Circuitrocks

<r>Micromouse-style maze bot. Quadrature encoders on both wheels for position tracking. Straight-line: accurate. But after 10+ turns, position estimate drifts 5-10cm off actual.<br/>
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<B><s>[b]</s>Sources I identified:<e>[/b]</e></B>
<LIST><s>[list]</s>
<LI><s>[*]</s>Wheel slip on turns ...

<r>Class changed for next competition: 500g max instead of 1kg. Current bot is 850g. Surgery needed.<br/>
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<B><s>[b]</s>Weight breakdown:<e>[/b]</e></B>
<LIST><s>[list]</s>
<LI><s>[*]</s>Chassis (aluminum 3mm): 180g, biggest cut potential</LI>
<LI><s>[*]</s>Motors (2x N20 metal gear): 110g ...

<r>Sumo bot uses Sharp GP2Y0A21 for opponent detection. Bench test: solid 10-80cm range, predictable readings.<br/>
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Competition venue: bright LED ceiling lights. Sensor readings shift by ~15cm equivalent. Bot thinks opponent is closer than reality, drives off ring chasing ghosts.<br/>
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<r>Comp ended. Bot finished 3rd. Sharing what worked on PID after months of bench testing.<br/>
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<B><s>[b]</s>Starting point:<e>[/b]</e></B> Kp=20, Kd=0, Ki=0. Bot oscillates, can't track curves.<br/>
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<B><s>[b]</s>Final values that worked:<e>[/b]</e></B> Kp=14, Kd=380, Ki=0.05. Wheel ...

<t>Rebuilding after sumo loss. Stuck on motor choice.<br/>
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Brushed N20 12V 300rpm: torque ~0.5 kg-cm, life ~50hrs comp. Cheap, replaceable.<br/>
Coreless 1230 12V similar rpm: torque ~0.8 kg-cm, life ~30hrs. 5x spare cost.<br/>
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For 90s pushes coreless wins on paper. Anyone run coreless ...

<r>Rebuilding the sumo bot after the loss (other thread). One question I keep going back and forth on: brushed micro motors (cheap, replaceable) vs coreless (more torque per amp, lighter, expensive).<br/>
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Numbers I'm seeing:
<LIST><s>[list]</s>
<LI><s>[*]</s>Brushed N20 12V at 300rpm: torque ...

<r>Just back from a regional college sumo competition. Made it to semis pero nag-lose sa nakakahirap na rounds. Sharing what failed kasi maraming useful lessons.<br/>
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<B><s>[b]</s>The bot:<e>[/b]</e></B> 1.5kg, 4-wheel drive, 2x N20 metal-gear motors, IR sensors for opponent detection, IR ...

Late na ako pero hindi pa late: support sa RoboWars sa UP-NCR! Yung circuitrocks parating reliable sponsor for these events. Last year nag-set up din kami ng team, yung sumo arena setup hardcore.

Sino mag-aattend ng coming year edition? Bring na ko ng team.

Attending kami nito! Yung UP Circuit consistently good organizers pa naman. Sino dito sa forum balak attend? Pwede magkita-kita.

Yung last year SQUEEZE, may table na tinatakbo ng circuitrocks din ba? Nag-stop ako sa booth nila for components.

<t>Datasheet ng HC-SR04 sabi 4 meters max range, lab conditions yan I assume. For our outdoor obstacle course (sumo bot territory border detection), kelangan ko ng reliable detection at 2 meters minimum.<br/>
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May nag-test na ba ng HC-SR04 sa real outdoor conditions? Wind, surfaces of different ...