvesters. Most of the time, newly developed energy harvesters are tested...

Optimization of Cantilever-Shaped Piezoelectric Energy Harvester: with the Application of Mechanical Stoppers

Energy harvesting has become a popular topic for battery substitution in recent years. In particular, mechanical vibrational energy, one of the most common energy sources, has been intensely studied. Piezoelectric materials play a crucial role in vibrational energy harvesting as they can directly convert the mechanical energy to the desired...

Vibration Energy Harvesting from Human Motion: by Frequency up-conversion through Impact

Vibration Energy Harvesting has the potential to become a convenient, sustainable and localized power source for the billions of small electronic devices of the future. One of the most challenging areas within this field is the design of miniaturized generators for power harvesting from human motion. In this thesis, a new strategy, design and...