Robot Design.

Transcription

1 Robot Design Michael Hartwig

2 Agenda 2016 KC Region robots Design Elements and Process Robot Design Attachment Design Missions Demonstration Resources Questions 9/9/ KC FLL Coaches Training 2

3 2016 Results Statistics from qualifying tournaments & the regional championship 9/9/ KC FLL Coaches Training 3

4 Design Factors Mindstorms are not high precision devices Sensor accuracy & tolerances Motor & other gear train slippage Limitations of LEGO construction 2.5 minutes is a short period of time Time spent in base is time not scoring Time spent driving to missions is time not scoring Tables & models are not all the same Self-aligning vs. jigs or manual line-up How exactly, repeatablycan a robot be set up? Wall following Sensors vs. odometry 9/9/ KC FLL Coaches Training 4

5 Design Process Start simple Don t let kids go beyond their capabilities Need to understand what they re creating & how it works Plan before building & programming Kids need to experiment Formalize, and record results Don t allow guess and retry No assumptions test & compare variations Design for failure Robots need to succeed despite inaccuracies and onfield problems 9/9/ KC FLL Coaches Training 5

6 Construction Build solid robots: Don t rely on single pegs to join beams use L beams to join angles or short beams to splice 2 long beams I love the 3-long 2-peg + axle socket pins for attachments. Don't come out and therefore don t have to be removed. Align & position sensors correctly Color / light not too close or too far from mat; completely perpendicular. Touch sensors position or build so triggering doesn t move the robot Ultrasonic make sure they re below the top of the surface being detected, and perpendicular Team needs to check robot connections regularly - make sure it's staying together. 9/9/ KC FLL Coaches Training 6

7 Coaching Main job is to inspire Create an environment for success Help the kids learn the rules Need to solve the right problems Rely on themselves Make the game environment realistic Timed practices, with scoring Combine with other teams & have practice sessions Attend rumbles if at all possible; especially rookie teams Help team set realistic goals They ll feel more accomplishment reaching small goals then failing at big ones. Start with a small # of missions as a goal; the team can always add more if they finish the original goal. 9/9/ KC FLL Coaches Training 7

8 Robots - Custom 9/9/ KC FLL Coaches Training 8

9 Robots Kitbots & mods 9/9/ KC FLL Coaches Training 9

10 Robots Quick-change attachments 9/9/ KC FLL Coaches Training 10

11 Robots Passive attachments 9/9/ KC FLL Coaches Training 11

12 Robots Base organization 9/9/ KC FLL Coaches Training 12

13 Mission Demonstration 9/9/ KC FLL Coaches Training 13

14 Resources FLL web site: FLL forums: EV3Lessons: TechBrick: Books: FIRST LEGO League: The Unofficial Guide - Guide/dp/ Winning Design!: LEGO Mindstorms EV3 Design Patterns for Fun and Competition- MINDSTORMS-Patterns- Competition/dp/ /ref=pd_sim_14_6?_encoding=UT F8&psc=1&refRID=57EBR5VZ9M3VCRDXHP4R 9/9/ KC FLL Coaches Training 14

15 Questions? 9/9/ KC FLL Coaches Training 15

16 Supplemental Info on Construction Slides from Team Titanium summer camps 9/9/ KC FLL Coaches Training 16

17 Joining beams

18 Building robots that go straight -1 Don t let the middle of your robot sag Support your wheels on both sides Don t make the supports too far from the wheels Notice beam on the Notice beam on the outside of the wheels

19 Building robots that go straight -2 Make sure your tires are fully on the wheels

20 Building robots that go straight -3 Remove any gear slack before you start the robot The gears inside the motors have a little bit of play If you make sure that both are ready to engage when you start, the robot won t curve before straightening out Do this by pulling back gently until neither wheel turns

21 Don t let your robot get caught up on Things sticking out from your robot can get caught on missions Most often it s cables Some solid parts can also get caught, like pushers Cables sticking out can also affect your ability to start your robot totally inside base. table missions

22 More consistent sensors light and color Point the sensor straight up & down tilting it can change readings. Sensor should be about 1 cm from the mat. Ambient lighting (the light already in the room) can affect your light sensors Lights may be different at your practice table than at a tournament, or even between different tables in the same location Lighting may change during the day Two ways you can help minimize this problem: Build your robots so that the sensor is shielded Calibrate your sensor

23 Shielding light and color sensors Minimize the light that gets to the sensor by building around it Build a box Put the sensor as far underneath your robot as you can & still be able to find what you want to. This way, only the light coming from the sensor gets read.

24 One way to shield a sensor

25 More consistent sensors ultrasonic and touch Ultrasonic: Usually should be mounted horizontally; tilting the sensor can affect results Mount low enough to locate the wall. For FLL make sure you know the rules for wall height Touch: Mounting off center can make the robot twist as the sensor triggers Attach parts to the sensor so that it will hit the intended target

26 Building attachments that can be changed quickly A FLL match is only 2 minutes and 30 seconds long. The less time you stay in base, the more time your robot has to do missions One part of quick turnaround is getting to the next program quickly The second part is getting attachments on & off Build your robot so that it has a standard way to attach things Build all of your attachments so they attach to the robot the same way Build your attachments so they do more than one mission, so you don t need to change them as often.