Coil Spring Research Articles

Keep it simple: correction of anterior cross bite – an ortho-perio interdisciplinary approach

This case report explores the treatment of a 13-year-old male patient with severe dental crowding and periodontal issues using non-extraction orthodontic treatment combined with a root coverage procedure. The patient presented with a skeletal class 1 base malocclusion, and multiple anterior crossbites, along with a compromised lower central incisor and gingival recession. Despite the option of extraction, the patient declined this approach, and the final goal was to achieve stable class 1 occlusion and an improved smile.The treatment plan utilized pre-adjusted edgewise appliance (MBT 0.022 inch slot), distalization of the canine, inversion of the maxillary right lateral bracket, and the cautious use of open coil spring in the upper and lower anterior segments. After alignment was completed, a root coverage procedure was performed on the lower right central incisor. The treatment lasted for 20 months, and the results showed successful alignment of both arches, canine protected occlusion, and improved periodontal health.Overall, this case report highlights the complex relationship between orthodontic treatment and periodontal health and the importance of careful treatment planning and patient communication to achieve successful and stable results. The non-extraction approach combined with root coverage procedure proved to be an effective treatment option for this patient, leading to an improved occlusion, smile, and periodontal health.

Effect of leukocyte platelet-rich fibrin on the rate of canine movement – A prospective and randomized control trial

Objectives: The present study was conducted to investigate the effects of leukocyte and platelet-rich fibrin (L-PRF) on the rate of maxillary canine retraction for a period of 5 months. Material and Methods: A split-mouth study was conducted on 16 patients (32 extraction sockets) (Nine males and seven females; age ranging 17–25 years) with Class II Div 1 malocclusion or Class I bimaxillary protrusion, requiring therapeutic extraction of bilateral maxillary first premolars. After the initial leveling and alignment, L-PRF plugs were placed immediately in the randomly selected socket (Experimental Group) and the other side served as control for secondary healing (Control Group). This was followed by the activation of nickel-titanium closed coil springs for canine retraction. The rate of canine movement, canine rotation, tipping, root resorption, and molar movement was assessed at monthly intervals for 5 months (T0–T5). Data were collected from study models. Assessment of pain accompanying the procedure was done using a Likert scale. The trial was registered at the Clinical Trials Registry of India (REF/2022/02/051837). Results: The study revealed that there was a significant increase in the rate of canine movement on the experimental side in the first 2 months and significant molar anchorage loss was seen only in the 1st month. There were statistically non-significant differences in canine rotation, tipping, probing depth, root resorption, and pain perception between the groups. Conclusion: The use of L-PRF plugs in the extraction sockets enhanced the rate of canine movement in the first 2 months of treatment with less anchorage loss and no deleterious effects on periodontium.

Evaluation of the Effect of Oral Vitamin D3 Supplement on Orthodontic Tooth Movement: A Randomized Clinical Trial Study

Aim: One of the problems that orthodontists commonly face is the prolonged duration of the treatment. Therefore, it is important to find an effective method to increase the rate of orthodontic tooth movement (OTM). This study aimed to evaluate the effectiveness of oral administration of vitamin D3 on OTM rates in humans. Materials and Methods: In this randomized clinical trial study, we selected 29 healthy women aged 18–25 years who sought orthodontic treatment and required bilateral maxillary first premolar extraction. Participants were tested to measure the blood levels of vitamin D3 and, based on the outcomes, were divided into three groups: control (without vitamin D3 deficiency; N = 10), placebo ( N = 9), and experiment ( N = 10), both with vitamin D3 deficiency. Subjects of the last two groups, who were randomly assigned, received 50,000 IU (International Unit) vitamin D3 pearls (Dana Pharmaceutical Company, Tabriz, Iran) or a placebo every 2 weeks for 2 months. Inclusion criteria were patients requiring bilateral extraction of the first premolar in the maxilla. The canines were retracted by nickel-titanium (NiTi) coil springs into the extraction sites. At the beginning, after 1 and 2 months, the distance between canine and lateral teeth on both sides was measured to calculate OTM. Results: In the first month ( t (1–2)), the mean values of OTM in the placebo group were higher than the other groups. However, during the second month ( t (2–3)) and overall ( t (1–3)), the experiment group showed a higher OTM. The experiment and control groups were statistically different in all three time periods ( P-value < .05). The difference between the experiment and placebo groups was only significant in t (2–3) ( P-value < .05). Whereas the placebo and control groups showed a significant difference in t (1–2) ( P-value < .05). Conclusion: Vitamin D3 deficiency seems to increase OTM. Receiving oral supplements of vitamin D3 may not have much effect on increasing the level of vitamin D3. The lowest OTM rate was observed in the control group.

Modelling and experimental characterization of secondary suspension elements for rail vehicle ride comfort simulation

Secondary suspensions play an essential role in the dynamic behaviour of rail vehicles. In particular, they are adopted to reduce the vibrations transmitted to the carbody, thus improving ride comfort. In this paper, an experimental characterization of the viscous damper and coil spring elements composing a vertical secondary suspension is presented. The elements are separately tested with the aim of analysing their dynamic behaviour. Then, modified prototypes are manufactured to reduce the transmitted force. The results of the experimental campaign are later adopted to tune the parameters of the mathematical model of the whole secondary suspension, including the dynamics of both the coil spring and the damper elements. This model allows discussing the effectiveness of the proposed modifications, proving the design of both the components to be fundamental for the improvement of ride comfort.

Dynamics modeling and flight characteristics of folded multi-body aircraft

This paper studies the dynamic modeling method of fold-able multi-body aircraft based on the dynamics theory of multi-body system. Considering the multi-body aircraft as a complete multi-rigid body system, the dynamic model for the free unfolding process of the multi-body aircraft after horizontal launch is established. On the basis of the multi-body dynamics model, the coil spring moment model and the damping moment model for the flexible connection between the flight units are added. Taking a certain type of fold-able three-section wing aircraft as an example, the numerical simulation calculation is carried out. The influence of the flexible connection stiffness coefficient between the flight unit on the dynamic characteristics of the fold-able multi-body aircraft in the free deployment process and the relationship between the stiffness of the flexible connection and the maximum initial folding angle are studied. Finally, the stability envelope between the stiffness coefficient of the flexible connection and the maximum initial folding angle is determined.

Effect of Low level laser on miniscrew displacement during canine retraction: A randomized controlled clinical trial

Background: Anchorage is an important consideration for successful orthodontic treatment. Skeletal anchorage by miniscrews provided better anchorage control then the ordinary extra-oral and intra-oral appliances. However, the stability of the miniscrews is still questionable since they might move under orthodontic loading. Objectives: The aim of this study was to evaluate the effect of Low Level Laser on the miniscrew displacement when subjected to orthodontic force during canine retraction using CBCT. Methods: Twelve patients who required bilateral extraction of upper first premolar and absolute anchorage were recruited from the outpatient clinics of the Department of Orthodontics, Faculty of Dentistry, Beirut Arab University of age ranging 14-28 years. Twenty-four miniscrews were assessed; two miniscrews were inserted into the buccal alveolar bone between the second premolar and first molar on the right and left side for each patient in a 60o oblique direction at the mucogingival junction to avoid root injury. They were divided into 2 sides; test side and a control side, the test side received 4 application of low-level laser therapy during the first twelve days of insertion with a 60 seconds for each application. While the control side did not receive any laser application. After waiting a period of twelve days from miniscrew insertion to allow for soft tissue healing, the upper right and left canines were retracted by 150g of nickel-titanium (NiTi) closed coil springs. A cone-beam computed tomography was taken to evaluate the miniscrew position before application of the force at baseline (T0) and after canine retraction at 6 months (T1). Results: There was no statistically significant difference of miniscrew head and tail displacements of the test side and a sta- tistically significant difference of the heads for the control sides when compared to baseline. Conclusions: Miniscrews used in the current study with the suggested protocol underwent non-significant displacement when using low level laser. The miniscrews remained stable throughout the follow-up period (6 month) without any significant displacement on the test side.

Thermomechanical Characterization and Modeling of NiTi Shape Memory Alloy Coil Spring.

Today, shape memory alloys (SMAs) have important applications in several fields of science and engineering. This work reports the thermomechanical behavior of NiTi SMA coil springs. The thermomechanical characterization is approached starting from mechanical loading-unloading tests under different electric current intensities, from 0 to 2.5 A. In addition, the material is studied using dynamic mechanical analysis (DMA), which is used to evaluate the complex elastic modulus E* = E' - iE″, obtaining a viscoelastic response under isochronal conditions. This work further evaluates the damping capacity of NiTi SMA using tan δ, showing a maximum around 70 °C. These results are interpreted under the framework of fractional calculus, using the Fractional Zener Model (FZM). The fractional orders, between 0 and 1, reflect the atomic mobility of the NiTi SMA in the martensite (low-temperature) and austenite (high-temperature) phases. The present work compares the results obtained from using the FZM with a proposed phenomenological model, which requires few parameters for the description of the temperature-dependent storage modulus E'.

Plastic Shavings by Laser: Peeling Porous Graphene Springs for Multifunctional All-Carbon Applications.

Manufacturing strategies to create three-dimensional (3D) structures with multifunctional nanomaterials are of intense interest for fabricating building blocks in many electromechanical applications. A coil spring composed of graphene provides an important step toward the realization of all-carbon devices, as it is one of the essential elements for a wide range of systems. In this connection, here an unprecedented fabrication strategy to create a new type of 3D coil spring composed of laser-induced graphene springs (LIG-S) which is spontaneously produced via the pyrolytic jetting technique, is presented. Similar to wood or metal shavings observed in traditional machining processes, a pair of LIG-S with two opposite chiralities and controllable macroscopic dimensions is produced by a single scanning of a focused continuous-wave (CW) laser on a polyimide (PI) substrate. The resulting LIG-S, plastic shavings by laser, exhibits sufficient mechanical and electrical properties to enable many applications including strain-tolerant spring electrodes, antennas, supercapacitors, gas sensors, and luminescent filaments under extreme conditions. Without using any conventional fabrication techniques or other labor-intensive, time-consuming, and expensive processes, this novel approach enables a high-throughput mass production of macro-, micro-, and nanoscale featured LIG-S that can be manufactured within seconds to realize many open opportunities in all-carbon electromechanical systems.

Effects of vertical coil springs on the performance of solar air heaters: Experimental study

Using extended surfaces or turbulators on the absorber plate (AP) is one of the great ways to enhance the thermal performance of solar air heaters (SAHs). Although a large number of studies have been conducted in this field, new geometries are still being proposed to improve the tradeoff between heat transfer enhancement and corresponding blowing power penalty. Coil springs are new offerings as turbulators, and the scientific literature currently lacks a parametric study to address the benefits of using such extended surfaces. To cover this gap, an experimental analysis of the AP equipped with vertical coil springs is carried out. The effects of different geometrical factors (coil height, coil pitch, coil diameter, and wire diameter) at three different levels are investigated for Reynolds number ranging from 5867 to 23471. One of the most important findings of this research is that, unlike most other turbulators, the heat transfer enhancement obtained using CSs is often greater than the resulting pressure drop. Therefore, the overall performance index is found to be always higher than unity, reaching a maximum value of 2.98 for the case with a coil diameter of 10 mm at Re = 5867. It is worth mentioning that upon varying the coil height from 3 mm to 9 mm, the highest Nusselt number and best overall performance are achieved at 6 mm. It is found that the overall performance of SAH declines by increasing both the coil pitch and the coil diameter. Comprehensive correlations are developed considering the effects of all geometrical parameters. The results predicted by the correlations match well with the experimental data with average errors within ± 10%.

Ekspresi BMP2 dan TRAF6 pada Jaringan Periodontal setelah Pemberian Ekstrak Kopi Robusta selama Pergerakan Gigi Ortodonti

Orthodontic tooth movement occurs due to mechanical stimulation followed by alveolar bone and periodontal ligament remodeling. Bone remodeling is the process of bone resorption in areas of tension and bone formation in areas of tension. Various techniques and drugs are used to speed up orthodontic treatment. This study aims to analyze the expression of BMP2 and TRAP6 on orthodontic tooth movement after the administration of Robusta coffee extract. Twenty-four Wistar rats were divided into 4 groups: C1 (2 weeks) and C2 (3 weeks) groups: rats were given orthodontic mechanical force (OMF) and T1 (2 weeks) and T2 (3 weeks) groups rats were given OMF and Robusta coffee extract. OMF in rats was performed by moving the maxillary right permanent molars mesially with a Niti closed coil spring. Observations were made on the 15th and 22nd day by immunohistochemical examination to determine the expression of BMP2 and TRAP6. Administration of Robusta coffee extract for 2 weeks and 3 weeks increased BMP2 and TRAP6 expression (p <0.05). Administration of Robusta coffee extract increased the expression of BMP2 and TRAP6 in the alveolar bone during orthodontic tooth movement.

Bevacizumab, a vascular endothelial growth factor inhibitor, promotes orthodontic tooth movement in an experimental rat model

ObjectiveThis study aimed to evaluate the impact of bevacizumab on orthodontic tooth movement (OTM) in Wistar rats. Materials and methodsThe OTM model was constructed by placing an orthodontic coil spring between the maxillary first molar and anterior tooth. Bevacizumab (Avastin®; 10 mg/kg twice per week) was started one week before the OTM and continued for 3 weeks. After 1 and 2 weeks, OTM distance and anterior tooth mobility were measured. Thereafter, the maxilla was dissected for micro-CT microarchitectural analysis, followed by histological analysis, and tartrate-resistant acid phosphatase (TRAP) staining. Moreover, the distributions of collagen fibers type-I and –III (Col-I and Col-III) were evaluated using Picro-Sirius red staining. ResultsOrthodontic force prompted bone resorption and formation on the pressure and tension sides, respectively. Bevacizumab therapy resulted in a 42% increase of OTM, particularly after 2 weeks. Furthermore, bevacizumab disturbed the morphometric structure at both pressure and tension sites. The histological evaluation indicated about 35–44% fewer osteoblasts in the bevacizumab group, especially at the tension side, whereas the proportion of TRAP-positive osteoclasts at the pressure side was 34–37% higher than the control. The mature Col-I was reduced at the tension site by 33%, whereas the Col-III/Col-I ratio was enhanced by 20–44% at pressure and tension sites, after 2 weeks, in the bevacizumab group. ConclusionAnti-vascular bevacizumab therapy accentuates OTM in rat model, possibly through the enhancement of bone resorption, at the pressure side, and the reduction of bone formation, at the tension side as well as dysregulation of collagen fibers distribution.

Fabrication ofShearing‐Motion‐TypeTactile Display Mechanism UsingSMA Thick‐FilmActuators and Coil Springs Array

AbstractA shearing‐motion‐type microelectromechanical system (MEMS) tactile display mechanism was fabricated to provide a shear vibration stimulus to the fingertip. It consisted of shrinking shape memory alloy (SMA) thick‐film actuators and a supporting coil spring array. The SMA actuator array was designed and fabricated using a flash‐evaporated SMA film (10 μm thick) on a mirror‐polished Cu substrate. The coil spring was successfully arrayed on a glass substrate with an SU‐8 circular array pattern. The glass substrate with the coils was bonded to the SMA substrate to complete the shearing‐motion mechanism. During the bonding process, the SMA actuators were initially elongated by the coil springs. The generated amplitude and force of the fabricated mechanism were characterized when the SMA actuator was heated by applying a pulsed current to be shrank by the shape recovery effect. The fabricated shearing‐motion mechanism successfully generated large amplitude of 41 μm (around 80 μm in reciprocal motion) and force of 22 mN at a driving frequency of 1 Hz. At 20 Hz, an amplitude of 23 μm and force of 10 mN were obtained even though they were reduced owing to the low thermal response. At both driving frequencies, the obtained amplitudes and forces seems to be sufficient for tactile stimulation to finger skin. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC.

Fatigue Properties of Spring Steels after Advanced Processing.

This article deals with the effect of strain-assisted tempering (SAT) on the fatigue properties of 54SiCr6 steel used for spring steel wires in a wide variety of automotive applications, including coil springs. This steel spring wire is extremely strong, having a high elastic limit and yield point, giving the steel excellent energy accumulation and fatigue properties. This combination opens up new possibilities in helical and cylindrical coil spring design, resulting in the reduction of both size and weight. Lightweight coil springs lead to improvements in fuel consumption, stability and vehicle traction. A large plastic deformation and SAT were applied to enhance the yield point of the study material. Improvements in the static and cyclic properties of steel springs were investigated using tensile tests and 3PB fatigue tests at ambient temperature. In addition, an advanced laser shock peening (LSP) process was employed to increase the fatigue resistance of the SAT material. The results presented here show great improvements in the static and fatigue properties over commercial steel treatment. The material quality of the wires was evaluated to be insufficient for further processing with cold coiling.

Finite element analysis of tooth movement under different retraction force and intrusive force in double-archwire lingual orthodontics system

The objectives of this study were to evaluate the tooth movement tendency during space closure in maxillary anterior teeth by various combinations of retraction force and intrusive force in a double-archwire lingual orthodontic system. Mini-implant-double slot lingual orthodontics system models of the bilateral maxillary first premolar extraction cases were constructed. Three-dimensional finite element models of the maxilla were constructed with definite position mini-implants (8 mm) and power arms (6 mm). Different retraction forces(50gf、100gf、150gf)were applied with the help of a nickel-titanium closed coil spring on the plate side. Intrusive forces(0gf、50gf、100gf)were applied with the help of the mini-implant between the two central incisors, and the initial displacements of the maxillary anterior teeth were analyzed. Variable amounts of displacements like controlled tipping, uncontrolled tipping, lingual crown tipping, labial root tipping, extrusion and distal crown tipping were observed in all the models, and these tendencies increased as the magnitude of retraction force increased, and these tendencies decreased as the magnitude of intrusive force increased. When the intrusive force was greater than or equal to the retraction force, the maxillary central incisors showed the trend of lingual crown tipping and labial root tipping, resulting in uncontrolled tipping movement. In terms of horizontal changes, the increasing width of bilateral anterior teeth was observed, with canines showing the least increasing trend. Various combinations of retraction force and intrusive force in a double-archwire lingual orthodontic system provide a new choice for torque control of the anterior teeth. Although anterior mini-implants and elastics can achieve incisor intrusion and lingual root torque, they cannot achieve the expected torque without additional torque control methods.

Control Mass-Spring-Damper Based on Tuning Trade-off PID Controller

This paper discusses control mass-spring-dumper (MSD) system used in vehicle suspensions. The vehicle suspension consists of mass, coil (spring), and shock absorber (dumper). MSD provided a shock effect when the vehicle was caused by the frictional force on the load. The dificulty to achive the stability of suspension and the following of set point tracking. Therefore, the proportional-integral-derivative (PID) based on tuning 1-degree of freedom (1-DOF) and 2-degree of freedom (2-DOF) were proposed to stability when the disturbance accours. The MSD equation was obtained by using the laplace transform and validated in Matlab Simulink. The result shows that the proposed PID control reduces disturbance rejection by the smaller set point tracking peak amplitude of 0.01, overshoot of 0.68%, rise time of 0.199 seconds. The 1-DOF tuning achieved set point tracking and disturbance rejection with a peak amplitude of 1.13, overshoot 12.9%, rise time 0.134 seconds, and the 2-DOF tuning achived set point tracking and disturbance rejection with peak amplitude of 1.07, overshoot 6.53%, rise time 1.28 seconds. The proposed PID control has the best performance than 1-DOF and 2-DOF controller.

Effect of local application of bone morphogenetic protein -2 on experimental tooth movement and biological remodeling in rats.

Background: This study attempts to detect the potential effects of local bone morphogenetic protein -2 (BMP-2) on orthodontic tooth movement and periodontal tissue remodeling. Methods: Forty adult SD rats were randomly divided into four groups: blank control group, unilateral injection of BMP-2 on the pressure side or tension side of orthodontic teeth and bilateral injection of BMP-2. Their maxillary first molar was moved by a 30g constant force closed coil spring. 60μL of BMP-2 with a concentration of 0.5μg/mL was injected into each part at a time. In addition, three rats were selected as healthy control rats without any intervention. Fluorescent labeled BMP-2 was used to observe the distribution of exogenous BMP-2 in tissues. Micro-CT was used to measure the microscopic parameters of tooth displacement, trabecular bone and root absorption volume. Three different histological methods were used to observe the changes of tissue remodeling, and then the number of osteoclasts and the content of collagen fibers were calculated. Results: Compared with the blank control group, BMP-2 injection reduced the movement distance and increased the collagen fiber content and bone mass (p < 0.01). There was no significant difference in tooth movement distance, BV/TV ratio and BMD between injection sites in unilateral injection group (p > 0.05). In the case of bilateral injection of BMP-2, the osteogenesis is enhanced. Unilateral injection of BMP-2 did not promote root resorption, but double injection showed root resorption (p < 0.01). Conclusion: Our study does show that the osteogenesis of BMP-2 is dose-dependent rather than site-dependent when a certain amount of BMP-2 is applied around orthodontic teeth. Local application of BMP-2 around orthodontic teeth in an appropriate way can enhance bone mass and tooth anchorage without increasing the risk of root absorption volume. However, high levels of BMP-2 may cause aggressive root resorption. These findings are of great significance, that is, BMP-2 is an effective target for regulating orthodontic tooth movement.

Non-Surgical Camouflage Treatment of a Skeletal Class III Patient with Anterior Open Bite and Asymmetry Using Orthodontic Miniscrews and Intermaxillary Elastics

This case report presents the non-surgical orthodontic camouflage treatment of an 18-year-old male patient with skeletal Class III asymmetry and severe anterior open bite. The anterior open bite was corrected by extrusion of the maxillary and mandibular anterior teeth and clockwise and counterclockwise rotation of the maxillary and mandibular occlusal plane, respectively, using intermaxillary Class III elastics between the maxillary posterior buccal miniscrews and mandibular canines and anterior vertical elastics between the maxillary and mandibular canines. Class III dental relationships and dental asymmetry were corrected via unilateral distalization of the mandibular dentition on the left side using a closed coil spring between the buccal shelf screw and hook. The patient’s smile esthetics and dental relationship were improved with a more favorable facial profile, and facial asymmetry was slightly alleviated after orthodontic camouflage treatment. The total treatment time was 15 months. A modified wraparound retainer with a scalloped labial bow, tongue crib, and tooth positioner was used simultaneously to prevent the potential relapse.

Design and experimental study of a two-stage nonlinear vibration isolators with quasi-zero stiffness

Quasi-zero-stiffness (QZS) vibration isolators are practical solutions for isolation in the low-frequency range. However, single-layer QZS isolators have a low roll-off rate of transmissibility in the frequency band of isolation, especially at high frequencies. The purpose of this study is to design a novel two-stage QZS isolator, called TSQZS isolator. In each stage, the quasi-zero stiffness is achieved by combining magnetic rings and linear springs in parallel. The TSQZS isolator can support a wide range of payloads by adjusting the initial compression of the positive-stiffness element (coil spring). Firstly, an analytical model of magnetic spring is given by employing the theory of equivalent magnetic charge, and the parameters are designed using the finite element simulation. Then, the dynamic behaviors of the TSQZS isolation system are revealed by using the harmonic balance method, and the isolation performance is assessed by displacement transmissibility. Finally, an experimental prototype is fabricated and the experimental testing setup is established to verify the isolation performance of the TSQZS system under base excitation. The results demonstrate that the devised TSQZS isolator not only enables vibration isolation at low frequencies, but also gains a high roll-off rate of transmissibility in the frequency band of vibration isolation.

Comparative Evaluation of Effect of Micro-Osteoperforation and Mechanical Vibration on Rate of Orthodontic Tooth Movement in Young Adults With Bimaxillary Protrusion.

To evaluate and compare the rate of orthodontic tooth movement and root resorption by micro-osteoperforation (MOP) and mechanical vibration in young adults with bimaxillary protrusion. Twenty patients having class I bimaxillary protrusion who required all first premolar extraction were allocated into two groups MOP (Group A) and mechanical vibration (Group B), with a 1:1 allocation ratio. After leveling alignment MOP was performed on either side of the arch, and vibration was applied on the contralateral side 20 mins per day. Canines were retracted with nickel-titanium coil springs, and Alginate impressions were taken every four weeks till 4 months. The mean rate of retraction of canines of Group A was more than Group B. There was a statistically significant difference between Group A and Group B. (p=0.0120) Conclusion: The mean rate of retraction of canines treated by MOP was 1.15 mm per 4 weeks, and by mechanical vibration, 0.8mm per 4 weeks.

Fatigue Life Modelling of Steel Suspension Coil Springs Based on Wavelet Vibration Features Using Neuro-Fuzzy Methods

This study proposed wavelet-based approaches to characterise random vibration road excitations for durability prediction of coil springs. Conventional strain-life approaches require long computational time, while the accuracy of the vibration fatigue methods is unsatisfactory. It is therefore a necessity to establish an accurate fatigue life prediction model based on vibrational features. Wavelet-based methods were applied to determine the low-frequency energy and multifractality of road excitations. Strain-life models were applied for fatigue life evaluation from strain histories. ANFIS modelling was subsequently adopted to associate the vibration features with the fatigue life of coil springs. Results showed that the proposed wavelet-based methods were effective to determine the signal energy and multifractality of vibration signals. The established vibration-based models showed good fatigue life conservativity with a data survivability of more than 90%. The highest Pearson coefficient of 0.955 associated with the lowest RMSE of 0.660 was obtained by the Morrow-based model. It is suggested that the low-frequency energy and multifractality of the vibration signals can be used as fatigue-related features in life predictions of coil springs under random loading. Finally, the proposed model is an acceptable fatigue life prediction method based on vibration features, and it can reduce the dependency on strain data measurement.