A Raspberry Pi-Based Attitude Sensor

Abstract

We have developed a lightweight low-cost attitude sensor, based on a Raspberry Pi, built with readily available commercial components. It can be used in experiments where weight and power are constrained, such as in high- altitude lightweight balloon flights. This attitude sensor will be used as a major building block in a closed-loop control system with driver motors to stabilize and point cameras and telescopes for astronomical observations from a balloon-borne payload.Comment: Journal of Astronomical Instrumentation, Volume 03, Issue 02, November 201

Measurement of limb radiance and Trace Gases in UV over Tropical region by Balloon-Borne Instruments – Flight Validation and Initial Results

“…We have used a compact MEMS-based attitude sensor built in-house by Sreejith et al (2014) to monitor the viewing direction of Environment sensors (temperature, humidity and pressure) are usually employed to measure atmospheric parameters during the flight. Two temperature sensors, internal (inside the payload box) and external (outside the payload box), monitor the temperature of the payload (the internal sensor is placed to ensure that the spectrograph remains within its operational temperature range).…”

“…Our balloon-borne instrumental set-up consisted of three main parts: (i) a spectrograph with an optical fiber and a light collecting lens; (ii) a Raspberry Pi single board computer (SBC); (iii) an optical monitoring camera and environment sensors; and (iv) an attitude sensor designed and developed by Sreejith et al, (2014). All instruments were powered through a 13000 mAh lithium battery with two power settings at 5 W and 10 W. Figure 1 (Left) shows the schematics of the instrumental set-up.…”

“…Figure 6 shows the variation of measured radiance in the two different wavelength bands; the points are the measurements at different heights and the dotted lines represent an exponential fit in agreement with results obtained in 15 Weidner et al (2005). The payload was oscillating too much to obtain useful results below 10 km (Sreejith et al, 2014). Here we have only considered the data above 10 km -this is because the scattering below 10 km is heavily influenced by cloud cover, and the payload had too much oscillations, which has prevented us from obtaining the useful results.…”

Noise modeling and analysis of an IMU-based attitude sensor: improvement of performance by filtering and sensor fusion

“…The gyroscope gives precise values over short time duration but drifts for longer observations [3], while the converse is true for the accelerometer: there is no drift over long periods of time but a significant jitter occurs on short time scales (0.330…”

“…In balloon-borne astronomical payloads, it is essential to determine the attitude of the payload to point the detector/telescope to the desired direction, for which several attitude determination techniques are usually used: star sensors, sun sensors, IMUs, gyroscopes and/or magnetometers, whose weight might amount to several kilograms [2]. Since our balloon experiments are constrained by the weight of a payload (lightweight category), we have developed a Raspberry Pi (RPi) based attitude sensor (AS) [3]. The weight of this AS is only several grams making it ideal to use in lightweight balloon experiments.…”