Circadian half-cycler

The circadian half-cycler is an artificial body part that removes a pawns need to sleep at the cost of a permanent 15% Consciousness penalty.

Acquisition

Circadian half-cyclers can be crafted at a fabrication bench once the circadian influence research project has been completed. Note that this research requires a techprint. Each requires 15 Plasteel, 4 Advanced components, 26,000 ticks (7.22 mins) of work modified by the general labor speed of the crafter, and a crafting skill of 8.

Summary

A circadian half-cycler is installed in the brain and removes the Sleep need entirely. Consciousness is reduced by 15%, which itself reduces work-related stats like Moving and Manipulation, as well as Eating and Talking.

When a pawn with this implant is shocked with EMP, they will receive brain shock, knocking them unconscious temporarily.

Installation

Installing the part requires 2,500 ticks (41.67 secs) of work, 2x medicine of herbal quality or better, and a Medical skill of 5.

Removing the part requires 2,500 ticks (41.67 secs) of work, 1x medicine of herbal quality or better, and a Medical skill of 5.

If the operation fails, the part will be destroyed.

Analysis

Assuming a colonist sleeps for 8 hours, this implant allows them to work an additional 1/3rd of the day, and saves space on a bedroom. Even with the consciousness loss, this makes pawns have more work time, and thus better for many tasks. This assumes you don't have many sleep reducers; see #Comparison to reducing sleep for details on that.

An unfortunate side effect of the half-cycler is mood. No sleep will prevent Lovin' entirely, remove the moodlet from an impressive bedroom, and deprive a pawn of a bed's Comfort level. An armchair can provide comfort for crafter-type pawns, but all these mood-increasers are quite significant. Non-ascetic nobles still desire a bedroom that meets their needs. Also, remember that darkness will reduce work speed, even with a half-cycler, so you'll want to install lights around your base.

Work

The Consciousness loss has a different effect on different work types.
Good:

Research, Hauling, Cleaning: All these tasks are done slower, but have no quality, so the extra time makes up.
Cooking: Like above; food poisoning chance is not increased.
Construction, Crafting, Art: will produce the same-quality items, so the extra time is a net positive. Note that low-skill construction is more likely to fail.

Mixed:

Plants: Allows more plants to be grown/harvested, but lowers yield per plant. Bad when plant space is limited, good if not.
Mining: Good for mining regular rock or deep drilling, bad for mining ores.

Bad:

Social, Animals: The half-cycler is of little help: trade is limited, prisoners and animals sleep. Lowered Consciousness means more failed attempts and higher prices.
Medical: Tends slower, with less quality, and have less successful surgeries. Tend speed is time-sensitive; speed is important, but you don't need to tend all the time.
Combat: Worse accuracy, will get injured more, and more likely to die from Consciousness loss. Being tired does not penalize combat, so the half-cycler is a pure negative.
- EMP also becomes harder to use due to Brain Shock. You may want to use EMP anyway, and if it hits the half-cycler pawn, they'll be stuck downed.

Of course, pawns can be good at multiple work tasks. A pawn that mostly does Crafting can also be your main Social pawn, for instance. Each case should be weighed individually.

Synergy with Genes

Since the half-cycler removes the need for sleep, making any effect on Sleep Fall Rate irrelevant, it synergizes well with the Sleepy and Very Sleepy genes. Both become essentially free negative genes, providing +2 and +4 metabolic efficiency respectively. This is perhaps not enough to make the whole implant worth it alone, but on any pawn who already has a half-cycler, this is a large, completely free, secondary benefit.

Comparisons

Comparison to reducing sleep

For a full list of sleep required in various circumstances, see Rest#Comparison tables.

Other than quick sleeper, the following can decrease the time needed to sleep:

High quality beds, further improved with royal beds
Improvements to digestion and blood pumping (like bionic stomachs, bionic hearts, and luciferium)
Drugs, like psychite tea and wake-up.
Sleep accelerators.
The low sleep gene.

And, of course, the circadian assistant.

The following combinations warrant comparison:

Amazing Beds + Assistant: In total, a masterwork bed + assistant reduce sleep to 5.04 hours - that's 21% of the day. A legendary royal bed + assistant reduces sleep to 3.96 hours (16.4% of the day). If you can easily create Masterwork/Legendary beds, such as with a Production Specialist, then the half-cycler can end up a negative to work compared to a circadian assistant.

Excellent Beds + Sleep Accelerator: An excellent bed + sleep accelerator reduces sleep to 5.1 hours (21.2% of the day). A legendary royal bed + accelerator reduces sleep to 3.75 hours (15.6% of the day). Note that the accelerator does cost a fair bit of hunger and power, and is only available if you have a pawn with a Transhumanist ideoligion.

Just Low Sleep: On a normal bed, low sleep alone reduces sleep to 3.43 hours (14.26% of the day). As the half-cycler reduces practically all work by -15%, this gene is a flat out improvement. The gene comes at the cost of -4 Metabolic Efficiency, which must either be compensated with bad genes, or increase hunger by up to x200%. Sanguophages already come with Low Sleep - installing a half-cycler is a net negative to them.

In all 3 cases, the pawn can still receive a bed's comfort, Lovin', and the Impressive Bedroom moodlets. These scenarios can be further improved with any of the other methods listed above. However, they'll have to walk to and from the bedroom/barracks, which is a minor time loss.

Comparison to Never Sleep

The never sleep gene will completely prevent sleep with no Consciousness loss. However, with a metabolic efficiency of -6, it requires negative genes or archite metabolism to even be used at all. It takes a large amount of negatives to negate the penalty, or 2 archite capsules for the aforementioned metabolism gene.

Never sleep is not found in any of the default xenohumans, so a genepack must be found/bought. You must also obtain a genepack to compensate for metabolism. Alternatively, you can start with a xenotype with the gene - this still comes at the genetic cost.

Artificial body parts

Arm/Hand: Archotech arm • Bionic arm • Power claw • Prosthetic arm • Wooden hand • Drill arm • Elbow blade • Field hand • Hand talon • Venom talon • Flesh tentacle • Flesh whip
Head: Archotech eye • Bionic eye • Bionic ear • Bionic jaw • Bionic tongue • Cochlear implant • Denture • Aesthetic nose
Head implants: Joywire • Painstopper • Circadian assistant • Circadian half-cycler • Gastro-analyzer • Learning assistant • Mindscrew • Neurocalculator • Psychic harmonizer • Psychic reader • Psychic sensitizer • Venom fangs • Control sublink (Standard, High) • Mechlink • Mech gestation processor • Remote repairer • Remote shielder • Repair probe
Spine: Bionic spine • Revenant vertebrae
Stomach: Bionic stomach • Nuclear stomach • Reprocessor stomach • Sterilizing stomach • Fleshmass stomach
Heart: Bionic heart • Prosthetic heart • Heart • Adrenal heart • Corrosive heart • Metalblood heart
Lung: Lung • Detoxifier lung • Fleshmass lung
Kidney: Kidney • Detoxifier kidney
Organs: Liver
Visceral implants: Death acidifier • Aesthetic shaper • Coagulator • Healing enhancer • Armorskin gland • Stoneskin gland • Toughskin gland • Immunoenhancer • Love enhancer • Ghoul plating • Ghoul barbs
Leg/Foot: Archotech leg • Bionic leg • Prosthetic leg • Peg leg • Wooden foot • Knee spike
Related: Psylink neuroformer • Xenogerm
Deprecated: Scyther blade • Psychic silencer