Willem Weertman

Willem Weertman

Anchorage, AK

More

Haven't backed any projects yet! 

Thank you David, I will try to keep the posts going
Dec 31, 2020
Understanding how octopuses use scent to find food
View comment
Thanks Anna!
Dec 30, 2020
Understanding how octopuses use scent to find food
View comment
If I am understanding this correctly. Something of known size so we can translate pixels into measurements of known length. As well as a way to count time. Time first. The camera counts time with an error of a few nano seconds, the video recordings are captured at 10 frames per second to save storage space, I have many weeks of footage. The time error is very low. Space is a bit trickier due to the spherical distortion of the lense. The python openCV library has an open source tool for calibrating cameras https://docs.opencv.org/3.4/d4/d94/tutorial_camera_calibration.html. By calibrating the camera we can flatten our coordinates using the calibration matrix. once our coordinates are flattened we can measure an object of known size on the bottom of the tank and then translate pixels to lengths. The camera is about as perpendicular to the bottom of the tank as I could get it. So the object measured at one point on the plane of the tanks bottom should reflect sizes elsewhere on the plain with reasonable accuracy. It is ~20 pixels per inch.
Dec 18, 2020
Understanding how octopuses use scent to find food
View comment
No sliced sushi :)
Dec 18, 2020
Understanding how octopuses use scent to find food
View comment
Yeah, would not want to be eaten by an octopus, would be one of the worse ways to go.
Dec 18, 2020
Understanding how octopuses use scent to find food
View comment
Thank you Peter! so am I! It is a fun project.
Dec 07, 2020
Understanding how octopuses use scent to find food
View comment
I'll post that
Dec 05, 2020
Understanding how octopuses use scent to find food
View comment
thanks Cindy!
Dec 04, 2020
Understanding how octopuses use scent to find food
View comment
Thanks Mehmet, as always, good to hear from you!
Dec 04, 2020
Understanding how octopuses use scent to find food
View comment
This plot is a part of my investigation into comparing the motions of octopuses during odor tracking vs typical locomotion. You can actually see in the data 3 'veins' going left to right. I believe those are largely the food source influenced veins. I have noticed the octopuses doing an interesting 'stepping' patterns with their arms during pauses in locomotion that at least annecdotally seems to correlate with trajectories that end up with them finding food by moving upstream to the food. This stepping as well as some other features might come out as correlates with odor tracking. I would like to see if the stepping is real. with better quantification of the odor plumes by reconstruction of plumes with a good laser sheet we could make accurate guesses on if certain motions they make correlate with edges of the plumes. hmmm. you know, given enough data you might be able to predict the motions of an animals with a markov chain model. https://github.com/YttriLab/B-SOID check this out, really cool software for segmenting behavioral motifes from coordinate matrices.
Dec 03, 2020
Understanding how octopuses use scent to find food
View comment
So am I!
Dec 03, 2020
Understanding how octopuses use scent to find food
View comment
thank you Kimmy!
Dec 01, 2020
Understanding how octopuses use scent to find food
View comment
Show more comments