Mechanical Dust

Building Physical Curves

An introduction to the curves used to build physical things, especially to B-Spline curves and their properties.

Spivak's Calculus on Manifolds

One of my projects is to thoroughly digest Spivak's Calculus on Manifolds by writing up my own set of notes, complete with diagrams and solutions to every problem.

Perpetual Calendar

This blog documents my progress designing and building a perpetual calendar watch.


This is a new way to graph data, especially good for small numbers of points, or sets with sparse regions.

Gear Geometry

There is a clean and simple way to extend Euler's beautiful involute construction to gears with skewed axes.

Talk on Machine Vision

These are notes from a guest lecture I gave in 2012 to a linear algebra course at UT Austin.

Notes on Stereographic Projection

Just checking that circles actually map to circles.

Notes on Flatness

Some beautiful math comes from computing the flatness (aka width) of a collection of points.

Rectangles On A Grid

How many ways are there to place rectangles against the same background grid? This question comes up during page layout (web pages, magazine pages, etc).

Pan Long Village

These people are photographing me, and I am photographing them.

Making Things

Various trinkets I've made.

Notes On Probability

Notes on some basic aspects of probability.

Reading All My Books

My enthusiasm for purchasing books outpaced my reading speed many years ago. The idea here is to create some kind of web tool for keeping track of everything.

Motorcycle Localization

Dead reckoning on a motorcycle is tricky because the motorcycle leans during a turn. A simple model of these dynamics allows for position updates using gyroscope and odometry data.

Curve Encirclement

A novel way to understand and quantify the shapes of curves, with application to physical curves, such as protein molecules.

Dorian Clair Antique Clock Repair

Dorian is a master mechanic, and the most talented and pragmatic mechanism debugger I have ever met. I apprenticed in Dorian's shop as a teenager.

The Algebraic Ricatti Equation

The Algebraic Ricatti Equation is a quadratic equation in matrices.

Euler's Disk

How does a coin spin on a table? Does it slip, or does it roll without slipping?

My UC Berkeley Homepage

Old notes, papers, teaching evaluations etc are all accessible here.

Maciej Zworski

Maciej was my MS advisor in mathematics.

Oliver O'Reilly

Oliver was my PhD advisor in mechanical engineering.

Coyote Yipps

My mom photographs and documents urban coyote behavior.

FYI France

My dad writes about French libraries and other topics.

Copyright 2023 by Patrick Kessler. All rights reserved.