原帖中几段翻译内容所对应原文如下：
【Fidia C10-C20】
RTCP
Applied to bi-rotary heads and roto-tilting tables, the RTCP function manages tool length compensation in space, directly from the machine tool.
A 5-axis tool path can therefore be programmed without having to consider the pivot that will be inserted in the NC tool table before the program is executed.
RTCP characteristics:
■ controlled feed at the tool tip
■ look ahead on 5 axes
■ management of orthogonal, angular and eccentric heads
■ “virtual quill”: manages an axis oriented in the tool direction for executing drilling and release movements
■ rotation and/or translation on 5 axes
■ rotation of the reference system (G194): applied to programmed movements and to those executed by jog or by means of the handwheel
The RTCP function can also be used for 3-axis programs: by orientating the head or table manually, the tool tip is maintained in contact with the part.
RTCP and HMS
Combining the RTCP function with the HMS head calibration system is a winning and unique formula in 5-axis milling technology, with clear benefits for accuracy of movement at the tool tip.
HMS
The HMS system is a device designed for measuring and checking continuous and indexed bi-rotary heads and roto-tilting tables. Equipped with 3 sensors connected to the CNC, the HMS system is managed by a specific measurement software. By processing incoming data in real time, the software is able to check and correct geometric error, positioning accuracy and the RTCP parameters for the heads and tables.
HMS is a high-precision instrument and provides an alternative to the traditional checking method using dial gauges. It has many advantages:
■ a drastic reduction in checking time (half an hour rather than an entire day)
■ measurement of all head and/or table positions (not just orthogonal positions)
■ measurement of RTCP parameters
■ automatic insertion of correction values in the CNC.
【1】
http://www./articles/010704.html Most CNC controls have a utility function called tool center point management. Depending on the control manufacturer, this function may be named RTCP, TCPC or TCPM. The utility performs many functions with similar behavior no matter the controller. The key function performed by tool center point management systems is to allow the CNC control to accept fixture offsets and adjust NC data—on the fly—while working in five-axis mode; thereby, allowing one set of post-processed data to work for an entire batch of parts.
The benefit is that an operator need not align a workpiece precisely to the rotary table centerline. A part can be mounted and probed, and the offsets from center can be loaded into the control registers and processed with the NC data during operation. This function can reduce idle time on a milling machine while mounting a part and have the machine tool focus on chip removal. This is a more economical approach than purchasing a secondary pallet and table to allow part mounting while the part on the first pallet is being machined.
Taken one step further, the tool center point management allows a series of parts to be mounted without being precisely located on the machine or without being precisely mounted relative to the remainder of the production lot. So not only can we reduce the labor for mounting parts and the machine idle time, this control function can reduce the cost and preparation time for mounting fixtures and otherwise non-critical mounting surfaces on the workpiece.
【2】
http://www./forums/showthread.php?t=82998 Generically speaking they are the same. But the actual performance of these functions is not in a manual, but inside the software/firmware of the control manufacturers. And they don‘t seem to tell you exactly how they accomplish the mathematics for tool center point control.
There are a few different functions that may be included in the "tool center point" technology concepts.
1. Kinematic transformations (multi-axis) are performed inside the CNC control. A benefit of this is that the CAM software postprocessor need not perform this math. The second benefit is that pivot offsets are held within the machine control register tables. The big benefit of this function is that one NC program can be applied to different machines in your shop that may have different pivot offsets. In the old days (not so long ago), you would have to include the pivot offsets in the CAM postprocessor, and then need different NC code to run the same part on machineA and machineB (same maker and kinematics).
Together with this, feedrate is controlled at the tool tip using math inside the control. This latter point is in contrast to historical "inverse time" modes where the CAM software had to calculate a time (feedrate) for each block.
2. Tool center point management often includes fixture offsets. A part is placed on the machine tool. The local is determined by on-board probes. The position offsets are added to the above-mentioned pivot offsets.
The benefit again is that serial parts can be put on the same machine, located by probe, and one set of NC instructions can cut all parts. The end-user need not spend extra hours "tapping" in a part so that it is located on center within an acceptably small tolerance.
