Fix formatting for documentation of IMU Noise Model (#121)

Summary: Pull Request resolved: #121

Test Plan:
Sandcastle doc build

Before:
 {F1784676050}

After:
 {F1784677350}

Reviewed By: PiotrBrzyski

Differential Revision: D60530853

Pulled By: SeaOtocinclus

fbshipit-source-id: 10c9cbf5b8ce2253f887a92bbcbe26741173abd2

Author: sarlinpe

website/docs/tech_insights/imu_noise_model.mdx

@@ -21,7 +21,7 @@ Where:
 - $x^{\text{sampled}}_k$ is the sampled value seen as a random variable.
 - $n^{\text{turn-on bias}}_{k0}$ is a random variable draw from a Gaussian when the device is turned-on (denoted here as step $k_0$).
 - $n^{\text{white noise}}_{k}$ is the time-independent noise components and draw from a 0-centered Gaussian at each step $k$.
-   - The covariance of the Gaussian is usually characterized by the continuous noise $\sigma_c$ strength, which needs to be multiplied by the bandwidth (BW)h in Hz to get the distribution of the sample noise: $\sigma^2_c . BW$.
+   - The covariance of the Gaussian is usually characterized by the continuous noise $\sigma_c$ strength, which needs to be multiplied by the bandwidth (BW)h in Hz to get the distribution of the sample noise: $\sigma^2_c \cdot BW$.
    - $\sigma_c$ is sometimes called *Angle Random walk in $rad/s/\sqrt{Hz}$ or $rad/\sqrt{s}$* for the gyrometer and the *Velocity Random Walk in $m/s^2/\sqrt{Hz}$ or $m/s/\sqrt(s)$* for the accelerometer.
 - $n^{\text{bias random walk}}_k$ is drawn from a random walk process.
 
@@ -31,8 +31,8 @@ The parameters describing those noises can be derived from an Allan Variance plo
 
 ||accel-left | accel-right| gyro-left | gyro-right|
 |--|--|--|--|--|
-|white noise ($\sigma_c$)|$0.9\times 10^-4\ \text{gees}/\sqrt{Hz}$ |$0.8\times 10^-4\ \text{gees}/\sqrt{Hz}$|$5\times 10^-3\ \text{dps}/\sqrt{Hz}$|$1\times10^-2\  \text{dps}/\sqrt{Hz}$|
-|bias instability |$2.8\times 10^-5\ \text{gees}$|$3.5\times 10^-5\ \text{gees}$|$1\times 10^-3\ \text{dps}$|$1.3\times10^-3\ \text{dps}$|
+|white noise ($\sigma_c$)|$0.9\times 10^{-4}\ \text{gees}/\sqrt{Hz}$ |$0.8\times 10^{-4}\ \text{gees}/\sqrt{Hz}$|$5\times 10^{-3}\ \text{dps}/\sqrt{Hz}$|$1\times10^{-2}\  \text{dps}/\sqrt{Hz}$|
+|bias instability |$2.8\times 10^{-5}\ \text{gees}$|$3.5\times 10^{-5}\ \text{gees}$|$1\times 10^{-3}\ \text{dps}$|$1.3\times10^{-3}\ \text{dps}$|
 
 
 The figure below shows the Allan Variance plot supporting this measurement.