...
- Power Electronics to track max power point to get most power out of array
- Bigger cells
- Make MISO and MOSI pins actually correct
- 1 RTD chip per 8 sensors with a decoder (with a select pin)
Maddie's Notes
- Switching to newer generation cells. Bigger and more efficient → around double current, will need to update board and increase size of capacitors and inductors to match (running sims for this)Power Gen:
Make car go
- Buy cells and do stuff
- Design power electronics for mppt, boost voltage
- Regulations: only commercial silicon cells, max 4 m^2, only 6 types/sizes max
New things:
- Buy better cells, update MPPT to match, improve blackbody A
- Newer cells (Maxeon Gen 5 and 6) have doubled current so MPPT needs to be redesigned with bigger inductors and capacitors (1
- BlackbodyA tracks temp and irradiance in car. MISO and MOSI swapped so gonna fix that, simplify with MUX/decoder for RTD, fix shorted I2C wires to support >1 irradiance sensors
- Matthew is working on /has sims for ideal inductor capacitor size
- Irradiance sensors: something about there being global and local maxima and there are algorithms to find local maxima but the irradiance sensors tell you when to run to check for global maxima because we don't want to get stuck in a local one but global one takes time so we can't do it all the time,
Diya's Notes
Q: blindspots - how they work
...
Fuse on each branch needs to be implemented.
Maddie's Notes
Power systems
- Next gen goal: improve battery pack safety and reliability, accelerate battery manufacturing process, optimize power usage and reduce waste
- Main battery must power majority of systems
- Considering dual charging
- Battery: manufacturing was hard and doesn't work so well, so want better mode of connecting modules and organizing sensors. To many difficulties created in the name of modularity -> maybe reprioritize
- Cell manufacturing: sample instead of test everything single one
- Going to try to design a PCB to help them connect better
- Ignition switch redesigned
- Currently signals go through Controls ex to turn stuff on the signal just goes through Controls
- Q: Does characterizing each cell help much?
- So far curves look very similar and many teams just sample too
- Q: We need to have a fuse on each branch. Do we have a fuse on each branch?
- Working on it
- Going to use the same configuration next year but change connectors and manufacturing
- Need impedances of each module to be the same which is why in part they were trying to characterize every cell but they seemed very similar so they will probably be fine
- Modules are in parallel so impedances of each model doesn't really matter?
Notes on BPS Presentation
Ishan's Notes
...
recovery is for CAN stuff
Maddie's Notes
- Volt, temp, amperes board
- Uses Micrium RTOS, send CAN transmissions
- Next gen: maintain features but want to standardize hardware, drivers, communication protocols
- Desired improvements: active battery balancing, accurate state of charge, battery health, system fault recovery
- New features: isolation between frame and HV line (required by regs??), contactor weld detection on array contactor, switch from IsoSPI to CAN, tachometer feedback from fans (to know when fans are dead), bluetooth debugging
- Q: current battery health? Why just nice to have?
- Currently don't do anything, hard to do because requires measuring impedances, would tell you how damaged the cells are
- Q: how to implement active battery balancing and active state of charge?
- Not using cells to charge each other, more like passive battery balancing
- Characterizing system state through probability stuff, state estimation through IV cures, AC DC
- Q: on fault recovery:
- BPS currently shuts down for everything but doesn't need to.
- Something about contactors
Stuff that may need to be addressed in PDR
...
- Figure out dist. sensor before PDR so Aeroshell can make cutouts depending on size
- Wire harnessing wants a small board that they have to route less wires to in the back of the car (LIN? CAN?)
- Icons for steering wheel? Coordinate with Ergo to figure out
- Ask Akshay what he was saying to Philip and Steven about Regen stuff
Questions from SRR Q&A
- Q: How do we blind spot monitoring?
- Distance sensor on sides
- Q: On blind spot: add something more to notify faster and more imperative?
- Q: Also steering wheel is getting very complicated
- Q: Separate display that all systems can input to that is its own device on CAN instead of going through Controls?
- Q: What is the justification for putting two-wheel drive on Controls' requirements review (sort of is this all in your system's jurisdiction)
- Q: on display options?
- Q: Where are we placing blind spot tracking?
- Sides (would have to make cutout for that)
- Q: How does the new one pedal mode help?
- Most cars implement the new way so it will be more intuitive
- Q: Any plans to change current backup camera?
- No current plans to change that. Considered adding it to the display but the driver needs to see it at all times anyways
- Q: On coasting with one pedal mode
- Q: What does pedal input match to:
- Current, but velocity in one-pedal mode
- Q: Amount of switches?
- GPIO extender (which goes on the SOM)
- Q: Still planning to use dashboard as simboard?
- Maybe not could be annoying
- Q: fan potentiometer -> scroll wheel on steering wheel?
- Perhaps, but maybe don't want it changed too easily