Mitsubishi Electric CR750-Q Instruction Manual page 538

5Functions set with parameters
Point
If the collision detection function is enabled for the entire program, the probability of erroneous detection
becomes higher accordingly. Hence, the detection level must be lowered in order to eliminate erroneous
detection. As a result, the interference detection sensitivity may be lowered for operations for which colli-
sion detection is required. Thus, it is a good idea to use the collision detection function only for operations
that may cause interference, so that the detection sensitivity may be kept high when in use.
Point
If the collision detection function is enabled, the execution time (tact time) may become longer depending
on the program. In order to reduce influence on the tact time, use the collision detection function only for
operations that may cause interference, rather than enabling the function for the entire program.
*Adjustment of collision detection level
Adjust the detection level (sensitivity) at program operation according to the robot operation. As a reference,
an example of adjustment procedure is shown below. be sure to set the workpiece condition and hand con-
dition properly as well in order to estimate the torque accurately.
Table 5-24:Example of detection level adjustment procedure at program operation
Step
1 Add the ColLvl and ColChk commands before and after operations for which the collision detection function
is used.
2 Set the detection level low (the argument of the ColLvl command is set to a large value such as 300) in
order to prevent erroneous detection of interference.
3 Run the program and monitor the value of J_ColMxl in the target operation. Note that the value may fluctu-
ate; repeat the target operation several times and record the J_ColMxl value each time.
4 Obtain the maximum value for each joint axis from multiple J_ColMxl values and add some margin (e.g.,
20%) to the value. Then set this value as the argument of the ColLvl command.
5 Set the value obtained in step 4 to the ColLvl command and run the program to check that no erroneous
detection occurs at the operation for which the collision detection function is used. If an interference is erro-
neously detected, gradually increase the value of the argument of the ColLvl command to lower the detec-
tion level until no erroneous detection occurs.
Point
When the operation speed is changed, it may become necessary to change the detection level. Operate
the robot at the actual operation speed and then adjust the detection level.
Point
If the collision detection function is used for multiple robots, it may become necessary to adjust the detec-
tion level for each robot even for the same operation, due to individual differences of robots due to differ-
ences in motor characteristics and usage environment. Note also that if there are several robot models,
the detection level must be adjusted for each robot.
When using the controller software version R6b/S6b or later and RT ToolBox2 Ver.3.40S or later, it is possi-
ble to choose "Ref. value of COL level"(reference value of the collision detection level) for the oscillograph
function of RT ToolBox2. This function can be easy to adjust the detection level of ColLvl command. Refer to
Page 519, " 3) Supplement"
*Behavior when interference is detected
If an interference with peripheral devices or similar is detected during program operation, an error numbered
in the 1010's (the least significant digit is the axis number) is generated and the robot is stopped as the
servo is turned off. If the robot is in the NOERR mode, no error is generated, but the robot stops as the
servo is turned off (an error numbered in the 1010's will be recorded in the error history, however).
5-518 About the collision detection function
for details.
Description