we are pretty new to robotics and all the knowledge in it is pretty new. Currently we are in the process of making a mobile robotic manipulator for our engineering graduation project.
Though we have completed the mechnial kinematic parts, presently we are in the process of figuring out how to fix various electronic components. From basic calculation we have calculated the necessary torque and force required at various joints. But now that many of the components are here we are pretty confused as to what goes where.
the bot basically have
- 5 Servo motors(high torque, heavy duty),
- 5 Gear Motors
- assortment of sensors
- IR, Ultra Sound
- Laser ranger finder
- force/pressure sensor
- tilt sensor
also we have in possesion an
- Arduino Mega 2560 REV3 Board
- Arduino Uno Rev3.
now the confusion is how to connect these vaious components. Especially the gear motor and stepper motor. Do the gear motor require any special setup? or can it be directly connected to the board? also what is the process in connecting the servo motor to the board and the various sensors?
Some of your questions can be answered, but,
I am sure some of the people here would like to know how you plan on constructing the platform (what is the generic layout that you have in mind for all of your actuators and sensors?).
To start with you will need stepper motor drivers that can handle the current and voltage of your stepper motors. Your gear motors will require a similar circuit, more typically known as motor drivers. Connecting the sensors and the motors will require the microcontroller (Arduino in your case).
If you offer information relating to the layout of your planned robot, you may get more useful information. My current concern is that you are considering trying to mount large heavy motors at the joints, and, not be able to move anything else, because the motor mass is eating up all the torque of the motors closer to the base.
Design Specification & Correction
I’m extremely sorry for the mistake, now corrected, it is “Servo Motors” and not “Stepper Motors”.
The design we have considered while making this mobile manipulator is
It is very similar to the above mentioned bots. the manipulator is an articulated, sprocket and chain driven one with 5 dof and all main servos mounted at the bottom link similar to XR4 (http://www.hitecrcd.com/products/analog/giant-scale/hs-805bb.html). and the mobile base have a the following gear motors and is planned to have skid steer. (http://www.nex-robotics.com/products/motors-and-accessories/60-rpm-side-shaft-super-heavy-duty-dc-gear-motor-2.html)
the sensors used are as following:
To answer your question about servos,
I will say that you can power a few servos from your arduino. Some form of shield might be found useful though, because, servos have a standard 3 pin layout, and, you won’t find that layout on a standard arduino board. Current draw is the issue you need to be concerned with, if you try to drive the servos from the same 5v supply that you feed to the arduino.