i would like to build an earthbag house, but use large earthbags, about 250 pounds. I have found several mini cranes that will do the lifting. I want the crane to be remote controlled from the point of lifting the bag off the ground until the bag is positioned 8-10 inches from where it should be placed. At that point, I would like the computer to place it automatically.To use an analogy, when parallel parking, once you get the car close to the empty spot, some cars can park themselves. Would a raspberry pi be a good "brain" to control such a machine? What kind of sensors or methods would allow me to place the bags precisely? Obviously I am a newbie at this. I am hoping to get advice and direction here to help me shorten the learning cost and expense.
Building an earthbag home.
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bigbad -
June 16, 2021 at 2:27 PM -
Thread is Unresolved
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RaspberryPi could a good match. to get precision with positioning you will need some sort of feedback. Conventional feedback looks at travel of each joint. feedback resolution, length of each joint and some other factors have a main influence on how precise positioning can be.
in case of robotic arm that feedback is normally built right into the motors that power each axis. Figuring how to add feedback to existing manipulator arm or crane can be a challenge, specially if this is supposed to working outdoors because of other influences such as weather.
There are different types of feedback possible (encoder, resolver, potentiometer etc.) and some of them are absolute, some are not. Absolute means that unit is able to give correct position, without need to search for reference (origin) - even after powering down.
Most common are quadrature encoders and resolvers. In some (cheap) cases, using stepper motors is intentional so that no separate feedback is required, one simply counts steps of the motor (and assumes that it did not skip...)