When we first attempted to make a robotic bartender, we had an initial goal of making the product affordable for many. Obviously manufacturing efficiencies, and procurements savings could help save money, but our first prototypes were built using off-the shelf parts paying full retail costs. Similarly, if you’re thinking of designing or making your own automated bartender independent of Sir Mix A Bot, we’d thought we provide some price transparency into the cost of the components.
The Mechanical Parts of the Automated Bartender
To make the robotic bar, we needed a number of mechanical components. This includes the enclosure, the sliding drink assembly, the dispenser itself, and the drive motors and drive bearings. A complete price list and component summary is provided below.
8ft 2.5m GT2 Cable and small pulleys
|8mm Lead Screw Threaded Rod||1||5||5.000|
|Black Plastic Drag Chain Cable||1||4.29||4.290|
|GT2 36 or 60T large pulley||1||3.99||3.990|
LMK8UU 8mm Bearings
|8mm Linear Rails (300mm)||2||6.97||13.940|
Bar Dispensers (6 pack)
12mm x 1098mm shaft rails
|8mm Shaft Coupling||1||5.99||5.990|
12mm Shaft Beaings
|Steel Top Press||1||2.5||2.500|
Steel Bottom Press
Steel Bottom Ring
3d Printed Components
|6mm Birch Wood||19.66666667||$5.00||$98.33|
In total, the birch pieces, steel linear guides and other components would add up to a price of $296.41 before any electronics are added. Most of these parts are off-the shelf standard mechanical components, so we didn’t include brand names but rather specification names for these parts.
The Electronic Parts of the Automated Bartender
The electronics are listed below. In this case, we used many brand name and off-the shelf shields for micro-controllers and chips (e.g. we used the AdaFruit v2 Motor shield, Sparkfun Wifi Shield rather than purchasing the ESP8266 chip itself). This invariably raised the cost of the electronics set, but brought down the overall time to development.
|Arduino Mega 2560||1||6||6.00|
AdaFruit Motor Shield
SparkFun Wifi Shield
|RAMPS 1.4 Limit Switches||4||1.99||7.97|
|1602 LCD display and Keypad||1||6.99||6.99|
|NEMA 17 – 84 oz-in motor||2||11.87||23.74|
|N59 Infared Sensor||1||1.995||2.00|
|A3144 Hall Sensor||1||0.38||0.38|
|5/16″ X 1/8″ NB Magnet||5||0.0809||0.40|
How we bring down the costs of making an automated bar
Luckily, the total bar is far below the $400.00 + cost and there’s still enough room for us to make money. So how do we reduce the costs of the components to the robotic bartender?
(1) Buy in bulk to receive volume discounts
(2) Order components from low cost regions (12SBR rail is much cheaper from China)
(3) Eliminate the brand-name boards in favor of the electronic subcomponents (e.g. buying an ESP8266 chip saves almost 75% of the cost versus paying retail for a SparkFun 8266 board).