World of Russ

Scout Publicity

Russell — Wed, 16 Jun 2010 18:38:13 +0000

Scout at the Spring 2010 ITP Show

Here are a list of articles on Scout:

Semageek (French)

Scout | Project Photos

Russell — Mon, 10 May 2010 03:05:34 +0000

Here are photos of Scout, showing the progression of the project and all of iteration of Scout along the way.

Week 13-14 | Final Project

Russell — Fri, 30 Apr 2010 04:24:28 +0000

My final Nature of Code project is creating the effect of 3D audio with only two speakers. The process to create the effect of 3D audio is to invert the left channel. Next, is to reduce the amplitude of the left channel and feed into the right channel. This process is done to the right channel but vice versa. Next is to add a delay to each the left and right channel. The last step is to mix the processed audio back into the original audio track. The effect is a binaural 3D sound field.

Here is a demonstration of the 3D effect – 3D Sample

Original Track – Sing, Sing, Sing

3D Effect - Sing, Sing, Sing

A sound is placed in the horizontal plane by processing the sound with recorded head-related impulse responses.

Wildlife Final Presentation

Russell — Wed, 28 Apr 2010 18:23:26 +0000

http://docs.google.com/present/view?id=dwb68x9_49frgmm4hk

Using XBee’s for Wildlife Tracking

Russell — Sun, 25 Apr 2010 02:34:41 +0000

Using XBee 900′s for Wildlife Tracking

Urban Range Test Setup

We wanted to find out if XBee 900′s could be used as tracking system. Our first test took place at Washington Square Park. We used two XBee Pro 900 RPSMA. Monkey XBee was fitted with a Digi 2 dBi 7 inch omnidirectional antenna. The trackers XBee was also fitted with the same omnidirectional antenna. One person stayed with the trackers XBee at Washington Square Park, while the other person walked north on Fifth Avenue with the monkey XBee. We were able to get a range of .48 kilometers or 1/3 of a mile with the omnidirectional antennas. We then changed the trackers antenna to a 12 dBi Yagi directional antenna. Using the Yagi antenna increased our distance range marginally. We were able to get an additional .09 kilometers or 300 feet from the Yagi. We did use the Yagi antenna to increase range but to locate the direction of the monkey.

The second was at Central Park. We repeated the first test to see if the trees and foliage changed our results compared to the urban environment of Washington Square Park and Fifth Avenue. The distance range was similar to urban test, the real issue is radio interference. We observed packet loss with the XBee’s. This issue is a characteristic of a highly sophisticated networking protocol. Our conclusion was the XBee’s are not a suitable solution for replacing the current analog tracking system.

Scout Update

Russell — Fri, 16 Apr 2010 04:26:15 +0000

For the past 3 weeks I have been working on Scout. I want to build a small helicopter that uses tilt-rotors. I am on the 3rd revision of Scout. I have hit some roads block such as burnt motors and ESC. The helicopter’s frame fought me tooth and nail. I had my moments of disappear thinking I would never get Scout to work, but I kept at it and have had moments of elation that I will persevere. I learned a lot from the whole process. This design is straight from my head and I am ecstatic to see my ideas in a tangible form. I am currently on prototype 4 of Scout. This version of Scout is fully running yet is a Spruce Goose when come to flying. In my first test flight, I could only get Scout to hop in the air. The helicopter is simply too heavy to fly. Before I even ordered a single part I did do my calculation to see if Scout would fly with the motors I chosen. I arrived with a power to weight ratio of 1.31:1. This is too close for comfort in terms of getting Scout off the ground. It does however go like hell on the ground. I will have to reduce the weight of the aircraft in my fifth revision. Stay tuned. Enjoy the video!

Scout’s First Test from Russell de la Torre on Vimeo.

Week 11 | Final Proposal – “Scout”

Russell — Thu, 08 Apr 2010 19:36:05 +0000

Scout

For my final mechanisms project I would like to build a twin tilt-rotor remote controlled helicopter. I am calling it “Scout”. I found that most types of remote control helicopters are very hard to fly for beginners. Current R/C helicopter design come in two style coaxial rotors and single rotor with a tail rotor. The coaxial rotors offer very stable flight but are not agile. The single main rotor design offers great maneuverability but are hard to fly for novice users. I want to create a hovering aircraft that is easy to fly and very nimble. I also want the helicopter able to carry loads such as cameras and small payloads.

I will be building Scout out of LEGO Technic building blocks. I choose to build Scout out of LEGO bricks for several reasons. First, LEGO bricks are a great prototyping platform. I can build and rebuild my ideas very easily. The cost of materials is cut because I can reuse LEGO bricks. If I were to use a material such as aluminum once I cut a piece thats it I cannot go back. Second, LEGO bricks are accessible to everyone. I want people able to build Scout on there own with minimal amount of tools. Third, going back to my first point, LEGO bricks offer modularity. If I decide later that I want to add another battery bay or a camera arm to the helicopter, I can easily snap those parts into the main design.

I will be using two electric ducted fans (EDF) for the propulsion. The frame will be made out of LEGO Technic. I am using several kits to build the helicopter. I need to use several kits because one kit doesn’t include all the parts I need to build this helicopter.

Here are the LEGO Technic kits that I will be using:

LEGO 8297 Off Roader
Qty. 2 – LEGO 8265 Front Loader
LEGO 8258 Crane Truck

I also acquired various parts such as gears and shocks off of eBay. The helicopter is essentially two helicopters in one, hence I will need two of everything. Each EDF will need an electronic speed controller (ESC), and battery. I will also need a decent radio system. I choose the Futaba 7C 7-Channel 2.4GHz Heli with 4 S3152 servos. I choose the 7C because I need to do servo mixing. Servo mixing is when two or more servo move together with only one joystick movement. Cheaper radio cannot do this function. The motors I will be using are 3600kv Outrunner Brushless Motors. I will be using two 45A Brushless ESC. The batteries to power Scout are lithium-ion polymer (LiPo) batteries. I chose two 11.1 volt 2800mAh 30C batteries.

Scout isn’t cheap but compared to current helicopter in it’s class it is a bargain. I sourcing the EDF and batteries directly from Hong Kong, China. I saving over $300 ordering directly from China. All the electronics parts are made in China. The US stores order their parts from China. I am cutting out the middle man by ordering directly from China. The downsides of ordering from China instead of order from the US is the shipping duration is weeks instead of days. The other issue is the build quality of parts can be can be hit or miss. You may order two batteries, one battery may operate perfectly while the other is DOA. Chinese seller will replace your defective battery but you will have to send them the defective battery and they will not reimburse you for the return shipping cost. Even with the risk of a DOA parts, it is still cheaper to order directly from China. Price list of Scout are below.

Price list:

LEGO 8297 Off Roader….$130
LEGO 8265 Front Loader….$80 x2
LEGO 8258 Crane Truck….$250
EDF with Motor and ESC….$48 x2
Futaba 7C heli with servos Radio System….$350
11.1v 2800mAh 30C LiPo Battery….$25 x2

Grand Total $1036

Schedule:

March 15 – April 10….Order supplies

March 20 - April 16….Begin Construction

April 17 – 20………….Begin testing and setting up the radio

April 21 – 27………….Test flight and revise

April 29……………….Present

Here is my concept design for Scout. I used Omnigraffle to create the concept design. I measured the parts and input them into Omnigraffle to get an accurate scale of my design.

Scout Diagram

First Prototype of Scout

Scout Proposal PDF

The PDF proposal also includes a part list with the weights of each part. I also calculated the total power to weight ratio of Scout.

Telemetry Receiver vs. Uniden BC346XT-Round 2

Russell — Tue, 06 Apr 2010 23:19:40 +0000

Taking the advice from Eric Rosenthal I retested the Uniden radio receiver against Tony’s telemetry radio receiver. I setup the Uniden by turning off all the auto features and manually controlling the frequency stepping. I used the good collar which has a frequency of 148.500 MHz. The setting that Eric Rosenthal recommended were set in the first round of testing and remained for this test. The only change was I set the radio to manual mode instead of automatic. The second test mimic the first. I set the collar at a fixed position while I walked away from the collar with the telemetry receiver and the Uniden receiver in my hand. One curious fact that I found in conducting the test was stepping the frequency higher and lower from the base of 148.500 MHz proved to increase the reception of the signal as I increased distance from the collar. I stepped the frequency .1 KHz on the telemetry receiver and I stepped the frequency 10 KHz on the Undien (this is the minimal step increment for the Undien). When I heard the signal dying off I would increment up and down the frequency to improve reception. This was affective for the telemetry receiver but doing the same to the Uniden did not result in a better reception. Both receiver received a clear signal for about 300 feet. After 300 feet the Uniden receiver began to lose the signal as I walked further away. In short the first test that Zeven and I did were accurate. The settings that Eric suggested were indeed what we had configured for the first test.

No change the Uniden scanners won’t work.

Week 12 – Final Project Proposal

Russell — Tue, 06 Apr 2010 03:04:02 +0000

For my final Nature of Code project I want to continue building upon my Audio Analyzer. I would like to 3D audio using only two speakers. The process to create the effect of 3D audio is to invert the left channel. Next, is to reduce the amplitude of the left channel and feed into the right channel. This process is done to the right channel but vice versa. The effect is a binaural 3D sound field. Currently, I have never tried this process and will see if this process works.

Audio Analyzer Mac App

Source Code