FINAL FEW HOURS! Take a look at the updates - we will start shipping ControLeo this month :-).
Relaunched with lower funding goal and simplified rewards. We are able to lower the funding goal because we've already secured most of the components needed to manufacture ControLeo.
The idea behind ControLeo
Arduino is a fantastic platform, very easy to program and with excellent hardware support. If you don't need to interact with the finished project, you can buy an off-the-shelf box and shove the mess of wires and boards into it. But what if you need to interact with your project?
We wanted to build our own reflow oven. The oven would be used about once every 2 weeks so we could prototype the next board. We wanted a LCD screen, buttons and indicator LEDs to show which of the oven elements were on at any given time. But most importantly, we wanted a robust, good looking box for this project that covered all the exposed wiring and connections.
We love the flexibility of Arduino, and take that to heart. We made ControLeo as generic as possible so that it could be used for a variety of projects. We think it is awesome as a reflow/pottery oven controller, but it can also be used to control sprinkler systems, lights, motors and more. We're looking forward to hearing about the things you plan to use ControLeo for!
What is ControLeo?
We took the Arduino Leonardo as a starting point for this project, and added:
- 4 relay outputs with red indicator LEDs
- LCD display (2-line x 16-character)
- 2 buttons
- Real-time clock (optional)
- MAX31855 for reading temperatures (optional)
- I2C GPIO chip to free up digital I/O on Leonardo
- A solid, custom-fit ABS plastic case
The result is beautiful programmable controller you can use for your projects.
The philosophy behind ControLeo
There were three main thoughts that drove us as we designed and prototyped ControLeo.
- Open - We wanted to put as much of our design and software into the public domain. To that end we have already posted our schematic and source code to GitHub.
- Flexible - Our driving desire was to make ControLeo as flexible as possible to accommodate a wide a range of projects. We freed up digital pins by using a secondary chip to drive the LCD display and then we exposed all unused digital and analog pins in an easy-to-use header.
- Robust - We wanted ControLeo to last a long time - even in inexperienced hands - so we did things like up-rate connectors and add reverse polarity protection.
ControLeo is open
Our schematic for ControLeo is in the public domain, and has already been posted to GitHub.
The software for ControLeo consists of a single Arduino library that controls all of ControLeo's functions. We've also included 14 sample programs to help you get up and running quickly. We've already posted all our software to GitHub too. You can start writing your program today!
The source code has been released under the WTFPL license, which quite literally means "You just DO WHAT THE F!#@ YOU WANT TO.". We've had fun working on the hardware and software and would like to see ControLeo used without restrictions.
ControLeo is expandable
ControLeo provides both 5V and 3.3V supplies to power additional components. There are 7 pins available for digital I/O (4 with PWM) and 5 analog I/O pins. The I2C bus pins (SDA, SCL) are also readily available. These are conveniently brought out to headers on the side of the board.
ControLeo is easy
ControLeo uses the standard Arduino environment. We've provided a library (https://github.com/engineertype/ControLeo) that should be installed into your Arduino environment using the instructions found here: http://arduino.cc/en/Guide/Libraries. The single ControLeo library gives you access to all of ControLeo's functionality. Installing the library also installs all the sample code we've written for it.
In Arduino, select the board as "Arduino Leonardo". Your sketches can then be sent to ControLeo using its micro-USB port.
ControLeo uses a quality off-the-shelf flame-retardant ABS plastic enclosure with a textured finish. The holes are CNC machined to perfectly fit ControLeo. The result is a high quality, tight fitting case that looks very good. We are thrilled with this enclosure. Only the lid has holes; you'll need to make a hole to route your wires through the case.
ControLeo specifications and features
- ATmega32u4 microcontroller with Arduino Leonardo boot loader - 32Kb Flash memory, 2.5Kb SRAM and 1Kb EEPROM
- LCD display - 2 lines x 16 characters. The backlight is controlled programmatically.
- 4 relay outputs - The maximum current per output is 220mA. There is a LED indicator with the output is on.
- Buzzer - 90db at 10cm, 3.6kHz
- 2 momentary buttons
- ABS plastic case - custom fit, flame-retardant (UL94-5VA)
- MAX31855 thermocouple - capable of reading temperatures from -200°C to 1350°C (optional)
- Real-time clock - using the DS1307 (optional)
- Input voltage: 5V (USB) or 7-15V DC (screw terminal) - When powered using USB, a total of 500mA is available at 5V and 3.3V. The microcontroller and LCD screen consume around 40mA. Mechanical relays typically consume 50mA each, and SSR's around 5mA each. When powered using a 7-15V supply, a total of 1A is available. Only boards that have the MAX31855 thermocouple IC will have 3.3V regulator populated.
We made the basic ControLeo as cheap as possible, but it is capable of so much more when it knows what the time is, and how hot it is.
Having a real-time clock on ControLeo means you can switch relays based on the date or time. You probably don't need this if you plan to make a pottery oven, but if you want to control lawn sprinklers you'll probably need it. The module has an I2C interface, leap year compensation and has an accurate calendar to 2100. The battery (CR 2032) will NOT be included because of FAA and USPS regulations.
This option adds a lot of components to the ControLeo board, including a 3.3V regulator and a MAX31855 K-type thermocouple-to-digital converter. The MAX31855 is capable of measuring from -200°C to 1350°C (-328°F to 2462°F) in steps of 0.25°C. We ship it with a 1m (3.3 ft) long thermocouple capable of measuring from 0°C to 800°C (32°F to 1472°F).
If you think you're handy with a soldering iron you can choose to do some of the work yourself and save a bit of money. The soldering isn't difficult, except for the LCD screen. It is important to ensure that the screen is level so that it fits perfectly in the enclosure. Failure to do this can result in "sticky" buttons.
A note about relays
ControLeo was designed to work with 3 types of relays. Relays are connected using screw terminals, or in the case of a 4-channel relay module using a 6-pin header (5V, GND and 4 outputs):
- 5V mechanical relays with no additional circuitry required
- 4-channel 5V relay modules. These are common on eBay
- Solid-state relays
Shipping to USA addresses will be done using USPS Priority mail with tracking numbers. International supporters can choose one of two shipping options:
- USPS Priority Mail International for $30 (fast and tracking number)
- USPS First Class Package for $12 (slow and no tracking number)
Canadians can subtract $5 from these prices.
We are confident that you'll like ControLeo. If for some reason you don't like ControLeo just send it back to us within 30 days and we'll refund 100% of the money you paid to Kickstarter. We'll happily eat the fees Kickstarter and Amazon charge us for your transaction. Hmmm, no - we won't be happy paying those fees, but we'll be happy that you're happy. That's what is really important to us.
During the Kickstarter campaign we'll be closely monitoring pledges to determine production quantities. We've already built 12 prototype boards so we've been able to identify components with long lead times. This is reflected in our delivery schedule. For example, the ATmega32U4 is often unavailable for months so we have ordered (and taken delivery of) this part to meet all production goals this year. In fact, we have already spent $4,000 on components to meet the production goal.
We have had two prototype runs so far. We have just ordered version 1.2 boards (shown in the schematic above) which should be the final version. This changed the USB connector to through-hole, added support for the RTC and a few other minor changes.
We'll be doing the bulk of the assembly in our garage using components sourced from Digi-Key, Mouser and others. We'll be using robotics students from the local high school to help with assembly, testing, packaging and shipping. We use Kester EM907 lead-free solder paste, and source ROHS components where possible.
If quantities exceed what we think we're capable of assembling ourselves, we'll most likely outsource our assembly to a fab house based in Silicon Valley. It is important to us to keep an eye on quality, and to ensure a predictable shipping schedule.
Life after Kickstarter
We think ControLeo is very useful, and imagine that anyone supporting this project will think so too. We plan to produce a lot more than required, especially if it means reaching economies of scale. We plan to make ControLeo available on eCommerce sites for a MSRP of $89.
The team behind ControLeo
Peter and Gary are neighbors, living in Cupertino, California. Gary is the hardware guru while Peter comes up with crazy ideas, handles board layout and production and writes software. We're both retired after long careers in Silicon Valley but can't stay away from electronics. Peter wrote software for routers for 3Com, smartphones for Palm and tablets for HP. Gary managed a number of integrated circuit design groups at National Semiconductor. He was responsible for the development of multiple digital logic families. He directed the design, application, business development and production of numerous high volume mixed signal integrated circuits during the 1980's and 1990's.
This is our primary hobby, and we love what we do. We hope you support this project because it will give us greater incentive to push forward with some of our other ideas - which we think are really cool!
Risks and challenges
Peter has supported more than 50 Kickstarter projects to date, and has learned a lot from them.
There are a number of risks in this project:
1. Component lead times
We've already built 12 prototype boards so we've been able to identify components with long lead times. We have ordered (and taken delivery of) all of the components we thought might be problematic. In fact, we've already spent $4,000 on components. We don't anticipate any problems in this area for the first batch ending in December. We may run into issues buying components for the March 2014 batch, but we have time to solve any supply issues that arise.
2. Component specification
There may be a need to re-spin the PCB as components become unavailable from one manufacturer and we need to switch to another part. To this end we have based our designs on common parts. Where this is large price/quality variation in a part (for example, the buzzer) we have pre-ordered large quantities to make sure we have the materials needed for production.
The initial assembly will be done in a garage in Cupertino (how cool is that?). That way we can keep a close eye on quality and performance and have a predictable production timeline. We have already built a large number of boards this way, and feel confident about doing this. If the demand for ControLeo is huge, we expect to outsource assembly most likely to a production house based in Silicon Valley.
4. ABS plastic enclosure
We love the feel of this box! We are using an off-the-shelf enclosure with the holes cut out using a CNC machine. The company we use is based in Ohio, USA and they ship millions of enclosures every year. We have already taken delivery of 50 boxes to cover the early rewards and don't expect any issues when ordering the remainder.
- (44 days)