Efficiency Miser Mode

Moved from another thread so that I don't take it too much off-topic.

jerry33 said:

This idea has come up many times in the Prius groups. Do you know of any existing cruise control that has actually done this? It's a great idea, but I don't think it's ever been implemented :-(

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An elementary algorithm would be fairly simple to write. In fact, if the SDK allows us to create things like "custom valet mode" I'll probably write it.

Efficiency Miser Mode, V1
Settings

1. Maximum speed deviation. Default is 10mph.
2. Maximum power consumption. Default value is 40 kW.
3. Maximum regeneration rate. Default value varies depending on Regeneration Strength setting: 0kW for Low, 10kW for Standard.

Usage

1. User evaluates and adjusts settings listed above, and enables EMM.
2. User begins driving, enables cruise control, and sets target speed at 60mph.
3. Cruise control behaves as normal but with the following modifications (numbers shown use the default values above assuming Regeneration Strength setting is on Standard):
   • Speed target is within the [50,70] mph range rather than [59,61] mph range.
   • Power consumption remains at or below 40 kW while the car is above 50mph.
   • Regeneration rate remains at or below 10 kW while the car is below 70mph.

Known flaws with V1:

1. The speed target is difficult to maintain in hilly terrain when the vehicle is on the edge of the speed target range. To address this, future versions should apply a smarter algorithm to adjust the second and third bullets of Usage,3 so that the speed target range is strictly maintained.
2. In emergency situations, the user needs to be able to disable the acceleration limiting temporarily. Perhaps simply disabling the limiting when CC is off is an option, but some users will want to use EMM with non-CC driving as well. So maybe use something like tapping both pedals at once is a good clue to turn off the limiters.

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My closest approximation (so far) to this algorithm has been to set the Cruise Control to 51mph and manually apply throttle to reach up to 70 mph while maintaining consumption at or below 40 kW. When approaching 65mph, I start tapering off so that I don't hit the regen cap when going downhill -- which would require applying brakes or going above the 70mph limit of the speed target range.

Features needed from SDK to implement "Efficiency Miser Mode, V1":

1. Read/write app settings in the form of 4 integers in the ranges: [0-130], [0-320], [0-60], and [0-60].
2. Read/write app setting in the form of a boolean.
3. Set the cruise control speed target.
4. Set Power Consumption limit.
5. Set Regeneration Rate limit.
6. Sample the current vehicle speed.