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10

Yes, you can buy all the electronic parts by themselves, but given that the electronic parts are the bulk of the cost, you may not save much. The MINDSTORMS EV3 set (MSRP $349.99 USD) contains: 1 - EV3 Intelligent Brick (MSRP $189.99 USD) 1 - EV3 Color Sensor (MSRP $39.99 USD) 1 - EV3 Infrared Sensor (MSRP $29.99 USD) 1 - EV3 Touch Sensor (MSRP $19.99 USD) ...


9

Here's a design I've been using, based on this model by Lambert Varias: It's not a perfect circle, but it is relatively small all things considered: It's pretty simple, but here's a partial disassembled version to better show what goes into it: Parts shown: 1x 55013 2x 4265c 2x 57585 6x 32013 6x 32556 12x 42610 12x 50945


8

I have copied a design by Isogawa Yoshihito I prefer it over the Lambert Varias design as the wheels are positioned more radially More pictures in this EuroBricks thread: https://www.eurobricks.com/forum/index.php?/forums/topic/76297-isogawayoshihitos-lego-technic-omni-wheel-crab/


7

This is actually a surprisingly difficult task. If you search for similar questions over on the Robotics stack exchange, you will find very smart people who can't even get it right with thousand-dollar localization solutions and graduate-level control theory. If you have a Gyro sensor like Michael suggested, you're on the right track. You can probably get ...


7

This seems pretty much bordering on the impossible, given the current state of (LEGO) engineering capabilities. What you are describing is a Von Neumann Machine and as far as I know nobody succeeded in creating one, not just in LEGO but in general. The problems you'd have to overcome: The robot must be capable to exert sufficient force to overcome the ...


5

It looks like the page listing downloads is down, but direct links to the downloads still work. I believe that this is the file that you're looking for: https://www.hitechnic.com/upload/306-Color%20Sensor%20V2.zip


5

Just stumbled across this little gem of a Lego omni wheel!


5

Hmm... I don't know... I personally, wouldn't try to reinvent pin placement of Technic holes and Studs. I'm not saying being creative that way is too challenging. What I am saying is that, we should work with examples, or in this case parts that already bridge Classic stud width with Technic holes. Placing pins where the studs belong seems akin to ...


5

This part is called Micro Scout with Dark Gray Base the white version on your photo comes from 9748-1: Droid Developer Kit (pictures via Bricklink)


4

The RCX system provides a certain average voltage level (via PWM) to the motors. This means that speed can vary based on load, and may even vary slightly from motor to motor. Power will also vary based on load, as a motor with more load will draw more current if voltage is held constant. If you're interested in specifics, you can measure the voltage and ...


4

This formula will need the lateral distance between wheels, i.e. the distance between left and right wheel, not the back and front wheel. motor_pair.move(8.1 * math.pi / 2, 'cm', steering=100) The steering=100 parameter means that the wheels will move in opposite directions. For the 8.1 value, one wheel will move +12.7cm and the other wheel will move -12....


4

It is possible to communicate between the 31313 and 51515 hubs. See these youtube videos: https://www.youtube.com/watch?v=PT4_4v1W2C8 https://www.youtube.com/watch?v=p3uk80tuqI4 In the first video a SPIKE Prime hub (same as 51515 just different firmware) is used to control a 31313 hub and in the second video there's more of explanation of how it's done. I do ...


3

What if you had anti-studs where you want them, at stud-depth, but also overlaid technic holes at full technic pin depth where you want them? This would lead to a complicated, non-standard arrangement, but if you look at, eg, the new 2x1 jumper plates, they are designed to allow a stud in the middle between the two normal anti-studs. Since you have two ...


3

The .UF2 file format appears to be a fairly compact, binary format for reliably transferring data to "microcontrollers" (i.e. small embedded systems such as the EV3 controller), and is the format used by the Microsoft MakeCode application, recommended as part of the First LEGO League. The .ev3 file is actually a zip file containing a number of additional ...


3

Your question is not so clear, but it seems like you want to build robots and you want Technic pieces. Then Lego Mindstorms is the product you should buy. While not formally part of the Technic range, it contains only Technic elements in addition to the special electronic Mindstorms parts. You can also take a look at Lego BOOST, a lightweight variant of ...


3

Do you have a gyro sensor on your robot? I'm assuming you're using an EV3 set, and the Mindstorms programming environment. If so, reset your gyro sensor, and then insert a loop block attached to the gyro sensor. Set the loop settings to >= 16 degrees, and insert a tank move block into the loop. The motor should be set to 'on', with wheels going in opposite ...


2

If you are using the EV3 Sensors you should use the EV3 Color Sensor which can detect 8 colors (colorless, black, blue, green, yellow, red, white and brown). If you are using the NXT I would recommend the HiTechnic Color Sensor or HiTechnic Color Sensor V2... I hope I could help.


2

Another option is to use LOTS of 60483 Technic, Liftarm 1 x 2 Thick with Pin Hole and Axle Hole as shown in: https://youtu.be/X89pXBJaPWI?t=7s


2

Use your gyroscope sensor, set your program to have the Move Tank block turn very slowly in the "On" mode, and then use a Wait block checking the Gyro sensor until it sees an absolute change of 90 degrees. Then add a Move Tank "Off" block. That's the closest you will come to 90 degrees.


2

For moving on defined path you can achieve amazing accuracy with LEGO MINDSTORMS EV3 odometry combined with good gyroscope but this still will result in a collision sooner or later. Examples of such systems can be found here and here Both of these systems use MICROINFINITY CruizCore XG1300L gyro/accelerometer but there are other good gyroscopes. The only ...


2

An option that comes to mind is building a Raspberry Pi-based robot. But it's not likely to be small nor easy to put together, code and all. I think going for a LEGO robot would be easiest; motors, electronics and power source have all been taken care of. You "only" need to connect them and program the EV3 brick. There are numerous YouTube videos of ...


2

The ultrasonic sensor is useful for navigation. This robot design has a nice skirt and positioning the ultrasonic sensor should not interfere with that skirt. Also the ultrasonic sensor is excellent at detecting right angles like the floor meeting a wall. So, I'd recommend positioning the sensor on either a side (for following along a wall) or the back (...


1

If you want the belts to operating in a single plane, you could try having an angled blockage across the corner which diverts the blocks onto the next belt, like this. If you don't mind them going slightly up hill then all you need to do is make the one it is dropping off finish up high and have the next one be underneath it. In your diagram the dark green ...


1

It's easy to use Lego Mindstorms EV3 to build small robots. There are competitions such as the WRO where EV3 soccer bots compete. Sensors like IR seekers from HiTechnic are used to detect the "football" which is an IR emitting ball. As for a warrior, it is hard to balance Lego robots to make something which can walk but you could make the warrior run on ...


1

I built a walking machine when I was a kid several (cough) decades ago, and it had a similar problem. We finally figured out that what I had built was very front-heavy. Weight has to be balanced equally, forward and backward, over the "hips" of the creation. Pick up the creature by the top of the hips and see which way it swings. I solved the problem by ...


1

Without solving your homework, you will need at least the following blocks: for bullet 1 Light Sensor Data to Text LCD Panel Display for bullets 2 and 3 Loop (forever) Switch (based on light sensor readings) Motor Block (4 of these, 2 for > 50% + 2 for <= 50%) And it probably makes sense to put bullet 1 inside the loop of bullets 2 and 3.


1

You could use worm gears, or worm gears, or compound worm gears, because you can slow the rotation down as much as you want, which means you can have super fine rotation. An extreme example of this would be the 120 years timer here This uses a compound worm gear and spur gear train. Worm gears also have a lot of torque in a small space. if you want the ...


1

The motor speed is controlled by time modulating the available voltage (approximately 9 volts). So at 100% it looks like a continuous 9 volts. At 50% it is periods of 9 volts and 0 volts in equal amounts. Something like 100 time blocks per second.


1

Could be the button indeed. These buttons are conductive rubber pressing on the circuit boards integrated contacts. Might need some cleaning there... Disassembly of the RCX is not easy but can be done. You have to remove the screws in the battery compartment, then pull slightly to disengage and remove the black IR front. Once this is done, you can pull out ...


1

Updating the iOS version to 10.10.5 seems to have solved the problem for me. Hopefully this helps someone else out there.


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