Robot Design Hardware

Transcription

1 NanoGiants Academy e.v. Robot Design Hardware 2017 NanoGiants Academy e.v. 1

2 This Presentation is one of four about FLL Robot Design Hardware Navigation Software Strategy NanoGiants Academy e.v. 2

3 Requirements from FLL robot game and implementation with hardware Agility Stability Precision Reduce stress Avoid risks Maintainability Easy to extend Caster wheel does not rip off Transport in not a problem EV3 used as a handle Smooth front and sides Back build to adjust with table walls Axels supported Minimal width, length, height Position of color sensor Position of gyro sensor Display towards driver Cables inside Battery socket easy to reach Fast, reliable change of tools Improved development process Robust Construction External Frame Vehicle Geometry EV3 and Cables Modular Tools 2017 NanoGiants Academy e.v. 3

4 All requirements can be fulfilled with one Education core set The photos in this presentation show a robot implementing all concepts discussed, although it is build from a single LEGO MINDSTORMS EV3 core set (45544). However, there are not too many parts left to build additional tool modules. We decided against publishing the building instructions. This presentation is meant to provide impulses, not perfect solutions. If more parts are available, many things could of course be done even better. Some related ideas can be found at the end of the presentation NanoGiants Academy e.v. 4

5 No wobble. No loose parts. The brick is a handle. Robust Construction Additional lift arms ensure right-angled connections and prevent that others get loose. To ensure the caster wheel cannot be ripped-of, it needs to be integrated, not just inserted from the back. Only if the EV3 brick is firmly connected, it can also be used as a handle NanoGiants Academy e.v. 5

6 Reduced risk. Improved navigation. Precise Traction. External Frame Smooth front and sides shielding the wheels prevent the robot to get stuck at models. Alignment with table walls requires a solid, smooth back. Cables must not get in the way. If the motor axles are supported on the outside, they cannot bend. Distance between wheels is fixed NanoGiants Academy e.v. 6

7 Compact format and sensors at the best positions Vehicle Geometry Compact robots need less space to turn and have less issues with narrow passages. For effective use, the color sensor should be centered and in front of the wheels. Distance to mat is crucial. Putting the gyro sensor between the motors instead somewhere on top avoids cable spaghetti. Dimensions of the bot shown (tool excluded): Width: 19 Motors, wheels, and shielding / axle support Length: 22 color sensor before wheels, tool motor, caster wheel, and sufficient room for cables on the back Height: 16,5 Wheels, motors, room for cables, and EV3 brick with battery Distance: 1 to 1,5 brick units For an example of an EV3 minimal core see NanoGiants Academy e.v. 7

8 Make the EV3 brick part of the robot by design EV3 and Cables Display in driving direction reduces driver s stress when launching from base. All cables inside between motors and EV3 prevents that cable loops get tangled with models or plugs get pulled. Battery plug accessible and LEDs visible allows to charge without taking the robot apart NanoGiants Academy e.v. 8

9 Modular tool are great for FLL robot game; important for development Modular Tools Modular tools reduce retooling time in robot game to seconds. To build modular tools, the interface needs to be defined once and must not be changed later. Tools can be build and improved without modifying the robot. Several team members can work on different tool modules in parallel NanoGiants Academy e.v. 9

10 Ideas to improve further, if more parts are available Two tool motors instead only one One at the front, the other at the back? Or both side-by-side? Modules using a single motor each? Or modules connecting to both motors? Add more color sensors In any case keep one for line following (centered and in front of the wheels). Additional ones at front or back allow to detect crossing lines more easily. Two color sensors side-by-side (but with significant distance between them) allows to align square to a line. One gyro sensor is sufficient Invent new interfaces for tool modules end test them Using other parts then those from the Education core set can lead to significantly more effective interfaces. Talking to experienced teams or asking Google helps. Build and test many different tool modules If a tool module works ok, set it aside and build another using a different approach. Only then decide which is better and improve that one further. The whole team can get creative here. Shield the color sensors EV3 is already rather ignorant of additional sources of light. Nonetheless, shielding the sensors can be beneficial. Test: If the robot is placed on the mat and light emitted from the sensor can be seen, stray light will also reach the sensor NanoGiants Academy e.v. 10

11 Contact and further information Mail: Web: Facebook: YouTube: Heinz 2017 NanoGiants Academy e.v. 11