Modified servos

This time I have upgraded to metal geared servos however they are still locked to +/- 90 degees and so they need modifying for continuous rotation.

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Here I am using 2.2k ohm 0.1% tolerance smt resistors to replace the potentiometer and trick the servo into thinking it’s locked in one postion.

IMG_20160219_165915 (Medium)Last time I used some random through hole resistors I had lying around and when it came to trimming the servos there was a lot of drift, far more than I could correct for, so this shall be a big improvement.

IMG_20160219_173252 (Medium)Tiny!

Thoughts on robot wars

Well that’s my 1st robot wars competition over and done with and I can say I have much to improve on !

Movement – Servos modified for 360 degree rotation have lots of drift and thus slowly rotate when you want it to happen least. Use proper servos or motors and drivers.

Battery life – 300 mAh batteries are fine but excess weapon motor useage will deplete them. Locate the charging port to somewhere that’s easy to access for charging between rounds.

Amour – All cables *must* be projected from cut damage or you risk losing the round early as the green machine experienced.

Overall though I felt I did alright and got through to the 3rd round.

Video recording of the event by BEEES

Servo modification

This post is a few pictures showing the modification of SG90 servos so that they rotate 360 degrees rarther than the standard 180 left/right.

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Bottom casing removed and you can see the control board, motor and potentiometer.

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Here is the servo with the top half of casing removed. One of the gears has a pin that physically stops full 360 degree rotation so that must be cut off.

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Small pile of gears and drive shafts.

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My first attempt at soldering a pair of resistors in place where the potentiometer previous connected to. This is to trick the control board into believing it has not rotated far enough yet.

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2nd attempt on the other servo, space is very limited when you put the end casings back on so you really need to shorten the resistor legs as much as possible.

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And back together ready to act as drive motors for my robot.

Robot Wars Inspiration

When I used to watch the 1st series of robot wars I always planned to emulate ‘Roadblock’ as its simple shape and mechanics seemed easiset for me to recreate at home. Since I was in school then, that never really took off but now I have the money and equipment to make an ant-weight hommage to ‘Roadblock’ for the BEEES robot wars.

Here is a link to the wiki where you can find out about ‘Roadblock’s various wins.

http://robotwars.wikia.com/wiki/Roadblock

Robot Wars

Well it’s the start of the new term and so that means BEEES will be hosting it’s robot wars competition. Inspired by last years tournament I’ve decided to enter myself and on this page you can see my progress.