Profile Determination of Planar and Spatial Cams with Cylindrical Roller-Followers

Tsay, Der-Min; Lin, Bor-Jeng

doi:10.1243/pime_proc_1996_210_231_02

Cited by 13 publications

(13 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this article, the globoidal cam profile is determined by using the volume swept method [14]. As the motion curve of roller's centre is the same as that of the output axis, the position of centre can be determined from the known conditions of the output motion.…”

Section: Determining Globoidal Cam Profile By Using the Volume Swept Methodsmentioning

confidence: 99%

Motion-curve synthesis and geometric design of globoidal cam mechanism with intermittent variable speed

Lin

LIN

Jywe

et al. 2007

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

A design procedure for increasing the performance of an intermittent globoidal cam mechanism is presented. The proposed procedure is based on the synthesis of roller-follower turret motions at two different speeds to lower the inertia effect caused by the start/stop behaviour of the intermittent mechanism. The motion curves in a globoidal cam mechanism with an intermittent variable speed are defined by non-parametric rational B-splines to increase the transport capability. There are four key techniques to design a cam mechanism: the first is to construct the cam profile by using the volume swept method, the second is to synthesize the motion curve of a turret by using a rational B-spline curve on velocity control, the third is to analyse the mechanical properties of cam by using the geometrical vector method, and the last is to plan an NC programme and to estimate the performance of five-axial precision machining. Four types of motion curves with similar geometric properties are used and the rational B-spline has better dynamic properties than the other three curves. The systematic design approach proposed for a globoidal cam mechanism with an intermittent variable speed is to improve its performance, to upgrade effectively the function of the indexing device, and to increase the production speed of industrial automatic conveyance.

show abstract

Section: Determining Globoidal Cam Profile By Using the Volume Swept Methodsmentioning

confidence: 99%

Motion-curve synthesis and geometric design of globoidal cam mechanism with intermittent variable speed

Lin

LIN

Jywe

et al. 2007

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

show abstract

“…To realize a non-linear spring characteristic, we adapt the cam mechanism used in [23]. The shape of the cam is computed using the method in [24]. To smoothen the cam design, the spring characteristic is divided between two parts of the cam surfaces, each followed by a different follower.…”

Section: B Notes Towards Realizationmentioning

confidence: 99%

Unparameterized Optimization of the Spring Characteristic of Parallel Elastic Actuators

Spaa

Wolfslag

Wisse

2019

IEEE Robot. Autom. Lett.

View full text Add to dashboard Cite

In electrically actuated robots most energy losses are due to the heating of the actuators. This energy loss can be greatly reduced with parallel elastic actuators, by optimizing the elastic element such that it delivers most of the required torques. Previously used optimization methods relied on parameterizing the spring characteristic, thereby limiting the set of spring characteristics optimized over and with that the loss reduction that can be obtained. This paper shows that such parametrization is not necessary; a method is presented to compute the optimal characteristic as an analytic function of the trajectory. The efficacy of this method is demonstrated using two examples. The first example considers the optimal spring characteristic for a parallel elastic actuator supporting the human ankle during walking. The second example applies the method in combination with trajectory optimization on a single degree of freedom robot performing a specific pick-andplace task. The task at hand has a height difference between the pick and the place location. With the analytical optimal spring, it is shown that the robot can recover enough of the energy released by the package to function without external electric energy supply.

show abstract

“…In order to realize the eOE ects of geometric diOE erences between an ideal cam± turret system and a real one on its output, the theoretical cam surfaces that serve as fundamentals of this investigation must ® rst be described. A procedure based on the rigid body transformation method can readily be used to de® ne the cam pitch surface [10]. As Figs 2 to 4 illustrate, the cam surfaces can be represented as the swept surfaces of the tool path.…”

Section: Tool Path and Cam Pitch Surfacementioning

confidence: 99%

“…To obtain analytical pro® le formulations and to analyse conditions of undercutting of planar and spatial cams, two main procedures based on the screw theory [7] and the theory of envelopes [8,9] have been successfully developed. Recently, without considering clearances in globoidal grooved cams, Tsay and Lin [10] showed a simple yet eOE ective approach utilizing the rigid body transformation technique to generate cam surface coordinates that can be further used to derive principal curvatures, contact forces and torques between a globoidal cam and its roller-follower turret.…”

Section: Introductionmentioning

confidence: 99%

Consideration of manufacturing parameters in the design of grooved globoidal cam indexing mechanisms

Tsay

2001

Proceedings of the Institution of Mechanical Engineers, Part C:

Self Cite

View full text Add to dashboard Cite

By considering the manufacturing variables involved in the processes of machining and assembly, analytical expressions for the turret motion and indexing accuracy of intermittent grooved globoidal cam mechanisms have been identified. Based on the kinematic and geometric relationships between the cam and its roller-follower turret, the effects on the output of the cam mechanism owing to clearances in the grooved cam and in the roller bearing, preload between the cam and its turret wheel and the cam taper angle have been investigated. As a result, the roller alternation in the cam-turret system has been analysed. Favourable parameters for the design, machining and assembly can be selected to manufacture such devices with improved turret motion and indexing accuracy. Worked examples are given to demonstrate the usefulness and effectiveness of the approach.

show abstract

Profile Determination of Planar and Spatial Cams with Cylindrical Roller-Followers

Cited by 13 publications

References 6 publications

Motion-curve synthesis and geometric design of globoidal cam mechanism with intermittent variable speed

Motion-curve synthesis and geometric design of globoidal cam mechanism with intermittent variable speed

Unparameterized Optimization of the Spring Characteristic of Parallel Elastic Actuators

Consideration of manufacturing parameters in the design of grooved globoidal cam indexing mechanisms

Contact Info

Product

Resources

About