BreadBeast: A Breakout Board that turns Breadboards into Robots. - Page 1
Forum section: electronics / general

author: PioteLLC
author_rank: Contributor
timestamp: June 03, 2016, 02:17:59 am
content: Hi EEVBlog!We're Mark and Steven, creators of BreadBro (www.breadbro.com). We created BreadBro to integrate Breadboards and Development Boards.BreadBro is Open Source, and once BreadBeast is in a releasable form, it'll be Open Source as well.The general idea is that you stick a BreadBeast onto each end of a breadboard, wire it up to a microcontroller, and bam! Breadboard is now Robot.The current BreadBeast prototype is a breakout board that spans both sides of a breadboard. The breakout interfaces with the breadboard through twelve “Dead” header pins – they're only structural, not electrically active. The breakout spans the width of the breadboard and then some, overhanging by about an inch. Underneath each overhang, a DC Gearmotor is mounted using zipties and three beads of hot glue.Blog post on our site with more information:http://www.breadbro.com/blog/2016/6/1/introducing-breadbeastImgur Album:http://imgur.com/a/Y2L8qThe current prototype has a layout that allows placement of a TB6612FNG Dual Motor Driver and some capacitors. However, we already know we need more, so the prototypes are being used structurally more than anything else right now.We're trying to figure out how to minimize the number of pins required to communicate with two motors. The TB6612FNG requires 5 digital inputs and 2 PWM inputs from whatever is controlling it. By our experience, minimizing pins means multiplexing. However, we want full control over communications between the user and the motors, so we've decided to use an ATTiny84 to control the motor driver. Basically, an Uno uses Software Serial to communicate with an ATTiny, which in turn controls the motor driver.On the power side of things, we want an onboard power supply. That way, the breakouts only need to be installed and connected to operate. We're leaning towards onboard LiPo batteries with USB charging (MCP73831 controller) and 5V output (NCP1402 boost regulator) for powering a nano, micro, photon, teensy, or whichever other breadboard-compatible development board a user prefers. In testing, this seems to work okay - the gearmotors (298:1) are quite happy with 2.8-4.2V, and they have a good bit of torque, too. This is just the scheme we're leaning towards, though - the power supply may end up being very different, and we'd love your input!Our hope is to iterate another one or three versions, and run a Kickstarter to help fund an initial bulk purchase of the most expensive component - the gearmotors. We're shooting for a price point of about $40-80 USD for a set of two (You need two). Hopefully it's on the lower end of that, but as long as we're in the ballpark of other small robot chassis kits, we're probably going to push through to production.Any and all thoughts, suggestions, and opinions are really welcome! We're building BreadBeast for the Open Source Hardware community, so we want you to be a part of its design!Regards,Steven & Mark

author: VoidsWarranties
author_rank: Contributor
timestamp: August 20, 2016, 02:24:33 am
content: Great idea one of the things that would be nice is current sensing and/or some feedback from the motors. The lipo or lion battery would be awesome to have built in. would it be 1 lipo on each board. And lipos can be dangerous if over discharged, would It have a protection circuit or voltage feedback to the arduino?Sent from my iPhone using Tapatalk

author: ez24
author_rank: Super Contributor
timestamp: August 20, 2016, 03:33:11 am
content: Surprised the the original post was Jun 2 and only one reply (now two). Good idea.I suggest 18650 batteries in spring battery holders with the ability to recharge in place (with a wall wart) or replacing batteries like they were AAs.I have a LED headlight that uses this method and I like the flexibility to recharge. There are a lot of 18650 stuff out there.