# ROS Perception in 5 Days **URL:** https://get-help.theconstruct.ai/c/course-support/rosperceptionin5days/13.md?page=1 [Latest](https://get-help.theconstruct.ai/latest.md) · [Categories](https://get-help.theconstruct.ai/categories.md) · [Tags](https://get-help.theconstruct.ai/tags.md) **Page:** 2 --- ## [Using Upper body in my own linux system](https://get-help.theconstruct.ai/t/using-upper-body-in-my-own-linux-system/3852)
**Author:** [@david.gutierrez.11.s](https://get-help.theconstruct.ai/u/david.gutierrez.11.s)\ **Replies:** 4\ **Last updated:** [June 10, 2020, 10:26am UTC](https://get-help.theconstruct.ai/t/using-upper-body-in-my-own-linux-system/3852 "2020-06-10T10:26:20Z")
Hello, im having a lot of troubles to implement the upper body detector and some others detectors in my own linux system. And i dont know how to solve this. The main problem is that it does not detect anything. --- ## [Node error in my code](https://get-help.theconstruct.ai/t/node-error-in-my-code/3043)
**Author:** [@BrayanAndruMontenegro](https://get-help.theconstruct.ai/u/BrayanAndruMontenegro)\ **Replies:** 2\ **Last updated:** [April 14, 2020, 2:16am UTC](https://get-help.theconstruct.ai/t/node-error-in-my-code/3043 "2020-04-14T02:16:52Z")
I am applying exercise one of the unit 1Get Images from a ROS topic and show them with OpenCV on my computer but I get the following error: roslaunch my\_following\_line\_package line\_following\_b.launch … logging to /ho… --- ## [Problem executing roslaunch](https://get-help.theconstruct.ai/t/problem-executing-roslaunch/2997)
**Author:** [@BrayanAndruMontenegro](https://get-help.theconstruct.ai/u/BrayanAndruMontenegro)\ **Replies:** 1\ **Last updated:** [April 9, 2020, 5:23pm UTC](https://get-help.theconstruct.ai/t/problem-executing-roslaunch/2997 "2020-04-09T17:23:34Z")
I am applying the example of basic ros in 5 days on my pc and the following error occurs to me, could you please help me on how I can solve it, thanks ERROR: cannot launch node of type \[simple\_pkg/simple.py\]: can’t loca… --- ## [Blob detection after exercise U1-1 does not work correctly in unit 2](https://get-help.theconstruct.ai/t/blob-detection-after-exercise-u1-1-does-not-work-correctly-in-unit-2/2936)
**Author:** [@dave.vandermeer](https://get-help.theconstruct.ai/u/dave.vandermeer)\ **Replies:** 2\ **Last updated:** [April 6, 2020, 2:11pm UTC](https://get-help.theconstruct.ai/t/blob-detection-after-exercise-u1-1-does-not-work-correctly-in-unit-2/2936 "2020-04-06T14:11:06Z")
I am working on the perception module in unit 2 in preparation of exercise U1-2. I manage to get the red ball in the field of view of the robot, I can use the GUI to get the RBG and the YUV values. When I fill them into … --- ## [Exercise U3-1 too many tables detected](https://get-help.theconstruct.ai/t/exercise-u3-1-too-many-tables-detected/2210)
**Author:** [@fgenestcvdl](https://get-help.theconstruct.ai/u/fgenestcvdl)\ **Replies:** 2\ **Last updated:** [March 5, 2020, 10:47pm UTC](https://get-help.theconstruct.ai/t/exercise-u3-1-too-many-tables-detected/2210 "2020-03-05T22:47:27Z")
In the exercise 3.1 the number of table detected is changing randomly before a start moving i have table\[0\] and table\[1\] and as i move forward once in a while it goes up to 4 tables detected simultaneously. How do i cho… --- ## [3d ans 3d object detection questions](https://get-help.theconstruct.ai/t/3d-ans-3d-object-detection-questions/2211)
**Author:** [@fgenestcvdl](https://get-help.theconstruct.ai/u/fgenestcvdl)\ **Replies:** 2\ **Last updated:** [February 12, 2020, 3:07pm UTC](https://get-help.theconstruct.ai/t/3d-ans-3d-object-detection-questions/2211 "2020-02-12T15:07:44Z")
In order to have to have 3D detection do we need to do both 2D and 3D image training ? When we have many object and many images of all of them let say 10 coke can images 20 beer can images Is there a way to tell the … --- ## [Questions for Exercise U1-3](https://get-help.theconstruct.ai/t/questions-for-exercise-u1-3/1672)
**Author:** [@youngyangcs](https://get-help.theconstruct.ai/u/youngyangcs)\ **Replies:** 1\ **Last updated:** [December 12, 2019, 2:14pm UTC](https://get-help.theconstruct.ai/t/questions-for-exercise-u1-3/1672 "2019-12-12T14:14:40Z")
Hi, Thanks for providing this amazing course, but I have a few questions that couldn’t understand When the Mira robot is static, why I can still read the velocity from JointState? I don’t understand the codes from… --- ## [The counter doesn't show in MASK](https://get-help.theconstruct.ai/t/the-counter-doesnt-show-in-mask/1679)
**Author:** [@youngyangcs](https://get-help.theconstruct.ai/u/youngyangcs)\ **Replies:** 1\ **Last updated:** [December 12, 2019, 1:51pm UTC](https://get-help.theconstruct.ai/t/the-counter-doesnt-show-in-mask/1679 "2019-12-12T13:51:46Z")
I’m doing the exercise U2-5, When I add the function cv2.findContours, the mask doesn’t show the path but the res can still draw the red dot on the yellow counter, can anyone help me with it? --- ## [I can't run 'gedit' and the packages are too slow](https://get-help.theconstruct.ai/t/i-cant-run-gedit-and-the-packages-are-too-slow/1616)
**Author:** [@dkfkgks1218cf7a77dc90654b63](https://get-help.theconstruct.ai/u/dkfkgks1218cf7a77dc90654b63)\ **Replies:** 1\ **Last updated:** [December 2, 2019, 2:06pm UTC](https://get-help.theconstruct.ai/t/i-cant-run-gedit-and-the-packages-are-too-slow/1616 "2019-12-02T14:06:12Z")
I’ve typed ‘gedit’ in your simulation terminal so far, but it has NEVER gone well at all. ALL I can get is just: 'cannot found command ‘gedit’ ’ What should I do??? It seems if I can’t access to gedit, I would never … --- ## [Follow Along on My Own Linux System](https://get-help.theconstruct.ai/t/follow-along-on-my-own-linux-system/1256)
**Author:** [@rich](https://get-help.theconstruct.ai/u/rich)\ **Replies:** 11\ **Last updated:** [October 31, 2019, 3:28pm UTC](https://get-help.theconstruct.ai/t/follow-along-on-my-own-linux-system/1256 "2019-10-31T15:28:27Z")
While there is some value in doing these courses in the Ignite system, I find I’m missing a TON of how I could actually do this on a production system, which is why I’m taking the Perception course. So, I don’t have the… --- ## [ROS Perception in 5 days: 4Surface and object recognition extra exercise answer needed](https://get-help.theconstruct.ai/t/ros-perception-in-5-days-4surface-and-object-recognition-extra-exercise-answer-needed/986)
**Author:** [@stevensu1838](https://get-help.theconstruct.ai/u/stevensu1838)\ **Replies:** 1\ **Last updated:** [October 10, 2019, 6:16pm UTC](https://get-help.theconstruct.ai/t/ros-perception-in-5-days-4surface-and-object-recognition-extra-exercise-answer-needed/986 "2019-10-10T18:16:05Z")
Can you please provide reference answer??? EXTRA Exercise U3-5 Do the following: Spawn two objects on the table and make them move on the table. Detect one of the objects. Track that object and make the Fetch robot t… --- ## [Couldn't understand the following portion in exercise U1-3](https://get-help.theconstruct.ai/t/couldnt-understand-the-following-portion-in-exercise-u1-3/509)
**Author:** [@shiruraditya](https://get-help.theconstruct.ai/u/shiruraditya)\ **Replies:** 2\ **Last updated:** [August 26, 2019, 8:12pm UTC](https://get-help.theconstruct.ai/t/couldnt-understand-the-following-portion-in-exercise-u1-3/509 "2019-08-26T20:12:07Z")
Hi, I couldn’t understand the following portion of solution code for exercise U1-3. Could somebody please explain the logic in trigonometric calculations? Any url for understanding the theory would also be a great help! … [Previous page](https://get-help.theconstruct.ai/c/course-support/rosperceptionin5days/13.md)