For convenience or pageantry, a drink-bot is a great addition to the next big get-together. That is why I built the Drinkmotizer, an Arduino and Raspberry Pi packed party-fueler.
The version I built is four feet long. It can hold up to 16 bottles and has a chaser station at the end. The cup platform movement is derived from my experience with industrial CNC lathes. In the video below, you can see that I have a 2-start 4-TPI leadscrew doing all the movement. The stepper motor I used was in the 90-oz/inch range. If I changed the stepper motor out with something more powerful, I could move it much faster. The little stepper I used tried really hard, but at higher speeds it had a tendency to slip due to friction of the coupler nut.
This is a full shot of the Drinkmotizer from the stepper motor side.
I was asked, “Why not use pressure for all the bottles?” and “There are other bar-bots that spray drinks out to a single spot, so why do I want Drinkmotizer?”
It’s simple, bottles are classy. Ask yourself, would James Bond get a drink from a glorified self-serve soda machine? I wanted to keep the liquors in their original bottles. I also wanted to see the liquid pour out and the bubbles rise.
Aesthetically speaking, it's fun to watch the drink move down the line gathering its components. With a little Raspberry Pi and Arduino know-how, and a few power tools, anyone can build a Drinkmotizer of his or her own. At least that was my supreme goal behind it all. If you have trouble or need parts, let us know in the comments section below.
Wow, impressive, Chuck! I feel humbled in the presence of such talented folks, coming more from a journalist/writer side of things than the engineering side. I do have a fascination with technology and innovation, though, so I suppose that helps. Even if I can't do it, I can at least admire it and write about it. I think if other staff members are developing cool things, they should speak up and write about it!
We've had some pretty amazing people on the staff over the years, Liz. Jon Titus, who retired from Design News only a few months ago, is actually credited with building one of the first PCs, the Mark-8 in 1974, which appeared on the cover of Radio Electronics (unfortunately not on the cover of Design News). It's now on display at the Smithsonian Intitution in Washington D.C., which gives an idea of its monumental significance. That said, I don't remember any of our staff editors writing an article in DN about their own invention. To my knowledge, Cabe is the first.
I was wondering about that, Chuck. I haven't been around Design News that long but I was also wondering if it was common for an editor to also be an inventor and write about his/her own work. I think it's really interesting and cool, but personally I can only write about engineering, not actually invent anything or do anything too technical! So this makes me extra impressed about what Cabe has done. But perhaps we should do more of this if there are equally inventive people on the writing staff.
78R, You propose an interesting alternative. But the problem of stepper motors slipping steps happens much more at higher speeds, rather than at starts, as long as the load is within the ability of the motor. So the control could be quite simple, just to add the additional torque whenever the velocity command exceeded some value. No need for a high level of control there. And another option would be to raise the stepper motor voltage when the speed command went above some setpoint. That would be a lot simppler mechanically and probably only require adding either a single relay or a switching transistor. And the voltage controller could be driven by the velocity command amplitude, so there would be no extra computer control functions involved. That is about as simple as I can think of.
Excellent comments, William K. Cabe does walk the walk and talk the talk of a design engineer.
Building on your idea of torque assist for the servo: Adding a brush-type DC motor would make the State Machine more complex and would likely require multitasking to control two types of motors and monitor position, suggesting an RTOS. Thus, the Raspberry Pi would take on this burden, not the Arduino. What do you think about providing torque assist via a latch solenoid engaging a twist spring just before activating a servo? There could be one spring for forward assist and another for reverse assist. The torque would be just enough to supplement the servo's effort. This might be a simpler approach, though I haven't thought through how to rewind the spring.
Some humanoid walking robots are also good at running, balancing, and coordinated movements in group settings. Several of our sports robots have won regional or worldwide acclaim in the RoboCup soccer World Cup, or FIRST Robotics competitions. Others include the world's first hockey-playing robot and a trash-talking Scrabble player.
A recent example of a major CAE revamp is MSC Apex, released last month by MSC Software Corp. In a discussion with Design News, MSC executives noted that its next-generation platform is designed to substantially reduce CAE modeling and process time, “in some cases from weeks down to hours.”
The Thames Deckway would run for eight miles close to the river’s edge, rising and falling slightly with the tidal cycle. It will generate its own energy from a series of devices that will line the pathway and use a combination of sources to make the path self-sustaining.
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