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How many waypoints would it take? 
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/ Most recent by ebarnett
in Applications

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Olivier_Grenier
Posts: 42
Hello everyone,
We wanted to get your input on how you would apply a sealing material to the part below with a Universal Robots (following the red line). How many waypoints do you think it would take?
Looking forward to your answers.
We wanted to get your input on how you would apply a sealing material to the part below with a Universal Robots (following the red line). How many waypoints do you think it would take?
Looking forward to your answers.
Olivier GrenierLafond
Sales & Marketing Coordinator @ Robotiq
[email protected]
linkedin.com/in/oliviergl
Sales & Marketing Coordinator @ Robotiq
[email protected]
linkedin.com/in/oliviergl
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Since there are around 30 arcs and each arc requires 3 waypoints, I would say around 90.
You're going to need moveP's (will move the tool linearly with constant speed with circular blends, and is intended for some process operations, like gluing or dispensing), some Circle Moves nested in those moveP's, and a couple moveL's for those straight lines.
Almost as simple as it sounds!
What do you think?
Application Engineer
Robotiq
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Ryan Weaver  Automation Engineer  Axis New England
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Sales & Marketing Coordinator @ Robotiq
[email protected]
linkedin.com/in/oliviergl
Application Engineer
Robotiq
[email protected]
Hi,
I am working on a process application – painting, while my trajectory is spline.
Because of the application I need my TCP speed to be constant at every point of trajectory. I made a program using servoj command which moves TCP on projected trajectory. But problem is speed, which is not constant…
Do you have any idea how to make my TCP speed constant?
Thanks
We do this with a project we are developing and we get extremely accurate tcp speeds across the entire move including large rotations of the end of arm as we transition in and out of paths.
@matthewd92 thanks you for fast respond.
My desired trajectory is polynomic function f(x) seen in the picture posted before. TCP speed is created using trapezoid profile, while 10% is acceleration, 80% constant speed (will be used for process application) and 10% deceleration.
Points are created in MATLAB and send to robot Script code.
Time for calculating points: TIME = 0.008s or 125Hz (because servoJ is used as thread in Script code)
Change in xmovement: Δx = Δx + TIME*vi; vispeed calculated trapezoid profile
X Pose: X_x = X_start + Δx
Y Pose: X_y = 173.24*X_x.^5  52.341*X_x.^4  43.105*X_x.^3  1.6338*X_x.^2 + 0.8584*X_x + 0.3668;
Problem is movement in yplane because I can calculated trapezoid profile only in one plane (speed in xplane is constant with trapezoid profile)… How was your method to make constant TCP speed on desired trajectory?
You can download MATLAB code here: https://www.dropbox.com/s/8g2plpepv0av9as/Crating_path.m?dl=0
If you need to use the polynomial function to describe your curve, I suggest the following procedure:
First generate a list of xyz coordinates at a relatively good spatial resolution such as 1 mm. Next compute the arc length at each point in your list:
ds = sqrt(diff(x).^2+diff(y).^2+diff(z).^2);
s = [0; cumsum(ds)];
Then you can generate a trapezoid velocity profile for s that goes from 0 to s(end). If the associated position profile is called s2, you can get the desired position coordinates via interpolation:
x2 = interp1(s,x,s2,'spline');
y2 = interp1(s,y,s2,'spline');
z2 = interp1(s,z,s2,'spline');
@ebarnett, thank you for your answer.
By Multipoint Path node in Copilot you mean Force Copilot?? But how I understand, speed is here constant only between two pair of waypoints and not for all trajectory (from first to last waypoint), am I correct?
And your idea for trapezoid velocity profile works great! Huge thanks!
I also found that servoC (2nd picture) actually do the same without any calculations of trapezoid profile.