Keigo Watanabe

Fuzzy feed rate controller for a machining robot

A cast metal is generally produced by using a sand mold. A foamed polystyrene mold is used as the master mold for making the corresponding sand mold. Recently, the development of a flexible machining robot for foamed polystyrene materials is expected in the cast metal industries because of the high cost and inefficiency of conventional large-sized CNC machine tools. In this paper, a flexible machining system integrated with an industrial robot is proposed for foamed polystyrene materials. A compact and light weight tool is developed and attached to the arm tip. The tools feed rate is skillfully regulated by a fuzzy reasoning method. The design of the flexible machining robot controlled using the developed fuzzy feed rate controller is presented for foamed polystyrene materials.

Machining robot for foamed polystyrene materials using fuzzy feed rate controller

Generally, cast metal is produced by using a sand mould. A foamed polystyrene mould is used as not only the master mould for making the corresponding sand mould but also the lost–foam pattern for full mould casting, i.e., lost–foam casting. Recently, the development of a flexible machining robot for foamed polystyrene materials is expected in the cast metal industries because of the high cost and inefficiency of conventional large sized CNC machine tools. In this paper, a machining robot based on an industrial robot is developed for foamed polystyrene materials by applying the already developed robotic CAM system. A compact and lightweight high performance tool is also considered and attached to the arm tip. The feed rate of an end mill is skilfully regulated by a fuzzy reasoning method. The design of the machining robot using the robotic CAM system and fuzzy feed rate controller is presented to efficiently produce foamed polystyrene moulds.

Robotic trajectory following controller with a capability for generating micro vibrational motion along curved surface

A cast metal is generally produced by using a sand mold. A foamed polystyrene mold is used as the master mold for making the corresponding sand mold. Recently, the development of a flexible machining robot for foamed polystyrene materials is expected to be used in the cast metal industries because of the high cost and inefficiency of conventional large-sized CNC machine tools. To cope with the need, we already presented a machining system based on an industrial robot. Industrial robots have been recognized as a typical biomimetic machine pursuing the capability of human arm. The developed robotic CAM system provides a simple interface without using any robot languages between any CAD/CAM system and the machining robot. In this paper, a trajectory following controller with a capability of generating micro vibrational motion is completed for a ball endmill of the machining robot in order to enhance the machining performance of foamed polystyrene materials with curved surface. The micro vibrational motion is online generated along curved surface by post-processing original CL data. The implementation of the proposed controller and removal machining results along curved surface are illustrated.

Viewer, converter and preprocessor for smart machining process using an industrial robot

In this paper, viewer and converter softwares are presented for smart machining process using an industrial robot. The viewers for NC, CLS, DXF and STL files illustrate their surface representation with normal direction vectors. For example, the DXF is a data format developed by Autodesk to realize data interoperability among different makers’ CAD systems. The STL means Stereolithography which is a file format proposed by 3D Systems and recently is supported by many design tools and CAD/CAM softwares. In addition, the converters for DXF and STL files generate the corresponding CLS files with normal direction vectors for machining. Further, the proposed preprocessor allows the developed machining robot to work based on information included in STL files. The convenience and user-friendliness of the proposed integrated system are confirmed through experiments of viewing, converting and machining.

Vibrational motion control for foamed polystyrene machining robot and extraction of radius of curvature for fuzzy feed rate control

There are two serious requirements to machining systems used in manufacturing industries. They are machining quality and efficiency. In this paper, a vibrational motion control is proposed for an endmill attached to the tip of a machining robot to suppress the occurrence of undesirable cusp marks. In addition, the calculation of radius of curvature along discrete CL data is introduced for a fuzzy feed rate controller which can regulate the tangent velocity. The radius of curvature is effective information as a fuzzy input. The effectiveness of the proposed methods is validated through experiments.