Energy-regenerative Shock Absorber Research Articles

Energy regenerative shock absorber based on a slotted link conversion mechanism for application in the electrical bus to power the low wattages devices

In recent years, using electric buses based on sustainable energy technologies has become very popular due to their advantages of protecting the environment from hazardous pollutants. However, the power supply of electric buses is the most challenging issue and hinders it from making efficient electric buses. In this study, an energy regenerative shock absorber (ERSA) was designed to be employed in the electric bus to harvest kinetic energy from rough road profiles and enhance the efficiency of electric buses. The proposed ERSA is based on a slotted link conversion mechanism to convert linear vibrations to unidirectional rotations of the generator shaft for energy harvesting and comprises four modules: the energy input model, the motion converter model, the model of a generator, and the electrical energy storage model. Firstly, the energy input model induced vibration into the proposed shock absorber; the motion converter model converts linear vibrations to unidirectional rotations using a slotted link conversion mechanism to drive the generator. Subsequently, the generator model generated electric energy stored in the power storage model. The theoretical model was developed, and simulations were performed using MATLAB software; after that, the real-scale prototype was evaluated through an experimental study using a mechanical bench test (MTS machine) under similar parameters. An average output power of 6.591 W with an efficiency of 39.37% was achieved. Moreover, the ERSA system showed a maximum efficiency of 67.7% during sinusoidal excitations of 7.5 mm and 2.5 Hz. Furthermore, the feasibility analysis was conducted to verify the suitability of the proposed system for powering the auxiliary devices in the electric bus. The suggested ERSA can reasonably power light detection, range sensors, stereo vision cameras, an inertial measurement unit, an accelerometer, and a global navigation satellite system.

Energy harvester using two-phase flow conditions

Single-phase flow-induced vibration energy harvesting approaches, such as vortex-induced vibration, galloping, and flutter, have received considerable attention from researchers in recent years. However, the challenges and potential applications of multi-phase flow-induced vibration energy harvesting have rarely been explored. To bridge the research gap in the present energy harvesting studies based on two-phase flow, we investigated in detail the mechanism and potential benefits of the fluid–structure interaction between smart structures and two fluid phases (water and air) on the vibration energy harvesting performance. A piezoelectric energy harvester using air–water two-phase flow conditions is proposed for potential multifunctional applications. A T-shaped piezoelectric cantilever was used to harvest liquid sloshing energy in the proposed structure. A fluid–structure interaction containing two fluid phases (water and air) was theoretically modelled using the arbitrary Lagrangian-Eulerian technique. The experimental results showed that a prototype of the proposed structure can be used as a smart water bottle that simultaneously performs human-motion energy collection and acts as a drinking water bottle. The prototype achieved its maximum peak-to-peak voltage value (12.08 V) at 5 km/h for powering wireless IoT (Internet of Things) nodes. Furthermore, it can be used as an energy regenerative shock absorber to perform the dual functions of vibration damping and energy harvesting. Therefore, multi-phase flow-induced vibration energy harvesting shows great application potentials.

A novel energy regenerative shock absorber for in-wheel motors in electric vehicles

As the demand for energy harvesting increases, regenerative shock absorbers have received more attention in expanding the cruising range of electric vehicles. The current study proposes a novel design of regenerative shock absorber for the in-wheel motor to capture the vibration energy from the rough road surface while driving an electric vehicle. The regenerative shock absorber design mainly focuses on vibration capture, motion transmission, and generator modules. The motion-capture module collects the irregular vibrations caused by the roughness of the road surface. The motion transmission module transfers linear motion to unidirectional rotational motion, which is then converted to electrical power in the generator module by mechanical gears and clutches. The purpose of using an auxiliary generator is to improve production capacity while also controlling the damping process of the shock absorber. Also, the inclusion of a supercapacitor and voltage regulator improves the stability of the charging circuit. An electro-mechanical Instron testbed was employed for the experimental study to verify the simulated results and found a good agreement. The experimental results demonstrated that the generated power from two generators was >380 W with an efficiency of 62%. The proposed regenerative shock absorber is effective and feasible for renewable energy applications in electric vehicles.

Investigation on energy-regenerative shock absorber with adjustable damping and power for freight wagons

Due to lack of power supply, the onboard monitoring and intelligent devices applied in unpowered freight wagons require manual periodic battery replacement. Converting and utilizing local vibration energy is an effective means to realize the self-power of nearby onboard devices. In this paper, a compact energy-regenerativeshockabsorber with nut-screw transmission and novel unidirectional rotation converter is proposed for harvesting energy from suspension vibration of freight wagons. In addition, an interface circuit with voltage control loop implements the adjustment of system damping and power. With two given policies of control loop reference value, the absorber presents two mechanical characteristics: variable damping and constant damping. The overall system is modelled with dynamic characteristic of diodes considered, and the numerical simulation errors in absorber reaction force and the power obtained by DC/DC are reduced by 48% and 66%. In lab tests, the maximum average efficiencies of DC/DC converter and the whole system are 87.66% and 42.6%. A maximum charging power of 9 W is obtained at the normal suspension vibration excitation, and the average charging power can achieve 87% of that at ideal impedance matching. Meanwhile, the system damping characteristics and power generation capacity under the influence of voltage control loop and external excitation are investigated systematically. By vehicle-track dynamics analysis, the influence law of absorber on freight wagon vibration characteristics is revealed versus different circuit loads. This energy-regenerative damping system possesses adjustable damping and power by the control of circuit load, which will have notable superiority in adapting to the mechanical constraints and power requirements of more engineering application scenarios.

A high-efficiency energy regenerative shock absorber for powering auxiliary devices of new energy driverless buses

Many countries are gradually adopting the latest energy driverless buses to reduce harmful environmental emissions, mainly in the transportation sector. The power supply is the main obstacle to developing new energy driverless buses while assuming the absence of battery technology advances. This paper proposes a new energy regenerative shock absorber to capture the wasted kinetic energy of the vehicle suspension system and produces electrical power. The regenerative shock absorber is divided into four modules: vibration energy capture module, motion conversion module, generator module and electric energy storage module. The random vibration of suspension, caused by certain factors, such as rugged roads and speed variation, acts on the vibration energy capture module. The motion conversion module mainly consists of two helical racks with opposite threads and converts the bidirectional vibration into unidirectional rotation of the generator. The utilization of helical gears with different diameters makes the damping coefficients different, so that the regenerative shock absorber can take full advantage of elastic elements to improve vehicle comfort during compression strokes, and quickly absorb vibration during extension strokes. The generator module generates electricity and the electric energy storage module accumulates the electricity in the supercapacitor. A prototype was fabricated, and the power generation performance of the regenerative shock absorber was evaluated by bench test under different sinusoidal excitations. At input sinusoidal displacement of 7 mm and 2.5 Hz frequency, the average output power of 4.25 W and maximum and average efficiencies 65.02% and 39.46% were calculated. The results demonstrate that the designed regenerative shock absorber can effectively scavenge renewable energy and apply it to the new energy driverless buses.

A high-efficiency energy regenerative shock absorber using helical gears for powering low-wattage electrical device of electric vehicles

In this paper, a regenerative absorber based on helical gears and dual tapered roller clutches is presented for electric vehicles. The absorber can scavenge energy that dissipated in the suspension from vibrations induced by the road roughness. To achieve this, three parts are necessary in the proposed absorber, which are the suspension vibration input module, the transmission module and the generator module. These are installed between the chassis and the axle. The suspension vibration input module transmits kinetic energy to the transmission module, and moves the shafts bi-directionally. The transmission module consists of helical gears and one-way clutches, and converts the bi-directional shaft motion to unidirectional motion for a motor. The generator module generates electric energy to power the low-wattage electrical device of electric vehicles. The characteristics of this homemade prototype containing different helical gear angles are studied using a Mechanical Testing and Sensing test fixture. A peak efficiency of 52% and an average efficiency of 40% are demonstrated in the bench tests, verifying that the proposed regenerative absorber is effective and practical for renewable energy applications in electric vehicles.

A Theoretical and Simulation Performance Study of Hydraulic Electric Energy Regenerative Shock Absorber

To enhance the fuel economy of automobile and extend the thermal fatigue duration of the typical shock absorbers, energy regenerative shock absorbers have enticed huge attention. Hydraulic electric energy-regenerative shock absorber (HERSA) is a new kind of shock absorber which can regenerate an amount of energy, dissipated as the heat energy in traditional shock absorber. This paper briefly describes HERSA’s working principle, uses AMESim (hydraulic simulation software) to get damping attribute of HERSA as properly as conventional shock absorber through some theoretical and simulation tests. On the basis of simulation outcomes, we differentiate the hydraulic electric energy regenerative shock absorber (HERSA) and traditional shock absorber, and the results revealed that the inclusive performance of the prior is higher to that of the recent, but it shows the theoretical possibilities of HERSA’s structure to improve fuel economy and ride comfort.

Energy-regenerative Shock Absorber Mathematical Model

Tough environmental requirements, which are applicable for modern automobiles in the leading countries, make it an urgent task to implement energy efficiency technologies in the design of newly created vehicles. One of the factors enhancing transport efficiency is to introduce the suspension system based on the energy-regenerative shock absorber which converts mechanical losses in the suspension into electric energy by means of the electromechanical converter (generator). Hence, the development of the mathematical model for the energy-regenerative shock absorber based on the AC generator with permanent magnet excitation and installed into the suspension system of the energy efficient vehicle is a relevant issue. The article presents the mathematical model of the energy-regenerative shock absorber designed on the basis of the AC generator with a permanent magnet excitation. The math model is necessary to research electromechanical and energy processes as well as to determine the main design characteristics, electrical specification and shock absorber operation conditions.

Design, Modeling, and Analysis of a Novel Hydraulic Energy-Regenerative Shock Absorber for Vehicle Suspension

To reduce energy consumption or improve energy efficiency, the regenerative devices recently have drawn the public’s eyes. In this paper, a novel hydraulic energy-regenerative shock absorber (HERSA) is developed for vehicle suspension to regenerate the vibration energy which is dissipated by conventional viscous dampers into heat waste. At first, the schematic of HERSA is presented and a mathematic model is developed to describe the characteristic of HERSA. Then the parametric sensitivity analysis of the vibration energy is expounded, and the ranking of their influences is k1≫m2>m1>k2≈cs. Besides, a parametric study of HERSA is adopted to research the influences of the key parameters on the characteristic of HERSA. Moreover, an optimization of HERSA is carried out to regenerate more power as far as possible without devitalizing the damping characteristic. To make the optimization results more close to the actual condition, the displacement data of the shock absorber in the road test is selected as the excitation in the optimization. The results show that the RMS of regenerated energy is up to 107.94 W under the actual excitation. Moreover it indicates that the HERSA can improve its performance through the damping control.

A high-efficiency energy regenerative shock absorber using supercapacitors for renewable energy applications in range extended electric vehicle

The energy source of vehicles is changing rapidly and significantly in recent years with the increase in renewable energy technologies especially in the case of electric vehicles (EVs). A smart solution has emerged in which the wasted energy in a vehicle’s shock absorber is converted to an alternative energy for the cars themselves, and this is called an energy regenerative shock absorber. Whereas existing regenerative shock absorbers mainly focus on the methods of energy harvesting, there is no such regenerative shock absorber for use in extended range EVs. In this paper, we present a novel high-efficiency energy regenerative shock absorber using supercapacitors that is applied to extend the battery endurance of an EV. A renewable energy application scheme using regenerative shock absorbers for range extended EVs is designed and proposed for the first time. This system collects the wasted suspension power from the moving vehicle by replacing the conventional shock absorbers as these energies are normally dissipated through friction and heat. The proposed system consists of four main components: the vibration of the suspension input module, transmission module, generator module and power storage module. The suspension vibration induced by the road roughness acts as the system excitation to the energy regenerative shock absorber. The vibration is then transmitted through the mechanical transmission module, which changes bidirectional vibration into unidirectional rotation based on gears and a rack to drive the generator module. The power storage module stores the regenerative energy of the shock absorber in the supercapacitor, which is applied to the EV to improve the cruising mileage. Higher efficiency up to 54.98% at most and 44.24% on average were achieved in the simulation and bench tests is proof that the energy regenerative shock absorber is beneficial and promising in generating energy used for renewable energy applications in extended range EVs.

Energy-Regenerative Shock Absorber for Transportation Vehicles Based on Dual Overrunning Clutches: Design, Modeling, and Simulation

This paper presents the design, modeling, and simulation of an energy-regenerative shock absorber based on dual overrunning clutches for transportation vehicles, to enable energy harvesting from suspension vibration. The energy-regenerative shock absorber consists of three main components: the suspension vibration input, the transmission module, and the generator module. The innovative design of the shock absorber uses dual overrunning clutches, which can convert oscillatory vibration into unidirectional rotation of the generator. The dynamic modeling of the shock absorber is presented to analyze damping characteristics. Simulations were performed to demonstrate the performance of the proposed energy-regenerative shock absorber. A peak output power of 44.73 W and an average power of 22.34 W were attained from this proposed shock absorber at a vibrational input of 2-Hz frequency and 20-mm amplitude. The prototype can achieve 69.19% efficiency at 1-Hz frequency and 15-mm amplitude. The results show that variable damping coefficients are achieved by changing the external load of the shock absorber. As a result, the energy-regenerative shock absorber can be applied to different types of transportation vehicles.

A Novel Energy-Harvesting Active Radial Bogie for Railway Vehicles: Design, Simulation and HIL Test

With the increasing development of railway transportation, the wheel-rail wearing problem is becoming more and more serious while the increasing of both the operating speed and loading weight of railway vehicles. Active radial bogie is one of the hotspots for research in the area of decreasing the wheel-rail wearing issues. Meanwhile, the energy dissipation problem has been restricting its development. This paper puts forward a novel energy-harvesting active radial bogie for rail vehicles. Making use of the hydraulic electromagnetic energy-regenerative shock absorber, the vertical vibration energy could be harvested while train is traveling. Detailed study and evaluation for this active radial bogie will be presented. The tests and simulation results prove the effectiveness of the proposed bogie mechanism and control.

Simulation Study of Permanent Magnet Synchronous Motor for Hydraulic Electromagnetic Energy-Regenerative Shock Absorber

Hydraulic electromagnetic energy-regenerative shock absorber (HESA) which used one permanent magnet synchronous motor (PMSM) as actuator to regenerate energy is introduced in this paper. Mathematic model which transform a three phase time and speed dependent system into a two co-ordinate time invariant system is presented. To obtain better dynamic performance, simulation models on a PMSM with field oriented control (FOC) have been carried out. Rapid torque response and stable dynamic performance are verified through the simulation results.

An Optimal Algorithm for Energy Recovery of Hydraulic Electromagnetic Energy-Regenerative Shock Absorber

This paper presents a new kind of shock absorber, hydraulic electromagnetic energy-regenerative shock absorber (HESA), which can recover energy from vibration of vehicles. The road excitation frequency, load resistance and damping ratio are found to greatly affect the energy recovery of HESA. Based on a quarter-car model, the optimal load resistance and damping ratio for maximizing the energy-recyclable power are discussed. The results indicate that f or any excitation frequency, the energy-recyclable power first increases then decreases with the load resistance increase, and the optim al load resistance is changeable as the excitation frequency changes. Moreover, the energy-recyclable power is more sensitive to excitation frequency than to damping ratio, and the ideal excitation frequency for energy recovery is around the wheel resonant frequency. The exploration of active control of HESA confirms that the damping force varies with the load current magnitude, and the active control can be realized by appropriate matching.

Performance Simulation of Hydraulic Energy-Regenerative Shock Absorber

This paper presents several kinds of energy-regenerative shock absorbers, which all exist some problems. Then, we put forward a novel type of shock absorber: Hydraulic Energy-regenerative Shock Absorber (HESA). In this paper, we focus on damping characteristic and energy recovery of HESA. Its feasible that damping force can be increased by adding a damping orifice in the extension stroke. The damping characteristic of HESA meets the requirements, whats more, it has great potential on energy recovery.

A Study on the Theory and Performance Simulation of the Hydraulic Electromagnetic Energy-Regenerative Shock Absorber

Hydraulic electromagnetic energy-regenerative shock absorber (HESA) is a new type of shock absorber which can regenerate a portion of energy dissipated as thermal energy in conventional shock absorber. This paper briefly describes HESAs working principle, uses AMESim, a hydraulic simulation software, to get damping characteristic of HESA as well as conventional passive shock absorber by doing some simulation tests, and contrasts the two consequents. Simulation results show that HESA has its unique damping characteristic, and its regenerative characteristic performs well.

The Operating Principle and Experimental Verification of the Hydraulic Electromagnetic Energy-Regenerative Shock Absorber

This paper introduces a new type of shock absorber: hydraulic electromagnetic energy-regenerative shock absorber (HESA), which can simultaneously implement the function of damping vibration and regenerating a portion of dissipated energies generated from passing through the damping hole. A test bench was trial-produced and used to prove the feasibility of the energy-regenerative scheme. The situation that hydraulic motor rotational speed has a sudden change in the energy regenerating process is theoretically analyzed.

Researching on Valve System of Hydraulic Electromagnetic Energy-Regenerative Shock Absorber

Hydraulic electromagnetic energy-regenerative shock absorber is a new kind of shock absorbers, who can perform the function of a standard shock while acting as an additional source of power. One of the core components of this new shock absorber is the valve system. And its function is to rectify the direction of the oil flow. Then the oil can flow through the hydraulic motor from one port only no matter in expansion stroke or compression stroke. The research focused on the compactness, sensitivity and energy recovery rate of two different valve systems. And the results showed that the valve system composed of check valves better matched the hydraulic electromagnetic energy-regenerative shock absorber.