The Electric Bicycle Rear Suspension Mechanism Optimization Design Based On Force Ratio Curve

As price of the fossil fuel rising up and the deterioration of the environment, electricbicycles gradually become a main means of transportation for people to go out. With theadvantage of zero emissions, low noise, low energy consumption, low failure rate and cost,high-speed, environmental protection, Electric bike progressively become the upgradedproducts for motorcycle.Electric bicycle rear suspension mechanism is the main shockabsorbing structure and is an important component to improve the riders’ comfort. Currently,electric bike rear suspension mechanism is four-bar linkage and six-bar linkage. The former issimple and easy to design and install. The later is relatively complex, but the force ratio isrelatively much higher. This paper proposes a optimization design method based on the forceratio curve, which can substantial increase in the force ration of six bar linkage ratio, thusraising the rear suspension shock absorption of shock absorption ability. In this paper, themain content is as follows:（1）classified and summarized the existing electric bicycle frame structure andsuspension system.（2）simply introduced the method and theory of plane mechanism motion analysis,lay the theoretical basis for the force curve derivation in next chapter.（3）derived the force ration formula in a six-bar linkage suspension electric bicycleand drew its curve, and analyzed its main influencing factors.（4）Used the genetic algorithm to optimize the force ratio curve and got a new set ofdata of six-bar linkage; Then build the model according to the optimized suspension size in the ADAMS software, and to verify the calculation results and the simulation results. Theresults showed that the maximum error is2.3%and the minimum error is0.04%. And theresults also proved the reasonableness of the force curve method.