Coffee Delivery Robot

[Yuveer]

Hey guys

I want to make a coffee delivery robot which will fetch me coffee from the staff room and bring it to my office. The staff room and office are on the same floor. The staff room is just down the corridor.

The robot must leave my office, go through the corridor, turn left and then right, then enter the staff room. Caroline will then place a cup of coffee on it and it should bring it back to me.

I need to develop an algorithm which will ensure that the robot travels straight down the corridor (which is about 13m) without hitting the walls.

I have all types of sensors, such as ultrasonic and infrared.

Any idea's on how i could implement my algorithm?

Regards!

[v01d]

Can you put down tape on the floor? if so you can just make it a line following robot.

[BigKLaxer]

If that's all you need it to do, you could hard code the directions it needs to travel and make it a wall following robot using either a distance sensor to remain close to the wall, or a flex sensor as a sort of whisker.

[newInRobotics]

Line follower would probably be easiest to build, easiest to program and it also would be fairly precise and fast.

[georgeecollins]

Line following is the easiest and the most certain way to do this.  However I am sure it would work fine with a combination of ping / ultrasound sensors and encoders on the wheels.  Encoders are little sensors on the wheels that keep track of how many times they have turned.  Since you are going to follow a consistent path you can probably mostly get there by remembering how many wheel turns it takes to geth through the door, to make a right hand turn and to go down the hall etc.  Ultrasound sensors are great for making sure you don't bump into walls and detecting doorways. 

I would look at the robots that do the Trinity Fire Fighting challenge as inspiration.  There code is often available online.  I have done maze solving robots and would be glad to help if you have more specific software questions. 

Is Caroline your coffee making robot? 

[newInRobotics]

However I am sure it would work fine with a combination of ping / ultrasound sensors and encoders on the wheels.

I don't think You need any of these as if You want robot to follow white line on black carpet, all You need is 2 IR emitter/detector pairs, no shaft encoders, no ultrasonic sensors.

As I'd imagine, in this case robot with 4 IR emitter/detector pairs would do (two at the front and at the back). When robot goes to one side, sensors at the front make sure that robot does not loose its path,  where sensors at the back makes sure to detect when path finishes at on given side. Someone/something puts coffee on the robot and pushes the button, then sensors switch places in their functionality, now the back ones become front ones and and front ones become back ones. Robot goes to the other end of the line and stops. Someone drinks coffee. If more coffee is needed, person pushes the button and robot goes back to ask for some more.

P.S. You could have something like this to make You coffee

[v01d]

you could put the push button in the tray the holds the coffee, so whenever coffee is present the robot comes to you.

bonus points if you use a scissor jack to lift it to your desk (a motor with a screw attached and 2 limit switches for when it is fully extended/retracted.)  or if you are relay fancy you can get some HAYDON linear actuators which you can sometimes pick up on the cheep on ebay.

now if you are truly devious have the tray also read the temperature of the coffee. (thermocouples are cheap)  if the coffee temp drops becomes to cold, have it go get more coffee.  (this will be the most hated feature by your brewer)

I kind of want one of these now... need to finish current robot first.. sigh.