Design and Development of Class 2B-lpl Compliant Constant-Force Compression Slider Mechanism

Abstract

This research work focuses on the design and development of Class 2B-lpl compliant constant-force compression slider mechanism. It also expresses the desire to simplify the behavioral model for easy usage. Results obtained indicated an average non-dimesionalized parameter value of 1.2573, 1.2991, 1.3483, and 1.4081 for a 10, 20, 30, and 40% displacement respectively. The result also shows that the average force generated by the mechanism for a 10, 20, 30, and 40% displacement were 901.23N, 316.56N, 171.17N, and 110.44N respectively using the maximum flexible segments parameter values for the different percentages of mechanism slider displacement. This indicates clearly that using the non-dimensionalized parameter, the average force generated by this class of mechanism can easily be determined which greatly simplifies its usage.

Development of Modified Constantforce Compression Slider Mechanisms

“…1 shows the side-by-side comparison of the modified constant-force CSMs with the original constant-force CSMs. These mechanisms have been divided into 5 classifications based on the number of flexible segments and their location in each CSMs [12,16]. As shown in Fig.…”

“…1 is denoted by a string of letters representing the order and type of pivots used. The letters "s", "l", "p", and "m" represents small-length flexural pivot, long flexible beam, pin joint, and modified respectively [12]. The generalized PRBM for all the modified CSMs presented in Fig.…”

“…Each of the modified CSMs presented in Fig. 1 can be converted to its equivalent rigid-body counterpart by using the PRBM rule for small-length flexural pivots, the PRBM rule for modified long fixed-pinned flexible beams, the PRBM rule for modified long fixed-fixed flexible beams, or a combination of the PRBM rules [12]. The most straightforward alteration is that every flexible segment becomes two rigid segments joined by a pin and torsional spring [1; 6; 12; 13; 14;15; 16].…”

“…The definition in Fig. 3, together with those tabulated in Table 3, may be used to determine the length of the flexible and rigid segments for all modified CSMs investigated [15]. Using Lagrange's method of formulation, taking θ 2 as the generalized position coordinate, and neglecting the effect of damping on the modified CSM model, Lagrange's equation for a static system may be expressed as [11;12; 13; 14] δ(V) δθ 2…”

“…and C 3 are the coulomb friction coefficients at the different pivot points, usually obtained from the experiment. The value of the torque τ AF may be approximated using the following expression [12]…”