Let's Make Robots!

Search and Rescue

This challenge is inspired by a local event, where kids are remote controlling robots through a maze like course to find a small Teddy bear, grab it (with velcro) and drag it to the start point. But is this possible to do autonomously? I'm sure it is! 

So here is the challenge: build an autonomous robot that is capable to drive through a maze like environment, find a small Teddy bear, grab it by what ever means and bring it to the starting point. The maze can be made out of card boxes, books, whatever you have handy and it should have at least 4 turns before the position of the bear and the hallways width should be at least 12". The robot shloud be smaller than 12" and can't look over the walls. You can build a 2 wheels, 4 wheels rover, biped, quad, hexapod... anything you like. No remote processing is allowed, that means no link to an external computer is allowed. You can't moddify or add anything to the Teddy bear to make it easier detectable, but you can wrap around it a velcro collar so the robot may grab it easier. Make a video of your robot rescueing the Teddy bear and post a link to it here.

The winner will be decided by a community vote, still need to figure that out how's going to happen, a poll might work, but I don't see a way to add it to the challenge.

There will be prizes available:

- a µBotino V3 kit and a USB-serial cable

- a Robot Builder's Arduino kit and a USB-serial cable

- a Robot Builder's Shield V3 kit and a mini Breadboard


Update, Sept. 26th, 2011:

Since no robot was entered by September 22nd, I have granted an extension of the end date to September 25th. Only one robot was completed by this time, by Sebathorus, so I declare it winner of the First Place. But, since there were others who expressed interest in participating, I am going to make a second extension, until the end of the month. I hope at least 2 more robots to be entered. Come on people! I've got some kits to give!


Update, Oct. 1st, 2011:

The main reason behind this challenge was the old robot builder's dream: robot, fetch me a beer. I thought to bring it to you guys step by step. First, build a robot that is able to find an object and retrieve it. Best built is with a gripper and sensors that scan left-right and look for the object. After you did wall following, try to add encoders and remember your path and after you got the object, get back on the shortest path (maze solving). Build the gripper strong enough so it can pick up a beer can as the retrieved object. Add a voice recognition module and say the magic words: Robot, fetch, a beer! My MiniEric robot can almost do that (can lift only an empty can, not a full one). Can yours?

I removed the end date for this challenge, it will be still ON until the first robot that is able to fetch a (full) beer can left on the floor is demonstrated. No maze required, just house navigating, have the beer on the floor in front of the refrigerator in the kitchen and start the robot in front of the living room couch. The robot must find it's way through house clutter. Post the video and code for the robot in your robot page here on LMR. Prize? I don't know yet, but it's going to be something in the $100 range. Perhaps something you need to have for your robots... Oh, voice recognition module is not actually required, you can just press a button on the robot. In this case, you can win a voice command module (I have 2 of them).

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Hi, I have just seen this compitition and am trying to complete an entry. I wanted to use the velcro collar method for picking up the bear, but have just realised I do not have any velcro. Would it be ok if i used 2 small magnets instead?

If not I will try to get some velcro in time for the dead line.




You're welcomed to participate! Use any method to catch/grab the toy and get it out of to safety.

Unfortunatly not able to make it, got to programming, was having problems with my arm and by the end of the night my robot was on the bench....in peices.

At this stage i wont have it ready by the end of the month due to a small problem of school, but have a break after from the 1st onwards and will complete my robot, and the task then even though their will be no prize, will be a challene for me programming wise.

However this being said it was great to see some one enter a robot for the competition, and the innovative way in which they collected the target, good job @sebathorus.

I feel as though i've let Robot-x down by registering my robot but not having it ready intime, but really i should be kicking my own ass that i had the opportunity to win some thing and futhure my robotics but i didn't get round to it!


Any ways, I've said my part, again good job sebathorus and hopefully there will be another competition along these lines soon when i can have my robot working and competing as i had planed.(and still do!)

Sorry to hear you can't make it. Here is the deal, I have 2 more prizes, for 2 more robots, who ever enters, wins them, no matter of the end date. If there are more than 2 entered by the end date, then we'll decide which of them is Second Place and Third Place. So, go ahead, finish your robot and enter it as soon as possible, you still have a chance to win something! I might through in more stuff in, I've got a bunch of unused things in my parts bin. Compass sensor, microcontrollers, motors, etc. You may win something just by participating.


Awesome, i'll give it a shot and get it done a soon as i can get some time to work on it. Hopefully get the mechanical part sorted out tomorrow afternoon. After that i just have to write the code, fingers crossed.

I see no reason to make a poll or have a comunity vote on this challenge at this time. Only one robot was entered by the end date, so I declare it winner of the First Place. Congratulations Sebathorus!

For the other people who expressed interest in participating, you have until the end of the month to finish up your robots. Hurry! I've got some kits to give!

Thanks to new deadline, I managed this weekend to bring my search&rescue robot to a working state.

The major problem was to find the object hidden inside the maze. 

First approach was to use 2 Sharp IR sensors mounted on left and right side of robot for navigate inside the maze and a home made senzor - 3 photoresistors + 4 high intensity LEDs for detecting the target. After many hours spent trying to differentiate the object (toy) from background (maze walls) I gave up on this method and choose a more straight one. Navigate the maze and grab anything could be grabbed, in this case, the toy.

So, I switch from gripper to a "device" (the only one came to my mind at 3:00 AM) "equipped" with a velcro collar, the other half of velcro were fitted to the toy. You'll see in the video and pictures what is about. The width of robot fitted with this thing is 26 cm.

Amazingly, I could not find in my daughter collection a teddy bear to fit my robot, so I pick a fairy, I hope is ok.

I build the maze from cardboard, the width of hallways is 36 cm, a little tight as I saw after programming phase began, but in the end was ok.

The search process works as follow:

- robot start navigating the maze and always keep on left side. In this time the "rotor" fitted with velcro is spinning continuously.

- when the toy is hit, the two half of velcro sticks togheter (not every time) and the toy is moved to the rear of robot where close a switch (the one used to start the robot). I hope this is visible on video, I plan anyway to record this process alone for a better view.

- after the switch is closed, the rotor is stopped, robot turns 180 deg. and swich from navigation to left side to navigation to right side and return to the entrance/exit. No path recording or processing is made, yet.

I will open a new node for this robot with pictures and details. 

Meantime, the video.



Too bad I could not get my bot ready, I guess we have a winner?

I am REALLY sorry about that, your bot look very nice and the way you made it is vey original.

I'm very curious about your and other peoples solutions to this challenge, I hope those who scratch their heads about how to solve this, will post here their solutions, finished or not.


... I got side tracked by playing with lasers and stuff ... I was close though when the batteries died on me, it wasn't slamming in the walls so much as before. Never really got to actually write the code to grab something, so I wasn't that close to finish before the dead line anyway. Lots to do, so little time as always:)