8:00am - 11:00am at ?Andrew's "cabin"
Agenda:
- Prioritization and schedule of our critical path stuff: APS, GPS, Magnetometer, etc.
- Prototype APS (Avionics Power Systems) battery selection, architecture and design handoff to Ted and Ivan.
- GPS stuff.
Notes:
- TR: Split the battery pack? RF Section and other? Use a polyfuse on the RF section?
- AG: Let's try shorting across a polyfuse to see what happens to the rest of the avionics
What we decided to do: keep the APS just as it is now (a glorified power switch with some power monitoring) and have Ted and Ivan develop an independent battery charging circuit with a charging IC.
We decided on a 4 cell pack: however, this means that we need a power switch on the WiFi and on the ATV power amp. Probably just a comparator and an IPS with a NAND gate that doesn't let the PIC turn on the amplifiers if the bus voltage is > 15V (or whatever their V limits are). See data sheets, but: ATV power amp has 16V max input, WiFi power amp has a 15V? limit).
The IC that charges the battery packs: one per pack:
Requirements:
- Charge the freakin' battery when the PIC says there's shore power.
Nice things:
- Battery state of charge
- Battery current and voltage
- Digital interface to the PIC, like SPI or I2c
To Do:
| TR | 1. Get Andrew the graphs for the Kodak batteries if possible. |
Timeline:
Ok schedule:
| 2004/06/01 | Research |
| 2004/06/15 | Schematic |
| 2004/07/01 | PCB Design |
| 2004/07/15 | PCB's soldered up (hardware done) |
| 2004/08/01 | Firmware |
| 2004/09/01 | Freeze |
| 2004/09/20 | Launch |
Reduce Andrew's bloodpressure's timeline:
| 2004/06/01 | Research |
| 2004/06/07 | Schematic |
| 2004/06/21 | PCB Design |
| 2004/07/07 | PCB's soldered up (hardware done) |
| 2004/07/14 | Firmware |
| 2004/09/01 | Freeze |
| 2004/09/20 | Launch |