2
$\begingroup$

I took a course to have a better understanding of drones and their design. At the end of the course there was a test question that I got wrong and I would like to understand why.

I was supposed to select the choices that best describe SLAM.

and the possible answers were:

  1. Estimates the location of features in the environment?
  2. Controls the robot's flight through the environment?
  3. Causes the robot to avoid obstacles in the environment?
  4. Navigate in a cluttered environment?
  5. Estimates the position and orientation of the robot with respect to the environment?

At first I knew that at least 3 and 4 were right because I watched a drone doing these things. I also thought that the last answer was linked to these two so I said yes to it too. Finally, I thought that the only thing that was still controlled by the user would be the flight...

Yet I failed again... Therefore what does Simultaneous Localization And Mapping (SLAM) software do?

$\endgroup$
  • $\begingroup$ What exactly are you asking? $\endgroup$ – Paul Jun 9 '16 at 16:18
  • $\begingroup$ Simultaneous Localization And Mapping (SLAM) software runs SLAM algorithms. You need to elaborate a bit more. $\endgroup$ – CroCo Jun 9 '16 at 16:50
  • 1
    $\begingroup$ SLAM does, or at least assists, several of the items in the list. Were you supposed to select one answer only (i.e. it's a multiple choice question), or were you supposed to select the choices that best describe SLAM? $\endgroup$ – Andy Jun 9 '16 at 16:59
  • $\begingroup$ @Marine1 I tried to improve the english of your question. Does it look ok to you? Does it ask the question you wanted? $\endgroup$ – hauptmech Jun 10 '16 at 21:30
  • 1
    $\begingroup$ @andy, is the question clear enough that we can unblock and get some better answers? $\endgroup$ – hauptmech Jun 12 '16 at 23:33
6
$\begingroup$

Localization is the process of estimating the pose of the robot the environment. Number 5 in your list. Mapping is estimating the position of features in the environment. Number 1.

2, 3, and 4 are not related to SLAM. They are all part of a complete robot system for which SLAM makes up yet another part. The software for a professional or research drone will have subsections that do flight control, obstacle avoidance, navigation (planning), SLAM, and other functions.

So you are correct in that you saw a drone do all those things, but SLAM is only one part of a robots software.

All this is a very simplistic view. In practice we never truly know the environment. We are estimating pose in the map, hoping it is the same as the environment. We build the map with feature positions but often have false readings of features, or mis-identify the same feature as being two separate ones. Few SLAM approaches consider features that move in the environment.

$\endgroup$
2
$\begingroup$

Which software?

  1. Yes, It creates map from its starting point. And robot locates itself in its generated map when generating map.
  2. It is using laser data to locate robot in map, when process starts, map's first part is the first laser scan data. When the robot moves, slam reads odometry data, and locates robot via odometry and laser. Even if odometry is poor, it corrects location via laser scan match.
  3. No, its not a job of slam. Avoiding obstacles is a job of navigation, The navigation must calculate best path with avoiding obstacles. Slam is Simultaneous Localisation and Mapping, it generates map and locates robot on it.
  4. I didn't understand what you meant, yes it can explore cluttered places but navigation isn't its job.
  5. Referring to answer 3, Thinking about environment isn't job of slam too :) It's navigation's or driving people's job.

Also if you didn't please take a look at this SLAM video.

$\endgroup$
  • $\begingroup$ Thank you for your answer, I made a mistake in question 2: it was Controls the robot's flight through the environment?. And refering to your first phrase, I'm talking about SLAM: en.wikipedia.org/wiki/Simultaneous_localization_and_mapping $\endgroup$ – IggyPass Jun 12 '16 at 19:32
  • 1
    $\begingroup$ @orhan-gazi-hafif 'with respect to' is an idiom that means 'relative to'. In other words, 5 is localization. $\endgroup$ – hauptmech Jun 12 '16 at 23:48
  • $\begingroup$ Hi @hauptmech, thank you for corrections. Please feel free to edit my answer, I learned English myself, from internet. I'm using Tanzanian English :P $\endgroup$ – Orhan G. Hafif Jun 13 '16 at 20:08
  • 1
    $\begingroup$ Hi @Marine1, I think Section 3 and 5 are answering the section 2. $\endgroup$ – Orhan G. Hafif Jun 13 '16 at 20:16
  • $\begingroup$ @orhan-gazi-hafif Your english is good. You should edit your answer if you want. $\endgroup$ – hauptmech Jun 15 '16 at 9:41
0
$\begingroup$

Sir The answer to this question is 1&5,as SLAM is used to map the location based on the landmarks.So to do this it has to estimate the location of the features and also every robot must estimate its own position so the it takes the help of SLAM to estimate its position and orientation.

for more information I'm sharing the site from which I read about slam

https://www.gislounge.com/robotic-mapping-simultaneous-localization-and-mapping-slam/

$\endgroup$
0
$\begingroup$

My bet is 1 & 5. The agent or robot quickly orients itself to its environmental position. 1 satisfies this question. 5 satisfies the agent requirement.

$\endgroup$
-2
$\begingroup$

First and last points are correct

$\endgroup$
  • $\begingroup$ Welcome to Robotics Ankita Gupta. Thanks for your answer but we are looking for comprehensive answers that provide some explanation and context. Very short answers cannot do this, so please edit your answer to explain why it is right, ideally with citations. Answers that don't include explanations may be removed. $\endgroup$ – Mark Booth Jul 5 '18 at 15:32

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.