Primus Chassis

Now the motors are here and the brackets cut, it is time to assemble the bare boards to see what the mouse will look like.Primus is intentionally simple and consequently a bit chunky. Two large and two small boards are needed. These are conveniently cut from pieces of perforated prototyping…

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Sensor Data Analysis

Micromouse sensors are subject to several sources of error and interference. Capturing a set of data samples lets you do some simple analysis of the effects of those errors.The test rig was set up with a section of wall placed at about 50mm from the sensors. This gives a large…

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Sensor test

The simple sensor circuit described by Ng Beng Kiat seems to give the best results.On his web site (http://www.np.edu.sg/alpha/nbk/) Beng Kiat describes Min4, one of his recent mice. In there is a PDF with schematics for the mouse. The sensor circuit for Primus is essentially the same except for a…

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Motor driver chip

The Allegro SLA7062M stepper driver is a excellent choice for a versatile and robust stepper motor driver.This device will let you drive a unipolar stepper motor at voltages up to 46 Volts and 3A per phase. It employs an internal PWM control of motor current which is can be set…

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Motor Mounting

The Sanyo Denki 103H546 is a completely standard stepper motor in a size 17 frame. The mounting face is tapped with four conveniently located holes tapped for M3 screws.All we need is a simple way to fix the motor to the base and main circuit board. For that, some kind…

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Selecting the motors

For general ease of construction and simplicity for the new mouse builder, stepper motors are hard to beat. They are also generally large and heavy. A bit of a search soon turns up a variety of possible motors for Primus.Ideally, we would have a small motor to allow the construction…

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