can fliper

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bloody-orc

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The task is to build a robot capable of finding objects within the designated competition ground and turning the objects upside down.
The robot has to start from the designated start area and pass through the gate located in the wall between the start position and the objects.
Mechanical connection of the robot with any object outside the competition ground is prohibited. Also, any kind of human intervention via any kind of communication to the control of the robots is forbidden during the competition.
The competition time limit is the maximum period of time for completing the pre-defined task. The time limit is 10 minutes. A team is allowed to withdraw the robot from the competition ground before the termination of competition time limit, if given the permission by the jury.
The winner is the team whose robot has turned the largest number of objects into the right position on the competition ground during the competition time limit (10 minutes).

Competition ground:

The competition ground is a square of 4 x 4 m. At one side of the competition ground, there is a separated area (home) of 100±3 cm. The start area, 50x50 cm, is located in one of the corners of home. The central square of the competition ground including the objects is 4 x 3 m.
The height of boundaries surrounding the competition ground is 10 cm and all walls and boundaries are of white colour.
The gate separating home from the central part of the competition ground is 50±1 cm wide. The gate is edged from the sides and upside with the gate frame (height in the middle 40±1 cm, radius of upper corners 20±1 cm). The material and colour of the gate is undefined.
The location of the gate in the wall separating home from the rest of the competition ground will be selected randomly.
Ten objects will be placed randomly into the central part of the competition ground. The minimum distance of each object from each other, from the boundaries and from the walls is 50 cm. For training purposes, a special training configuration of the competition ground will be used.
The robot should neither move over the boundaries of the competition ground nor over the walls on the competition ground.
The surface of the competition ground is a floor area with a flat surface cover (parquet, tile, etc.).
The objects are cylindrical objects with closed ends, diameter 53±1 mm and height (from one edge to another) 134±1 mm, (e.g. painted Red Bull cans). The mass of each object is 250±10 g. The objects are painted half-black, half-white and placed vertically on one of the ends of the cylinder.
The initial position of the objects is white end down. The robot has to turn the objects upside down. The objects have to stay in the upright position (i.e. black end down) supported only by their own weight.
Every object that is properly turned upside down gives 1 point to contestants.

Additional requirements:

Robot, including its manipulators and other auxiliary parts, has to fit into the start area.
It is forbidden to set any other objects except robots to the competition ground or closer than 1 m from the competition area. During the competition the members of robot teams are allowed to stand behind the boundary near the start area or in the area designated for general audience.


What is the best way to do this task? How to flip the cans?

All help is useful...

-Rain-
 

Divide and conquer... you have several tasks

1.) mobility and navigation
2.) locating objects
3.) grasping / interacting with objects..
4.) flipping objects

Since you need only flip cans... I would imagine a gripper powered by stepper motors would be the best bet.

1) locate object.
2) grip object
3) lift object some amount x
4) verify object is still gripped (opto sensors or the like)
5) if it fell down, its orientation may be unknown, you could try again or move on after 2 repeated failures to grip & lift.
6) if gripped ok, rotate 180 degrees.
7) verify object is still gripped..same as 5
8) move it down by x - small amount to avoid smashing
9) let go and move on...

These are the kinds of things I would be thinking about...
 
well yes i think that this is the theory of it but the mechenic part of it :? :cry: how to rise the can? how to grab it? how to turn it? to many questions :? i have tried to build some ways but i tell you the crabing is the hardes part cause you have to crab it hard and the can is aluminium (non magnetic and slippery material)


and the second hard part is the locating of the cans. How to locate them and to see where to go WITHOUT crashing in others?
 


A common method of navigation sensors uses ultra-sound. From what I understand, alot of people will use old polaroid camera rangefinders.. You can also buy these units seperately. The idea is, it sends out a pulse of ultra-sound frequency (a burst) and a receiver listens to the return. Based on the amount of time from send to receive, it calculates distance to object and you can access the device to get that distance.

As far as the grabbing goes, buy a set of motorized grippers from the surplus market and make sure they are lined with rubber strips.. then it is simply a matter of controlling the stepper motor (you will need a driver circuit)

I am not quite sure what specifically you don't feel confident about.
 
well i'm facing the biggest problem off all: the $$$ :wink: and in Estonia there is not mutch stores to buy stuff and most of the prices are sky high :x so i cant use ultra sound however i can use IR beams as sensors. But as I can understad you have used stepper motors and maybe you can tell me that are the steppers in old printers powerfull enough to lift, tur, and crab the can and how mutch gears do i have to use?
 

What is the weight and dimensions of the object you have to lift?
The steppers in old printers are probably ok to use for this but they might
have other limitations that you won't like for your project.

IR beams have been proven to work as well. My only comment is the range will be much much smaller. You will almost have to be bumping into the object before you can really see it.

Have you searched the web for example IR & gripper designs? You will find alot.
 
Optikon said:
What is the weight and dimensions of the object you have to lift?
the weight is 250gramms and the dimentions are 53 mm diameter and the height is 134 mm.
Optikon said:
Have you searched the web for example IR & gripper designs? You will find alot.´
well I googeled and tried to search the gripper but none of them were the things what i was looking for: all were too massive and mostly grabbing from the top side. Or maybe you have found something else and better? :cry:
 

Ok take a look at this:
https://scientificsonline.com/product.asp?pn=3052290&bhcd2=1093624030

if you cannot find a kit just for a gripper construction, look at how this kit
does it and come up with your own design. It doesnt have to be that expensive if you use common metal brackets and scrapped out stepper motors.
 
btw, does the can HAVE to be lgrabbed turned and dropped, i didnt read all the breif but woulkdnt it be easier, if you alowed, to have some kind of long thin sheet of metal or whateva at an angle to slide under the can, and then have fast motors or hydrolics to flip the metal up throwing the can across the room?
 
well i suggest you to read the breaf. you will only get the point when the can is upside down on tehe ground. :wink:
 
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