Surface Finish Enhancement in a Turning Operation via Adaptive STR Control of the Depth of Cut

2003 ◽  
Vol 125 (2) ◽  
pp. 289-296 ◽  
Author(s):  
E. Liasi ◽  
W. P. T. North
Keyword(s):  
Adaptive Control ◽  
Control System ◽  
Surface Finish ◽  
Radial Direction ◽  
Depth Of Cut ◽  
Micro Hardness ◽  
Turning Process ◽  
Radial Vibrations ◽  
Self Tuning

In this paper, an integrated model for a turning process (in the radial direction) is presented. Furthermore, properties of adaptive control and more specifically self-tuning regulators (STR) are discussed and a self-tuning regulator is designed based on LQG methods. The objective is to suppress the radial vibrations due to surface micro-hardness variations and hence improve the resulting surface finish. The effectiveness of the control system is evaluated by means of computer simulations—a case study is presented.

OPTIMISING CUTTING PARAMETERS FOR HOT TURNING ON EN31 MATERIAL

2021 ◽  
Vol 5 (10) ◽  
Author(s):  
Prof. Hemant k. Baitule ◽  
Satish Rahangdale ◽  
Vaibhav Kamane ◽  
Saurabh Yende
Keyword(s):  
Surface Roughness ◽  
Surface Finish ◽  
Cutting Speed ◽  
Cutting Parameters ◽  
Machining Process ◽  
Depth Of Cut ◽  
Multiple Time ◽  
Turning Process ◽  
Workpiece Material ◽  
Hot Turning

In any type of machining process the surface roughness plays an important role. In these the product is judge on the basis of their (surface roughness) surface finish. In machining process there are four main cutting parameter i.e. cutting speed, feed rate, depth of cut, spindle speed. For obtaining good surface finish, we can use the hot turning process. In hot turning process we heat the workpiece material and perform turning process multiple time and obtain the reading. The taguchi method is design to perform an experiment and L18 experiment were performed. The result is analyzed by using the analysis of variance (ANOVA) method. The result Obtain by this method may be useful for many other researchers.

A Control System to Improve the Accuracy of Finished Surfaces in Milling

1983 ◽  
Vol 105 (3) ◽  
pp. 192-199 ◽  
Author(s):  
T. Watanabe ◽  
S. Iwai
Keyword(s):  
Adaptive Control ◽  
Control System ◽  
Tool Path ◽  
Numerical Control ◽  
Depth Of Cut ◽  
Bending Moments ◽  
Adaptive Control System ◽  
Location Error ◽  
Milling Operations ◽  
Finished Surface

Adaptive control to keep the accuracy of the shape of a workpiece within acceptable levels by altering the numerical control commands according to variations of manufacturing process parameters is called “geometric adaptive control.” In this paper, a geometric adaptive control system to compensate for errors in the finished surface due to tool deflection generated by milling operations is presented. The effects of cutting forces upon the shape of the finished surface are analyzed, and the composition of the system is discussed. In the system, the location error and the waviness error at the finished surface are evaluated from the sensed bending moments in the tool. These two errors are compensated for by shifting the tool path and by adjusting the feedrate, respectively. It is verified by experiments that the accuracy of the finished surface is improved significantly by using the system described in cases where the depth of cut varies. Geometric adaptive control is useful even when a workpiece is machined by both rough and finish cuts.

Experimental Study on Surface Integrity, Dimensional Accuracy, and Micro-Hardness in Thin-Wall Machining of Aluminum Alloy

2018 ◽  
Vol 5 (2) ◽  
pp. 13-31
Author(s):  
Gururaj Bolar ◽  
Shrikrishna N. Joshi
Keyword(s):  
Aluminum Alloy ◽  
Process Parameters ◽  
Surface Finish ◽  
Dimensional Accuracy ◽  
Depth Of Cut ◽  
Thin Wall ◽  
Micro Hardness ◽  
Wall Deflection ◽  
High Feed ◽  
Axial Depth

This article presents an experimental investigation into the influence of process parameters viz. feed per tooth, axial depth of cut on milling force, surface finish, wall deflection and micro-hardness during thin-wall machining of an aerospace grade aluminum alloy 2024-T351. Results revealed that the process parameters significantly influence the surface finish and dimensional accuracy of machined thin-walls. High feed rate promoted the formation of built-up-edge (BUE). Combination of high feed and axial depth of cut aided in catastrophic failure of tools. Surface damages such as material plucking, material shearing, material adhesion and deformed feed mark layer formation were observed. Axial depth of cut negatively influenced the wall deflection leading to loss of dimensional accuracy. Interestingly, the micro-hardness at the machined surface was found to be lower than that of the bulk material hardness. These results will be useful in selection of suitable process parameters for quality and precise machining of thin-wall parts.

Study of the Cutting Parameters on Surface Roughness and Material Removal Rate in Hard Turning of UHMWPE

2020 ◽  
Author(s):  
César Oswaldo Aguilera-Ojeda ◽  
Alberto Saldaña-Robles ◽  
Agustín Vidal-Lesso ◽  
Israel Martínez-Ramírez ◽  
Eduardo Aguilera-Gómez
Keyword(s):  
Surface Roughness ◽  
Predictive Model ◽  
Material Removal Rate ◽  
Surface Finish ◽  
Material Removal ◽  
Removal Rate ◽  
Cutting Parameters ◽  
Depth Of Cut ◽  
Feed Speed ◽  
Turning Process

Abstract The surface finish of industrial components has an important role in their performance and lifetime. Therefore, it is crucial to find the cutting parameters that provide the best surface finish. In this work, an experimental study of the effect of cutting parameters on ultra-high molecular weight polyethylene (UHMWPE) by a turning process was carried out. Today, the UHMWPE polymer continues to find applications mainly in the automotive industry and biomechanics because it is resistant to impact and corrosive materials to use. A face-centered Central Composite Design (CCD) and Response Surface Methodology (RSM) were applied to evaluate the influence of the cutting speed (Vc), feed rate (f) and depth of cut (ap) of the turning operation on the Average Surface Roughness (Ra) and Material Removal Rate (MRR). Results allowed obtaining an adjusted multivariable regression model that describes the behavior of the Ra that depends on the cutting parameters in the turning process. The predictive model of Ra showed that it fits well with a correlation coefficient (R2) around 0.9683 to the experimental data for Ra. The ANOVA results for Ra showed that the feed is the most significant factor with a contribution of 42.3 % for the term f 2, while the speed and depth of cut do not affect Ra with contributions of 0.19% and 0.18%, respectively. A reduction of feed from 0.30 to 0.18 mm·rev−1 produces a decrease in surface roughness from 6.68 to 3.81 μm. However, if the feed continued to reduce an increase in surface roughness, a feed of 0.05 mm·rev−1 induces a surface roughness of 14.93 μm. Feeds less than 0.18 mm·rev−1 cause a heat generation during turning that increases the temperature in the process zone, producing surface roughness damage of the UHMWPE polymer. Also, the results for MRR demonstrated that all of the cutting parameters are significant with contributions of 31.4%, 27.4% and 15.4% to feed, speed, and depth of cut, respectively. The desirability function allowed optimizing the cutting parameters (Vc = 250 m·min−1, ap = 1.5 mm y f = 0.27 mm·rev−1) to obtain a minimum surface roughness (Ra = 4.3 μm) with a maximum material removal rate (MMR = 97.1 cm3·min−1). Finally, the predictive model of Ra can be used in the industry to obtain predictions on the experimental range analyzed, reducing the surface roughness and the manufacturing time of UHMWPE cylindrical components.

Reduced order indirect self-tuning regulator for a novel pneumatic tele-operation system

2019 ◽  
Vol 234 (3) ◽  
pp. 370-383
Author(s):  
Mohamad Baayoun ◽  
Naseem Daher ◽  
Matthias Liermann
Keyword(s):  
Adaptive Control ◽  
Control System ◽  
Force Feedback ◽  
Adaptive Controller ◽  
Adaptive Control System ◽  
Bilateral Control ◽  
Active Components ◽  
Operation System ◽  
Reduced Order ◽  
Self Tuning

This article presents a reduced order indirect self-tuning regulator for a passive pneumatic tele-operation system, which is intended for use in medical surgeries in magnetic resonance imaging environments with short transmission distances ([Formula: see text]), where force feedback is required. The novel tele-operation system uses less active components as compared to conventional systems and realizes a bilateral control without the use of a force or pressure sensor. The proposed adaptive control system is validated in simulation and experimentation on a test rig built for this purpose. Special attention is given to the notion of transparency of the system, which is the ratio between the resistance of the master device experienced by the operator and the actual resistance of the remote environment in contact with the slave device. The adaptive controller shows advantage over a previously designed non-adaptive control system design in terms of stiffness, damping, and transparency.

Sign in / Sign up

Export Citation Format

Share Document