6.1: 9/27-10/1
In preparation for the weekly meeting with the professor, the team worked on refining the remaining two proposal ideas.
The Sonar Boat was the most recent addition and required more attention than the ANC device.
Research showed that a triple-shot transducer provides superior resolution and field of view.
The pictured device called “Triple Shot, by Lowance” allows for down and side scanning as well as a high-frequency CHIRP.
6.2: 10/1-10/4
The ANC for Rigid Barriers was approved by the professor.
The remainder of the week was spent elaborating on the details of the proposal.
A table was created in which all block diagram sections were described in greater detail. Information regarding their function, materials required, and nature of development were included.
Many updates were made to website to make it more user friendly and aesthetically pleasing.
John
John created a user profile on AD’s EngineerZone forum.
After a few days of scouring the available discussions and threads, John made the post shown in order to try and obtain some expert advice.
So far he has received no replies.
The conclusion of john's research showed that ADAU1452/66 are some of the better options for ANC development
These two devices are functionally identical. The key difference is the 1452 has less onboard memory
The included video shows an ADAU1452 being used to perform an ANC algorithm for a coffee maker
ANC is best suited for periodic continuous noise signals. Thus our project will aim to address noise of this type
A preliminary layout of the touchscreen user interface was developed and discussed with Hunter, since he will be designing the UI for the touchscreen since he has more experience using Arduinos and Raspberry Pi’s.
The objective will be to display the (2D) frequency spectrum amplitude response of both the incoming noise and noise/anti-noise summation.
Targeted frequency, Noise Loudness, Battery life, and Device Temperature will also be displayed
While the ADAU1452/66 is perhaps the best DSP option, the official Eval-Board has severe latency limitations.
The ad1938 audio codec is included on the board for ADC/DAC but is hardwired to run at 48kHz max.
The throughput group delay of the ad1938 @48kHz is 1ms which is to high for effective anc.
A possible solution is to instead purchase a 3rd party ADAU1452/66 evaluation board. These boards do not include the audio codec and can therefore be integrated with a device with superior latency performance. This would also allow the board to operate at 192kHz sample rate, further decreasing latency.
Forum research has shown that users can successfully integrate these boards with SigmaStudio. Both team mates purchased the DSP board and USBi programmer for SigmaStudio to start practicing with as soon as possible with current shipping times being longer than normal.
The Cirrus CS4271-CZZ is a stereo audio codec with a 192kHz latency of 50us
The devices will communicate via serial audio interface I2S
Hunter
(Week 6) Project and Updates:
Maxbotix sell high quality transducers that Hunter has been researching to use for the sonar project. Currently, the MB7060 XL-MaxSonar WR1 transducer is being considered since they are known to be accurate and it has a narrow beam pattern (which is usually best for down scan and top/lateral scanning). The sensors range capability is from 20cm to just over 25ft, this being within our depth range, and it can also be made waterproof up to 3 meters, which works since we only needed about 1 meter to be safe.
The decision is yet to be made as to wether or not we should design our own sonar device, or if it would be better to buy a brand name sonar and add a different form of complexity to the design, if we decide not to design the sonar device itself. There is a large amount of code that is required to use a transducer for underwater mapping and working in sync with the GPS, and to also include object detection and marking its location.
The amount of programming for this project is starting to raise some concern since our background is primarily focused on electronics. This is our final week to decide if we should use a brand name sonar device and/or make any other revisions to the design.. Source
Collaboration for each design has continued on discord or by phone through the week discussing any new information, progress, or questions that we might have. Here are a few resources that Hunter found in reference to calculating depth, transducer placements, and types of scanning methods to use or rule out for this.
Extensive research was required for studying sonar mapping and object detection. However tempting the challenge may be, the more information that is gained from studying, the more apparent it becomes how complex the programming is for attempting to design a sonar mapping and object detection system from scratch without using a brand name sonar to help lighten the load so the idea itself is achievable within the given time frame of 8 months. The final decision was made to look into brand name sonar devices rather than making one on our own.
In attempt to confirm which brand name transducer is the most efficient for our sonar project, and to get a professionals thoughts on the type of scanning methods we were thinking of using, Hunter went to Bass Pro Shop this week, called West Marine, and Garmin to get their professional feedback.
Eric, at Bass Pro Shop, seemed very interested in the idea and suggested one of the transducers that we were already considering called the “Triple Shot”, by Lowrance. Lowrance, was previously considered since their products work with other 3rd party devices, unlike Garmin's marine products which only work with their own marine line.
Chase, from West Marine, and Eric from Bass Pro both recommended OpenCPN source code for developing this type of shallow water mapping. Garmin did not give out much information, other than explaining that in order to map bodies of water we would have to purchase all Garmin products, including the GPS, and can only use it with their own software. If the project is accepted the Triple Shot sonar device by Lowrance will be used.
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