I am totally new in robotics. I want to track a person walking in a certain track, please suggest me how can i select the DC motor like gear dc motor or servo dc motor, i also want to use the encoder and also please suggest me how to select approprite voltage and RPM of the motor. in addition the motor control driver best suit for that platform.
thanking you all in advance.
Biswas
Could you clear a few things up please?
Dear: Biswas
Just to let you know the appropriate voltage, wattage, rpm, and torque all depends on what you need for a robot. My robot I am building I need something with 100 rpm and as much torque as I can get. Also I would recomend searching pololu and servo city for motors and motor drivers. I would also recomend looking at robotshop for servos and pololu for servos. Good Luck!!!
From: Noah
**please explain me with an example( i am tracking a person) **
Dear Noah,
Thank you for your comment regarding this post.
i am traking a person with 4W drive robot. i want to use only two wheel motorized and two is in option. it depends.but two is fixed. i am suppose to use either DC gear motor or stepper motor. i recon DC gear motor and doing some work out on its advanges and disadvantages.
If the weight of robot is 1kg altogether and i want to move it 5 foot/sec up to 8m distance.
Now how do i know the approprite RPM and voltage. i did review the robotshop adn pololu as well but just didnt get my answer. please suggest me how can i calculate RPM and motor voltage that i need from 1kg robot weight, 5 foot/sec its movement and total distance travel need to be 8m in a very simple way.
Thanking you in advance.
Regards,
Biswas
Well there is not too much to know about this.
Dear: Biswas
Just to let you know if you know what you want from a robot it shouldn’t be too hard to determin your need for motors. Just to let you know you don’t need to know the exact torque of a motor, know the exact rpm, and you do need to know the voltage and wattage of the motors. The reason you do not need to know the exact rpm and torque is because it is fairly easy to over estimate what you need for a robot motor and I tend to do that quite a lot. The reason the voltage and wattage is so important is because you need to know this to drive the motors.
What I typically do since it is fairly easy to determin what I need from a motor is I go looking at several motors and I test each of them on my robot and whichever I like from my motors is the motor I’ll use.
Just to let you know there is no easy way to determin what you need from a motor. I tend to overestimate what I need and if it works it works. I also over my years of experience can tell what is practical and what is not by just looking at motors and their statistics. Good Luck and please check out those robot companies for motors that I suggested.
From: Noah
An example!!!
Dear: Biswas
Very sorry I forgot to give you an example. Just to let you know I am building a two wheel self ballancing robot. The robot is very small and needs as much torque as I can get. I know something with around a 100 rpm will do me good because I have a wild guess that from my experience with seeing 100rpm motors rotate that should be good enough. Because my robot is so small and because it needs a lot of torque and high voltage I used this motor shield and I also used these motors. So good luck!!!
From: Noah
Dear Noah,i really
Dear Noah,
i really appriciate your suggestion regarding my confusion. Based on your experience, i do accept your suggestion as well. But i think that not the right way to choose the approprite motor RPM and voltage. There might be some formula to estimate this. let suppose we can choose the size of wheel as per of our robot size and that fit in our motor from different source of internet. cuz we think it does’t really matter but it does. So as i know one formula to estimate tte size of the wheel as
velocity= circumference*rpm
velocity = diameter * pi * rpm
from this i will know the approxiate wheel size and it efficiency. likewise if i know any approprite formula to estimate for the RPM and voltage i would be so happy based on weight and distacne travel or any other component.
Thanking you again for your valuable suggestion.
Regards,
Biswas
Robot Dynamics…
Perhaps this link can provide some answers:
http://www.societyofrobots.com/mechanics_dynamics.shtml
** please explain me based on color tracking robot**
Hello Machina,
Thank you very much for the link. Yes this link is very useful. I already reviewed and did practice some formulas from here
and that works practically.
If you dont mind can i ask you one question ?
DC motor--------motor controller------microcontroller--------power supply-----Wi-fi
how do you defined relationship between each component? or how they work with eachother.
sorry this might be very simple questiona and it bothered you but i want to learn from the scractch.
As i know we will send the command to microcontroller and then microcontroller send the command to the motor controller. so we can control the motor as per of our requiremnt. that means the controll of our require Motor RPM is in our hand. if i bought like 300rpm motor then i can make it 50rpm as per of my requiremt with the help of motor controller or as per of our requremet but between its capacity. is it right ? and one more thing if i bought 300 rpm motor and i need to drive it 5 foot per sec up to 8m. how can i set the motor then ?
Thanking you for your best answer in adnvacne.
Regards,
Biswas
Okay I am sorry and cool then.
Dear: Biswas
Very sorry my suggestions weren’t as good as they could have been. I am also am glad you found them at least somewhat helpful. You should know I can kinda guess what makes a good motor a good motor depending on what I am doing but I don’t think that is always the best method. I wish you good luck and I will be following this forum, Thank you,
From: noah
