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7Resolver--to--DigitalConverter(RDC)

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Hardware R2.2.8 1 1.98.02 en

7Resolver--to--DigitalConverter(RDC)

7.1 Description of the RDC

The RDC card with built--in DSP (Digital Signal Processor) is located in a housing at the base

of the robot and performs the following functions:

-- Generation of all necessary operating voltages from the 27V supply;

-- Res o lve r pow e r s upply f o r 8 a x es ;

-- Isolated power supply of 8 temperature sensors (KT Y 84) in the motor windings;

-- R/D conversion for up to 8 axes (approx. 3 x 4096 increments/motor revolution)

-- A/D conversion for 8 temperature sensors (12--bit resolution);

-- Evaluation of 2 EMT channels (1 EMT);

-- Res o lve r ope n --c irc uit m o nit or i ng;

-- Mot or t e mp e rat ur e m o nit or i ng;

-- Communication with the DSEAT via an RS422 serial interface.

The RDC also has an EEPROM that stores the following data even after the controller is swit-

ched off:

-- Operating hour counter (counts in minutes when the brakes are opened; can be

displayed with $ROBRUNTIME);

-- Absolute position (important for maintaining the mastering), in increments;

-- Res o lve r pos it ion ( t h i s v a lue is c om par e d t o t he a c t ual r e sol v er posi t i o n on power --

up -- tolerance 6 increments), in increments;

-- Calibration data (offset, symmetry).

Moreover, this EEPROM also contains a write--protected area with the boot program for the

processor.

The cable cores of the 6 robot axes are routed into the housing via a special molding and

are plugged directly to the circuit board.

The cables of the 2 external axes are passed through a screwed gland and connected to the

RDC.

Advantages of this independent module:

-- The DSEAT can be smaller and can therefore be designed as a PC module;

-- No functions requiring a +/--12V supply voltage are located on the DSEAT: this

configuration would cause problems, because the PC power supply unit cannot

supply the necessary voltage, especially in the case of --12V;

-- The cables for the resolvers and motor temperature do not have to be routed to

the DSEAT:

 shorter shielded cables (only in the robot),

 no problems of space requirement, stability and cable routing on the DSEAT;

-- The encoder cable contains 6 conductor pairs instead of 20 in the old system:

 thinner, m ore f lexible and cheaper cable,

 instead of a Harting connector, another (smaller, cheaper) connector can be used.

Kuka KR C1 User Manual

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