pic: Lego Robot for a F.I.R.S.T.-ish Game


This is the midway point for a lego machine I am building. It is being built to play a Game for Science Olympiad which is run through Gifted programs throughout the country as far as I know. I don’t have the exact specs on the game but chances are that the robot will have to fit in a 30 cm cube and score objects such as ping-pong balls and film canisters into a 30 cm cube. As seen it has 6 motors. 2 for drive 2 for the shoulder joint and 2 for the chain driven elbow. I plan to have at least one more motor for the sweeper brush to push the game objects into the hopper that will be mounted to the arm off of the elbow joint. I am not sure how many RCX’s I plan to use for this. I have yet to look up the maximum current output on one motor output. I will probably end up using more than one RCX just to get the added life, and oomph from the doubled battery capacity. I will post a picture of the finished product once I finish it. That shouldn’t be longer than a week.

i highly reccomend shortening your wheelbase or widening the track or using less grippy tires. you would have trouble turning iwth that setup. and i highly reccomend you learning how to use “Reinforcements” to make a stronger. more reliable robot with less weight. beam on beam on plate only works for so long.
and as for max amps from a rcx, do keep in mind its possible to use battery boxes and use an rcx to change the switches. doesnt drain the rcx batteries as fast either. have fun!

If the current setup does not turn as effeciantly as I would like it to with all of the final weight I am just going to take off the front tires rubber gripand be left with only the white hub touching the ground. I have already dabbled in this area and have no worries about it. Right now, I have a simple mock up on the front of the robot for lateral stabilization, it makes it easier to work on the base of the arm that way. When the final bot comes out it will not move wobbled/flex/ anything. I am going to build it like a true 222 machine; so I should be able to drop it from 8 feet in the air :stuck_out_tongue: . The weight is no issue. Right now I am actually planning to add weight blocks for a counter balance, but this is one of those test it when it is done things.

Also something you want to consider is if you want to run all of the motors independantly is that each rcx has 4 outputs, my idea of how ur planning on doing it would either require that second rcx, or run your brush off one of your other motor outputs, but that limits it a little bit, you probably knew all of this tho, just thought I’d make sure you did.

Each RCX only has 3 outputs actually. The only way I have figured yet of powering all of my motors is to put output in parallel from the CXs and run a single wire carrying the voltage for motors with the same task and re split the wires down at the bot to go the the individual motors. I think I am going ot use 2 homemade lego joysticks and push button limits for alll of the actual driving.

If you want two motors to run at the same time all the time, try putting them both on the same output port. If that doesn’t work, then link two RCX units somehow.

That will work I just want to make sure that I am getting the most power posssible to these motors which is why I am going to double outputs and then share inputs between the two (maybe three [hehehehe]) RCXs.

Thats amazing. My team is really behind right now. But, they have a GREAT mentor (Mat Temme) and I believe they can get it done in time. (I can’t help with programming, I help make the mechanical parts) Will this bot be at a FLL comp?

This robot will be competing in Robot Ramble, an event in Science Olympiad.

[off topic] You own the game pit! that is awesome! [/off topic]

Looks cool man, good luck in competition.