A robotic laser cutter trims along a straight line from approach point C(20,10,45) to destination point D(80,−20,15) (dimensions in millimeters).
Step-by-Step Mathematical Solution
1. Direction Vector and Parametric Equations
Compute direction vector v=CD:
v=⟨80−20,−20−10,15−45⟩=⟨60,−30,−30⟩ mm
Using point C(20,10,45) as initial position r0:
x(t)=20+60t
y(t)=10−30t
z(t)=45−30t
2. Symmetric Form
Solve each parametric equation for t:
t=60x−20=−30y−10=−30z−45
Equating the terms yields the symmetric equation:
60x−20=−30y−10=−30z−45
3. Coordinates at x=50 mm Plane Crossing
Substitute x=50 into the symmetric relation:
t=6050−20=6030=0.5
Now solve for the corresponding y and z values:
−30y−10=0.5⟹y−10=−15⟹y=−5 mm
−30z−45=0.5⟹z−45=−15⟹z=30 mm
The laser beam crosses the x=50 plane at the coordinate (50,−5,30) mm.
Real-Life Engineering Meaning & Application
Physical Interpretation: The symmetric equations represent the spatial geometry of the laser line independent of the feed rate. The coordinate (50,−5,30) is the exact spatial point where the beam pierces the critical clamping plane.
Engineering Application: In Computer-Aided Manufacturing (CAM) and automated fabrication cells, collision-detection routines perform plane-intersection checks before running G-code scripts. By verifying the beam coordinate (50,−5,30) against the safety envelope of the physical clamp, engineers avoid catastrophic tool collisions and costly equipment damage.