Let's Make Robots!

Cross the gap.

Winners as voted on by my family as follows below:


Game: Cross the gap.

Objective: Build an autonomous robot that starts completely within a 12 inch by 12 inch by 12 inch square box.

It must then cross a 12 inch gap and stop on the other side without any part of the robot touching the start side when done.

In order to win you must show a video of your robot completing this task, show the robot measurements and gap measurements in the video, and include the LMR logo on the video.

Fastest time to do so, and meet these constraints wins. Timing will start when the robot leaves the start box till its on the second table and not touching the start table. In the event of a tie, or controversy, public vote will decide a winner.


Prize for fastest completion goes to:   antonio.caciuc

  • Freescale 68HC11 microcontroller, 32KB Flash RAM, RS232 serial port programming interface, 2-line by 16-character LCD, Piezo buzzer for sound, 4x DC motor ports, 6x servo motor ports, 9x Digital inputs, 8x Digital outputs, 21x Analog inputs, w/ Interactive C software and code examples.
  • a pair of new metal gear motors
  • some assorted sensors - new unused.




Prize for the robot I find most interesting goes to: Kelpy (I was close to picking the NXT entry, but really liked the fabrication.)

  • A new Parallax Basic Stamp controller, product details can be found on their website, w/ software, cable, tiny breadboard.
  • 1 new unused servo, 1 used servo of same brand.
  • some assorted sensors - new unused.


Prize my family voted for most interesting:    sebathorus  (the first event entry)

What did you win? You will find out soon enough.



I am emailing the winners to send them their prizes. So winners check your inbox.


Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.

Sorry about the camera work, I was watching the motor spindle winding in the thread, and forgot the other end of the bridge :o

I wondered if anyone would pick up on old "HR". It's an expression I heard a lot when I was growing up, but not used much nowadays. I thought it was quite apt for describing my "contraption" :)

Its all good, your video and robot are great. I just couldn't tell exactly the timing, so I asked a relative for help. But I think we are within a second, so its not like its too big a deal.

(There's 3 members of my family who have posted using our 2 LMR logins)


I have a gut feeling theres a couple LMR members waiting to post their entries last minute, that will solve this in under 5 seconds.



(maybe 10, I'm not sure about 5)

I suspect the winner will be between 3 and 10 ;)

sneak preview

That looks very impressive, antonio.caciuc :)

I think I can see how it's going to work. Can't wait for the video.

It is actually not very good

The motor pushing the robot doesn't have enought torque so it stalls and vibrates and generally messes with the power and this makes the servo jerk around... it needs a bit of fiddling, maybe even a redesign...

This "robot" uses just two actuators: a servo to extend itself and a motor to drive forward.

I tried to make it look nice, but halfway through the build I just went wild with the glue gun and the wiring.

The motor I initially used was not well suited for the task so I replaced it with a modified servo. I also moved the batteries around a bit to put more weight on the drive wheel. Moving the battery pack also changed the center of gravity of the robot (which needs to be right in between the middle wheels) so I had to add 4 teaspoons to the front axle.


I am not completly sure if this qualifies as a successful crossing, so I am already working on an improved version. This one will have more than two actuators.

Wow, that's pretty fast. Simple yet effective.

Its started at :24, then is off the table at :33, so that's 9 SECONDS!!!


Wait, there's a controversy with this entry.

In order to win you must show a video of your robot completing this task, show the robot measurements and gap measurements in the video, and include the LMR logo on the video.


Can anyone beat 9 seconds?

The new one should be even faster and will even include the LMR logo :)