Bicycle Front Linkage Suspension

Last crawled date: 3 years, 1 month ago

The present suspension assembly for bicycle may be summarised as the linkage assembly comprising fork, lower arms, intermediate arm, upper arm and shock absorber. The lower arm is pivotally secured to the coupler attached at the lower end of the fork. The upper arm is pivotally secured to the front fork. The intermediate arm being pivotally connected to the other ends of the lower arms and upper arm. The axle of the front wheel is inserted through the intermediate link eye and through the wheel hub, clamped in the journal. One eye of the shock damper is secured pivotally to the upper arm and the other eye is connected pivotally to the fork stem. Sex bolts and barrel nuts are used for pivoting the arms and shock absorber. However, any other barrel fasteners could be used. The anchors of the shock dampers are designed in a way that it secure itself in the slot and experiences minimum friction. The shock absorber wherein the upper pivoting bracket was optimized by providing holes. The FEA was performed to ensure the optimization. The lower arm, intermediate arm and upper arm are optimized by providing pockets in an attempt to reduce the material and make a sturdy suspension assembly. (Please find the attached 2D drafting for the same)
When the bicycle front wheel hits a bump, the front wheel tends to move up and down. This upward and downward movement of the wheel causes the swinging of the lower and upper arm, tends the intermediate arm to swing about the fork. The swinging movement of the upper arm about the pivot hence causes the coil spring of shock absorber to compress, absorbing the shocks and forces thereby. The transient analysis (FEA) was performed to simulate the same and results obtained could be seen in attached video and photos. The displacement was applied to the journal where the wheel axle is intended to be clamped. The displacement coordinates were found out using CATIA interface. It can be seen the stresses are acting in the coil spring on movement of the intermediate arm.
Being a Mechanical Engineering student, this was a small attempt to showcase my engineering, modelling and simulation skills.
Hope you guys like it :)