Phase III Design Review

MSD IIP14347

New Parts Purchased

•User Device enclosure with correct sizing, from McMaster-Carr

•New Battery pack with correct voltage spec for eval boards

•TTL-level USB-to-serial cables•GPS Antenna

Parts Arrived

•User device enclosure•LiPo batteries (3.7V) and charger

Barbed Hook Design•Shape taken from typical

hook designs•Exact dimensioning

depends on application▫Refinement with testing

•Waterjet sheet metal stock and sharpen as secondary operation

•Prototype will be epoxied to the enclosure

Solid/Small Enclosure – Tough Plastic

Solid/Small Enclosure – Weak Plastic

Test Enclosure Design•Two Solid Pieces•Stick together w/ tape

▫Final design would include snap fit•Tethered on the inner flats•Rests on O-Ring placed on custom

ferrule

Enclosure Test Plan Summary•Bale of hay @ ~20 yards

▫Secure a marked piece of deer hide over hay▫Possibly put “flesh-like” object behind hide

•Test shot w/o attachment to see effects of broad head on hide

•Shot w/ attachment to verify detachment and hooking

•Follow-up testing if it doesn’t break•https://www.youtube.com/watch?v=cCrKeE

yJmFo

Meeting with Poseidon Systems• Transceivers put in direct communication

with the computer using two TTL-level usb-to-serial adapters (one for each).

• Used RealTerm to send messages to them, with the CMD line grounded (all incoming data was processed for configuration rather than transmitted)

• The program was used to read each modules address (1: 00|14|C7|48, 2: 00|14|C8|B7)

• In each transceiver, the GUID registers (#’s 68, 69, 6A, and 6B) were written to represent the other’s module address.

Meeting with Poseidon Systems•Put transceivers in “all broadcast mode” so

any signal between them would be picked up •This was done by writing FF to the GUID

registers rather than the module address.▫Interference should not be an issue

•Once both were put in broadcast mode, RealTerm was able to be used to send messages written as well as display messages read.

•They recommended looking into ‘Python NMEA decoders’ on google for some help with the LCD display code.

LCD Screen Coding

•Poseidon Systems recommended looking into ‘Python NMEA decoders’ for assistance with LCD screen display code

•http://www.scaryclam.co.uk/pynmea/docs/StartingOut.html

Next Steps

•Resolve remaining GPS issues•Integrate new GPS antenna•Work on LCD screen code•Barbed hook and arrow attachments

made