"expected error before @ token"

iPhone programming like a noob - expected error before @ token 10.16.2011 - I've recently been teaching myself to program for the iOS platform in Xcode using iPhone Programming: The Big Nerd Ranch Guide (I have no idea what level of permanence an Amazon.com link has...). Anyway - one problem I encountered while trying to compile a demo program was "expected error before @ token".

Here is an example of an expression that threw me a curveball:

[questions addObject:@"What is 7 + 7?"];

It turns out that not all quotation marks are created equal, and the problem was due to pasted code from a PDF with fancy slanted quotation marks. Deleting the pasted quotation marks and manually typing the quotation marks immediately solves the problem.

Just a heads up if anyone out there is googling for a solution!

TURRET PROJECT 1.10.2011 - Hmmm.... First off I realized the error in my naming convention for these blog posts, from here on out I'll be using this new format (very exciting I know...). I'm going back down to North Carolina for work, so it looks like this project is on hold again. In the mean time, I've installed OpenCV using this tutorial, and will try to get some projects up and running using XCode on my Intel Macbook Pro.

TURRET PROJECT DEC.2 - So I'm at the point of building the fundamental code on my Arduino Uno board, and realized I should specify what my goals are here. This project will comprise two design milestones, as shown below.
Turret Mk I

• Two degrees of freedom
• Manually operated by pushbuttons or joystick
• Airsoft gun and laser site mounted on end effector

The second milestone will include everything from Mk I and the following:
Turret Mk II

• Camera attached to the end effector, and linked to a computer for target recognition
• Computer/software (most likely a custom program that uses the OpenCV computer vision library) to automatically manipulate the turret and "trigger" the airsoft gun, with no operator interaction

There is still quite a lot of work to be done, but Mk I is feasible in a very short time frame depending on how quickly the mechanical assembly of the turret can be completed. I'm probably going to buy an off-the-shelf pan/tilt servo assembly to expedite this, since it'll be simple and cost effective.

TURRET PROJECT DEC.1 - Allright - so its obviously been months since I've touched this blog. When I "started" this project, I was working 11 hour days and flying home every weekend, essentially making me work a 65 hour week. The last thing I wanted to do when I got home to my beach house (yes, I happened to be consulting on the Atlantic at the time) was nerd out with a soldering iron.

Now that I'm back home and have more free time, I purchased an Arduino Uno and plan to use that as my main microcontroller board for the turret. I have never used one, but I have experience with Parallax's BS2, and plenty of programming experience... so I don't expect much trouble coercing the Arduino to do what I want it to.

I'll be updating more frequently, starting with a breakdown of my plan, from here on out.

TURRET PROJECT JUNE.1 - The objective of this project is to create a stationary weapon that is capable of autonomously recognizing "targets". I plan to use a webcam to collect visual information, OpenCV to process the information, my laptop as the brain, servos controlled by a micro controller to position the weapon, and an electric airsoft gun as the weapon. I have had previous experience with OpenCV from a computational perception class, so making software for the turret to rudimentarily recognize what it is "seeing" shouldn't be difficult. Additionally, I have programmed micro controllers to make fairly complex digital circuits, like a digital tachometer and a line-following robot. Other than those bits of experience, this will be quite the ride for me!

Turret Project

I've decided to flex my skills from my mechatronics and computational perception classes in school and design and build an autonomous airsoft wielding autoturret. More details to come.

ROBO-ONE Dance Competition

I had nothing to do with this project - but thought it was worth sharing. I appreciate the fluidity of some of the robot's moves, other competitors had jerky servo movements. The EL wire was a cool addition for a bit of daft punk flare as well.