How It Started...Part of the requirement for this course required the design and assembly of a robot.This robot was then required to find its way through a maze using nothing but ultrasonic sensors to guide it through the maze.The parts required was:(1)Gearbox with drive motors,(2)Front Wheel,(3)Ultrasonic Sensors x3,(4)Picaxe,(5)Battery Holders x2.(6)Robot Base.I decided to assemble the gearbox first to give me an idea of what dimensions to give the robot.Width,length,etc.These dimensions helped me decide on what size to make the Base.This was made using a CNC .Firstly, i dimensioned and designed the base.Then,using these details,i used the CNC to cut the base out of a piece of clear plastic.I was then able to mount the Gearbox assembly and the front Castor Wheel (Thanks To J K )to the base.No real problem there.Then the picaxe was mounted.I utilised long screws to do this as i could easily raise the picaxe to an ideal height.I then neede to fabricate two brackets to mount the Battery Holders into place.I wanted to have the Holders mounted securely.I also fabricated a pair of wheel Arch Covers.These had two things to do.One was to cover the wheels.And two,to be used as a base for the side Ultrasonic Sensors.I fabricated another bracket to mount the front Sensor.Whilst assembling theses items there was the usual small hassles associated with designing and using items.Needing small alterations and adjutments as assembly and testing happenned. Originally i decided to use 115:1 as the ratio for my robot.But while i was programming it,i felt that it might have been going too fast for the sensors to pilot it.So,i then decided to change the gearing to 344:1.I felt that the speed the robot was now going would be fine for the sensors to pilot the robot through the maze.Changing the ratio required that i move the whole gearbox backwards as the axle shafts were now coming out of the gearbox housing at a different point.Two new holes were drilled and that was it.I mounted the Sensors above the Drive Wheels.I felt this would be beneficial as the turning point for the robot was at the wheels.When turning,one wheel stops while the other turns.Programming the robot was something that took longer than expected.My robot had the added bonus of having two motors that were different in performance.One was faster then the other.This required a modification to the programming.A compromise was eventually found where the robot went through the maze without any problems.When i first started running the robot i found that it would work using only one Battery Box(3 AA Batteries-4.5V).So i spent a little time programming the robot to work with one power supply(And aslo used up alot of batteries).I eventually found that driving and guiding the robot took it's toll on the batteries.This would in turn effect the performance of the sensors.So,i decided to utilize the second Battery Box.One power supply would be dedicated to the drive of the robot.While the other power supply would only power the Picaxe and sensors.This extended the life of the batteries and helped the robot work more efficiently. 

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