Build your base robot
If you want to compete in the FLL competition, a robot is a must. If you want to score high points both on the field and in the robot design presentation, you need to build an efficient robot.
In this lesson, we'll teach you all the ins and outs of robot building!
When is a base robot good?
It is important that the weight of the base robot is balanced, so in our robot the hub is at the back and the 4 motors are at the front. It is advisable to place the rotation point of the robot in the middle.
Tip: Also make sure that your robot is horizontal, so that the attachments are not skewed.
Construction of our base robot
1 Lego Inventor hub
2 big motor, with which we move - these face the wheel
2 small motor, which face the attachments
We are deliberately not using sensors this year, as we have not seen any significant benefit from them in the navigation.
Our robot generations and developments
2023 Superpowered
simple robot with a single active attachment
⚡ can only accept one active element ⚡too small, does not turn reliably ⚡attachment receiver is too low ✅ moves successfully and easily
⮕⮕⮕
2024 Masterpiece
complex robot, 2x2 attachment receiver, with many metaphases
⚡not horizontal ⚡too many transitions, difficult to build the attachments ⚡wheel too far back, difficult to turn ✅ can accept attachments both front and back - although this was not needed in the end
⮕⮕⮕
2025 Submerged
developed in size and mobility
✅ turns ideally ✅ easily accepts the attachment, has stable rotation transfer ✅ sufficiently small, minimal unused part
The movement of the robot
A good robot is defined by its fast and precise movement. This is determined by the following aspects:
Wheel size and grip - After much experimentation, we chose 62.4x20 wheels for our robot because they grip well and are therefore more precise than the blue spike wheels
39367pb01, 56mm x 14mm
sBenefits:
✅ easy to install
✅ size to fit the base robot
Disadvantages:
⚡small grip surface
⚡wrong turn, slips
32057 / 32076, 70 x 14 mm
Benefits:
✅ medium grip surface
Disadvantages:
⚡size not suitable for base robot
⚡wrong turn, slips
86652 / 32019, 62.4 x 20 S mm
Benefits:
✅ large grip surface
✅ excellent turning and grip
Disadvantages:
⚡moderately buildable, fewer pins for the motor
⚡size that is difficult to fit on a basic robot
The center of mass of the robot - The mass of our robot is balanced because the hub is at the back and the motors are at the front
The robot's pivot point - We tried to center the pivot point of our robot for precise turning, it is 7 cm from the back, 4 cm from the front. The axle distance is 12 cm, which ensures stable turning.
Tip: If you are going to put casters on the robot, do not use spiked casters as they can get stuck easily. Use metal casters instead!
Make a plan for a Zombie apocalypse
You can use the Stud.io program to create images and animations of the robot.
This way, in the event of a zombie apocalypse, you can put your robot back together! 😀
📝 Task:
Make a basic robot, experiment, build it in Stud.io too! https://www.bricklink.com/v3/studio/main.page
Make a dumy robot
We often work at the robot table, even with 4 of us!
Unfortunately, we only have two complete robots, so we solved it by making a dummy robot.
We use this when someone is only involved in the construction and development of the add-on.
Benefits:
rapid progress in the development of attachments and problem solving
parallel work for several people at the same time!
Dummyrobot 1.0
Dummyrobot 2.0
📝 Task:
Make a dummy robot to progress more efficiently with your robot rounds!