Offer of Research Topics

Offer from	University	Keio University
	Faculty / Department	Faculty of Science and Technology, Mechanical Engineering Department
	Group Name	Mitsui Laboratory
Research Theme		Estimation of Error Parameters in the Measuring Apparatus for Motion Accuracy of NC Machine Tools
Brief Explanation		A number of dynamic motion accuracy measuring methods for NC machine tools have been proposed, including the commonly-used DBB (Double Ball Bar) method. However, the common drawback to many tool path measuring methods such as DBB method is a short measuring range and measurements along arbitrary tool path in a three dimensional space is not possible. An instrument capable of measuring arbitrary dynamic NC tool path in three-dimensional space has been developed. The instrument has three rotating axes connected with two serial links. Three rotary encoders measure the rotational motion of the axes. The measuring instrument includes errors, for example link lengths and positional errors between the rotational axes of the links. To achieve higher measuring accuracy, it is necessary to identify these error parameters precisely, and then the error parameters must be used in the transformation equations. In this study, several kinds of nonlinear least square methods will be applied to identify error parameters.
Research Steps		1. Literature survey 1 month 2. Experiment 0.5 month 3. Development of error parameter estimation program by non-linear least square method. 2.5 months 4. Analysis and evaluation 1 month
Period		5 months, but can be extended as a 10 month project, by including revised version of new apparatus development.
Necessary Background, Knowledge, Skills		Computer programming skills and fundamental knowledge of NC machine tools.
Further Information
Contact Person		Prof. Kimiyuki Mitsui (mitsui@mech.keio.ac.jp) Mr. Kenichiro Fujino (kenichiro.fujino@mmm-keio.net)

Offer from	University	Keio University
	Faculty / Department	Faculty of Science and Technology, Mechanical Engineering Department
	Group Name	Mitsui Laboratory
Research Theme		Experiment and computer simulation on a high speed micro-spindle
Brief Explanation		When measuring spindle rotation accuracy of a high-speed micro-spindle, very low frequency radial motion component is observed. Though the reason has not been made clear, out of roundness of inner and outer ring and rolling elements seem to be a reason for this. In this study, the mechanism of the low frequency radial error will be analyzed through numerical simulation.
Research Steps		1. Experiment and data acquisition 0.5 month 2. Numerical simulation 3 month 3. Compare with the simulation results and experimental results 1 month 4. Evaluation 0.5 month
Period		5 months, but can be extended as a 10 month project, by including measurement of spindle run-out and the data analysis.
Necessary Background, Knowledge, Skills		Computer programming skills
Further Information
Contact Person		Prof. Kimiyuki Mitsui (mitsui@mech.keio.ac.jp) Mr. Kengo Fujimaki (lowspeed64@yahoo.co.jp)

Offer from	University	Keio University
	Faculty / Department	Faculty of Science and Technology, Mechanical Engineering Department
	Group Name	Mitsui Laboratory
Research Theme		Proposal of the Optimum Clearance in Shearing Work for Thin Sheet Metals
Brief Explanation		In general, the clearance between the die and punch is the most important factor in the shearing work of metal plates. For general shearing work of various metal plates, the optimum clearance have been already proposed. But the optimum clearance for various metal plates cannot be applied for thin sheet metals because of size effect due to micro-machining. From these points of view, a small sized stamp out machine has been developed. In order to keep uniform clearances between the die and punch, which is extremely important to discuss about machining accuracy in shearing work, a system to measure the center positions of the die and punch using image processing techniques, and adjust the die and punch positions by PZTs driven X-Y precision micro-mechanical stages. Current hole diameter is 1mm, but in this study we will try diameter range of 100 to 500 mm including not only circular holes, but also rectangular shape holes.
Research Steps		1. Understand the subject and discussion 0.5 month 2. Designing of the optical alignment system and its construction 3 month 3. Experiments on stamp out machining and data analysis 1 month 4. Evaluation 0.5 month
Period		5 months
Necessary Background, Knowledge, Skills		Fundamental geometrical optics Fundamental image processing system Computer programming skills
Further Information
Contact Person		Prof. Kimiyuki Mitsui (mitsui@mech.keio.ac.jp) Mr. Yoshiyuki Kibe (fr010713@hotmail.com)