BarBot/Components/Makerslide and Platform

Makerslide and platform

General Description

The 24 RGB Neopixel ring illuminated drinks platform glides along awesome Makerslide!

The platform is moved by a NEMA17 Stepper Motor, 1.8° per step, 1.7 A, 4000 g·cm stepper motor driven by a Pololu stepper driver. The AccelStepper library is used to control the stepper. One cm travel is approx 55 steps.

An ultrasonic sensor is used to detect the presence of a glass. This provides a signal to a local ATtiny85 in the platform, which in turn controls the Neopixel LEDs and provides a "glass present" signal to the master Arduino.

The left hand end of the Makerslide has a limit switch. This should be used to "zero" the stepper on each cycle.

BarBot Makerslide and platform

Notes:

• Not sure whether the ultrasonic sensor will be affected by spills and splashes.
• To prevent overheating of the Pololu driver and/or stepper motor, it is recommended that the stepper driver is disabled whenever the platform is stationary. (However, this does present a risk of not knowing the position if it should be knocked whilst disabled.)

Mounting & hardware

T-slot nuts are used to invisibly (and very nicely) mount the Makerslide.

Logical

The Pololu driver needs three Arduino digital outputs: Enable, Step, Direction

The ATtiny85 in the platform provides a "glass present" signal. (0 = no glass, 1 = glass present)

A further "mode" signal is used to select ultrasonic diagnostic mode (if low when power applied), or over-ride the ultrasonic sensor (if low during normal mode).

Connections

Wire colour	9 way D pin	Signal
Orange	1	+5V supply to ATtiny85 and Neopixel ring
Red	2	Stepper coil B
Blue	3	Stepper coil B
Green	4	Stepper coil A
Black	5	Stepper coil A
Yellow	6	Diagnostics / ultrasonic over-ride "mode" input
White	8	"Glass present" output
Brown	9	Ground

Power

• Stepper motor / Pololu driver: +12V, TBC mA
• ATtiny85 / Neopixel ring: +5V, TBC mA

Bling

An awesome 24 RGB LED Neopixel ring!