From bf9590e91d78c7f6a1256847e54609b100cd2f79 Mon Sep 17 00:00:00 2001
From: toaster-person <64749149+toaster-person@users.noreply.github.com>
Date: Sat, 20 Dec 2025 20:14:43 -0800
Subject: [PATCH 1/4] dfc outline + backlash
---
docs/design-handbook/design-writeups/DFC.md | 35 ++++++++++++++++++++-
1 file changed, 34 insertions(+), 1 deletion(-)
diff --git a/docs/design-handbook/design-writeups/DFC.md b/docs/design-handbook/design-writeups/DFC.md
index 0ea8ae0f9..5dc72ec2e 100644
--- a/docs/design-handbook/design-writeups/DFC.md
+++ b/docs/design-handbook/design-writeups/DFC.md
@@ -2,7 +2,39 @@
A guide on designing mechanisms and power transmissions for controllability. Make your programmer's life easier.
-**WIP**
+# Backlash
+
+In mechanical systems where precision is needed, it is imperative to reduce backlash. **Backlash** is defined as the distance/angle that a component can move before it engages with another component. For example, in gears there is a tiny amount of space between the interlocking teeth of two gears, which allows one gear to move slightly before moving the next gear. This slop in a system caused by gaps in the parts. For FRC, this could be gaps between gears or between the motion component and the axle. Too much backlash in a system, especially for cases that require high precision (like pivots), will make the system unstable and inaccurate. Thankfully, there are many ways to reduce backlash.
+
+## Power Transmission Methods
+
+When choosing how to transmit rotational power, understanding which methods cause the most backlash can guide decision making. Of the three main types of power transmission in FRC (chain, belts, gears), each have their own pros and cons.
+
+**Chain:** Chain works well in high-torque scenarios, commonly in pivots. Chain transmissions are capable of having large backlash that reduces a mechanicam's accuracy significantly. However, if designed right, chain transmissions can have minimal backlash. This means having as much wrap as possible around sprockets and including chain tensioning. More information on chain tensioning can be seen in the [tensioning section](google.com) under the design writeups.
+
+**Belts:** Belts work well in low-torque, high speed scenarios. They are used in many applications such as rollers, elevators, and sometimes small pivots. They are notable for having nearly zero backlash due to the way the belt engages with the pulleys. However, they are also weaker than chain, so they are not suitable for most pivots where minimal backlash is useful. They can still be very useful in elevators, where many designs utilize belt for linear extensions.
+
+**Gears:** Gears are the most versatile type of power transmission. They are useful in virtually every application, whether it's switching direction on rollers or pivoting an arm.
+
+## Using Less Stages on a Gearbox
+
+The easiest way to reduce backlash in a gearbox is to use less stages.
+
+## Shim Tape/Green Locktite
+
+
+
+## Tensioning
+
+
+
+# Hardstops
+
+
+
+# Encoders and Sensors
+
+
+
\ No newline at end of file
From ef8458b8222369270b164a8f0719fcbf2c1ad01d Mon Sep 17 00:00:00 2001
From: toaster-person <64749149+toaster-person@users.noreply.github.com>
Date: Sat, 27 Dec 2025 12:16:20 -0800
Subject: [PATCH 2/4] backlash stuff
---
docs/design-handbook/design-writeups/DFC.md | 60 +++++++++++++++++-
.../design-writeups/images/backlashimage.webp | Bin 0 -> 189678 bytes
.../images/shimtapeprocess.webp | Bin 0 -> 632156 bytes
.../design-writeups/images/shimtapestep1.webp | Bin 0 -> 573134 bytes
.../design-writeups/images/shimtapestep2.webp | Bin 0 -> 632156 bytes
.../design-writeups/images/shimtapestep3.webp | Bin 0 -> 584540 bytes
6 files changed, 58 insertions(+), 2 deletions(-)
create mode 100644 docs/design-handbook/design-writeups/images/backlashimage.webp
create mode 100644 docs/design-handbook/design-writeups/images/shimtapeprocess.webp
create mode 100644 docs/design-handbook/design-writeups/images/shimtapestep1.webp
create mode 100644 docs/design-handbook/design-writeups/images/shimtapestep2.webp
create mode 100644 docs/design-handbook/design-writeups/images/shimtapestep3.webp
diff --git a/docs/design-handbook/design-writeups/DFC.md b/docs/design-handbook/design-writeups/DFC.md
index 5dc72ec2e..14905fe25 100644
--- a/docs/design-handbook/design-writeups/DFC.md
+++ b/docs/design-handbook/design-writeups/DFC.md
@@ -6,6 +6,11 @@ A guide on designing mechanisms and power transmissions for controllability. Mak
In mechanical systems where precision is needed, it is imperative to reduce backlash. **Backlash** is defined as the distance/angle that a component can move before it engages with another component. For example, in gears there is a tiny amount of space between the interlocking teeth of two gears, which allows one gear to move slightly before moving the next gear. This slop in a system caused by gaps in the parts. For FRC, this could be gaps between gears or between the motion component and the axle. Too much backlash in a system, especially for cases that require high precision (like pivots), will make the system unstable and inaccurate. Thankfully, there are many ways to reduce backlash.
+
+
+
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