Is it safe to put your laptop in a bike basket?

I love riding my bike to work, but is it safe to put my laptop in the bike basket while I ride? This question was nagging me and while online forums promise nothing would happen, but I simply couldn’t bring myself to take the risk. After spending my first year of graduate school riding everywhere with a backpack, I decided enough was enough, and set up an experiment to know for sure how much impact a laptop sitting in a bike basket sustains during a typical commute.

After starting SensorLog, I embedded my phone next to my laptop inside it’s inside a carry case, which was itself inside a backpack.

The experiment consisted of three trials; two morning commute bike rides, as well as an evening return trip. Each measured the gravitational force exerted on a measuring instrument (my phone) which was situated next to my laptop inside my backpack, which sat in my bike basket throughout the trip.

I used SensorLog to record X, Y, and Z-axis measurements at 30 Hz, which came out to about 15 samples taken per second over the 7.6 mile bike ride. I averaged the summed squares of the three recordings to calculate a total gravitational force, and plotted these readings over the length of the bike ride.

Accelerometer recording of the morning commute — Oakland to Berkeley. Notice the number of valleys (traffic stops) where the recording falls flat.

Accelerometer recording of the evening commute — Berkeley to Oakland. A slightly downhill, evening ride means fewer logged samples and surprisingly fewer red lights at traffic stops.

Each gravitational reading had an associated longitudinal and latitudinal value, which allowed me to look up where on my ride certain impact events occurred.

Tracing high-impact events to specific roadway features: the drainage grate on campus (red), school-zone speed bump (yellow), pothole filled stretch (green), and curb-hopping (purple).

While the average gravitational force registered around 1.5–2 times Earth’s gravity, there were routine spikes of 5 and 6, topping out at the occasional 7 and 8.

Looking a reference table for context, these numbers are alarming. My favorite Gravitron amusement park ride creates a 2.5–3 g environment for riders, roller coasters boast 3.5–6.3, and the Apollo 16 crew apparently were subjected to 7.19 g during reentry.

So…my laptop was subject to more force on my ride than Apollo 16 on reentry?https://en.wikipedia.org/wiki/G-force

However, there is a difference between point force and sustained force. While a pilot on the Apollo 16 might experience a force of 7.19 g upon reentry, it is the duration of that force acting on the pilot’s body that causes damage. In shorter durations, significantly higher g-forces are bearable. In 1954, Colonel John Stapp experienced 46.2 g for several seconds, and in micro durations of a fraction of a second, accelerations of over 100 g are bearable without significant damage.

A study conducted in 2004 found that many commercially available HDD could sustain over 50 g of point force during operation, with over 350 g, if powered down. SSD drives have no mechanical parts and can sustain ever higher point forces. Intel’s 530 Series of SSD are rated at 1500 g at 0.5 msec.

While your laptop will sustain relatively high degrees of acceleration during your ride to/from work, the severity and duration of the impact is simply not enough to cause any damage.