# Research on Bifurcated Origami Hydraulic Dampers for Real Road Vibration Loads
## 4 Conclusions and Future Work  
This study introduced a design for a bifurcated origami hydraulic damper. The following conclusions were drawn from theoretical analyses and validation experiments:  
1. Through analysis of the mechanical characteristics and derivation of a new damping force formula, it was demonstrated that the damping force of the bifurcated origami hydraulic damper is directly proportional to the square of the velocity of motion;
2. A vibration test apparatus incorporating a bifurcated origami hydraulic damper was developed. Summarizing the main components--mass block as the damping object, elastic spring device, bifurcated origami hydraulic damper, and friction-induced damping elements--we established control equations for nonlinear motion and proposed a numerical analysis approach using the Runge-Kutta method. Numerical results aligned well with actual experimental measurements;
3. Vibration experiments were conducted using random vibration waves recorded on a gravel road. Results showed that damping effectiveness was nearly halved when oil was injected into the bifurcated origami hydraulic damper compared with conditions without oil injection, underscoring the significant vibration-damping capability of the damper;
4. The impact of orifice hole diameter, a critical design parameter of the bifurcated origami hydraulic damper, on damping performance was investigated experimentally. Collision-damping effectiveness decreased as the orifice hole diameter increased;
5. Validation experiments examined the influence of hydraulic oil type and temperature within the bifurcated origami hydraulic damper. The effects of oil type and temperature on damping effectiveness were found to be 5.99% and 4.25%, respectively, indicating a relatively minor impact on collision-damping performance;
6. The response acceleration values of the mass blocks were measured using a three-dimensional accelerometer under asymmetric vibration with off-center loads. It was observed that the standard deviation of the response acceleration values was reduced by 53.44% compared with those without oil injection. This finding highlights the effectiveness of the bifurcated origami hydraulic damper in managing vibrations in complex environments.  
The bifurcated origami structure damper proposed in this paper allows for better adjustment of the origami posture according to specific load directions compared with conventional hydraulic dampers. Additionally, due to its unique characteristics, the oil inside the main origami damper can be discharged through pipes to the oil origami tank placed in a less constrained area, thereby enhancing space utilization efficiency. These dampers do not require complex mechanical connection structures, offering significant advantages in lightweight and compact spaces.  
However, due to the bifurcated origami hydraulic damper constructed with a thin origami structure, it is difficult to apply to large loads such as heavy trucks. Future research should focus on improving the performance of bifurcated origami hydraulic dampers and on promoting further research on their practical applications in automobile suspensions and other areas.  
Writing--original draft preparation, J.G.; writing--review and editing, J.G. and X.Z.; data curation, B.Z.; investigation, Y.L.; software, W.Z.; conceptualization, W.Z. and X.Z.; methodology, J.G. and B.Z.; validation, Y.L. All authors have read and agreed to the published version of the manuscript.  
This research received no external funding.  
Not applicable.  
The data are available in a publicly accessible repository.  
The authors declare no conflicts of interest.