Galil Motion Control DMC-42 0 Series, Руководство пользователя

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When AV is used as an operand, _AV returns the distance traveled along the sequence.
The operands _VPX and _VPY can be used to return the coordinates of the last point specified along the path.
Example:
Traverse the path shown in Figure 6.7. Feed rate is 20000 counts/sec. Plane of motion is XY
VM XY Specify motion plane
VS 20000
Specify vector speed
VA 1000000 Specify vector acceleration
VD 1000000 Specify vector deceleration
VP -4000,0 Segment AB
CR 1500,270,-180 Segment BC
VP 0,3000 Segment CD
CR 1500,90,-180 Segment DA
VE End of sequence
BGS
Begin Sequence
The resulting motion starts at the point A and moves toward points B, C, D, A. Suppose that we interrogate the
controller when the motion is halfway between the points A and B.
The value of _AV is 2000
The value of _CS is 0
_VPX and _VPY contain the absolute coordinate of the point A
Suppose that the interrogation is repeated at a point, halfway between the points C and D.
The value of _AV is 4000+1500 +2000=10,712

The value of _CS is 2
_VPX,_VPY contain the coordinates of the point C
Figure 6.7: The Required Path
Vector Mode - Mathematical Analysis
The terms of coordinated motion are best explained in terms of the vector motion. The vector velocity, Vs, which is
also known as the feed rate, is the vector sum of the velocities along the X and Y axes, Vx and Vy.
Vs Vx Vy
 
2 2
The vector distance is the integral of Vs, or the total distance traveled along the path. To illustrate this further,
suppose that a string was placed along the path in the X-Y plane. The length of that string represents the distance
traveled by the vector motion.
The vector velocity is specified independently of the path to allow continuous motion. The path is specified as a
collection of segments. For the purpose of specifying the path, define a special X-Y coordinate system whose origin
is the starting point of the sequence. Each linear segment is specified by the X-Y coordinate of the final point
Chapter 6 Programming Motion ▫ 70 DMC-42x0 User Manual
C (-4000,3000)
R = 1500
B (-4000,0)
D (0,3000)
A (0,0)