Ok.. it goes like this.
Info: This will be my first mini sumo robot. I have a basic understanding on how everything will hopefull
work but we would require some advice from a more experienced person.
We`re aiming at not spending very much money on it while also having a go at a decent performance
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Rules:
mass : 500g
dimensions : 100x100 base (milimeters), unrestricted height
Terrain:
Wodden disk like area. (magnets are forbidden and useless in this case)
77cm diameter . entirely black except a 2.5 cm circular white line on it`s edge.
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We have decided that the robot will be (90% certainty) 2 X wheeled with one wedge at the front and possibly additional wedges on the sides.
Picking the motor: We were stuck between pololu`s Micro Metal and 25D mm categories.
http://www.pololu.com/catalog/category/60 <= micro . 0.3 oz weight(~9 grams) , 24mm length
http://www.pololu.com/catalog/category/115 <= 25D mm . 3 oz weight(~ 90 grams) , 48 mm or larger length
Given the weight restriction I believe the best option would be the micro class since 2x25D would be about 200g and the accumulators would be about 200g as well .. not much left for ..anything.+25D would be hard to fit on a 100m width robot.
Major issue : we cannot decide how to balance out the Torque - RPM of these engines.
*RPM is at free-run , Torque at stall.
#1 : RPM:100, Torque: 70oz*in == 0.49 N*m
#2 : RPM:120, Torque: 60oz*in == 0.42 N*m
#3 : RPM:140, Torque: 50oz*in == 0.35 N*m
#4 : RPM:200, Torque: 40oz*in == 0.28 N*m
Wheels will be most likely custom made (we have the equipment for that) minimum diameter 30mm, maximum 40mm.
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Sensors:
4 x digital sensors : for detecting the enemy robot. we decided on digital because the distance to the enemy won`t help us very much and it would be a bit simpler to implement.
2 mounted on the wedge 1 on the left side 1 on the right side
sensor model : SHARP GP2Y0D340K. 40 cm range . we sacrificed a bit of range for the very good response time is has in comparison with the longer range models
4x floor sensors ( white/black). here we are in .. trouble . we dont really know a decent model found this one
Pololu QTR-1RC digital distance sensor . no idea how good it is for the task.
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So could anyone come up with a bit of advice
.. most importantly a good floor sensor
we really don`t want to fly off the ring without being pushed at least. would be completely embarrassing.