Undergraduate Student

Alexandre Magno Gonçalves Amorim

Undergraduate Student

Ana Julia de Lima Martins

Undergraduate Student

Isabela Fonseca Souza

Undergraduate Student

Pedro Henrique Lopes Veríssimo

Undergraduate Student

Samuel Souza da Silva

Little John Hardware Architecture

 Little John is a robot composed of two subsystems: a five-DOF manipulator based on the Dynamixel AX18 servomotors and the differential mobile platform Create.


 The hardware architecture available today for use of this robot consists in two Kinects located in the ceiling; markers to define the inertial frame, the Little John frame and any other frame that is important for the task the user wants to perform; a computer to manage the robot control and the system as a whole; and the Little John itself. 

The computer has an Intel Xeon 2.4GHz with 12M cache, 12 GB RAM, Nvidia Quadro and runs Ubuntu 14.04 LTS and ROS Indigo. The two Kinects compose the vision system and can detect the markers in its area range. The ROS Indigo is used to send and receive commands to/from the Little John and the Kinects.

For developers who want to know more about the software architecture, refers to the Little John Tutorial in our wiki.



Frequently Asked Questions

Non MACRO members:

Q. I haven't found the information I was looking for in the website. Where can I look for more information?

A. Please contact Prof. Adorno (adorno at or Prof. Raffo (raffo at


MACRO members:

Q. I'm a new member of MACRO. What should I do?

A. First, make sure that you have access to all our communication channels. The most important one is our email group (macroufmg at, where all official messages are sent. Please talk to your advisor and ask him to include you in the list. Also, take a look at our website to know more about our research group, the people involved, etc.

Q. What kind of information should I send to the email group?

A. This list includes current and former members. Any general information related to our research group that is relevant to all members is appropriate. Below there are some examples of what is appropriate and what is not:

You did a cool video related to your research project and want to share with the group: appropriate. Yes, this is the right place!

You want to be included in the website (or any other MACRO resource) but don't know how and sends an email to the email group: inappropriate. You should talk to your advisor or a senior colleague instead of sending an email to the whole group.

You want to ask the opinion of MACRO members about something (for example, the color of MACRO's new t-shirt), so you start a discussion in the group about it: inappropriate. Although this subject is potentially of everyone's interest, it is a better idea to use of one of those online polls/doodle and send only the link to the group. This avoids endless discussions.

Q. What communication channels, other than email, does MACRO have?

A. Besides email we communicate using a Trello dashboard, whose link you can find at this wiki entry. To request access to this channel, ask for your advisor's authorization and send an email to Brenner Santana (This email address is being protected from spambots. You need JavaScript enabled to view it.).

Another sort of communication channel is our wiki. If you would like to contribute with contents to the wiki, request an account here.

Q. How can I request a place in the laboratory?

A. The organization of the laboratory and all the vacant places follow a hierarchical organization that might depend on the students' date of entrance and on the capacity for their advisors to ask for a place, as well as the date of request. You can check the corresponding list here. Places are allocated exclusively to graduate students.

Q. Can I use the available robots?

A. Yes, as a MACRO member you are able to use any of the robots and devices available. However, you should check the schedule for availability and then create an event specifying your name, the time, and the robots or devices you are going to use. Before using the robots you must be registered as editor of the robots' usage calendar. Ask for your advisor's authorization and send an email to Brenner Santana (This email address is being protected from spambots. You need JavaScript enabled to view it.).







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