This page gives an overview about the required components and lists advantages and disadvantages for each of them.
Also included must be:
- prize
- power consumption
- size and weight
- possibly required modules or connectors for the micocontroller communication
- if nessecary: a circuit plan (created with Eagle)
Frame
DJI FlameWheel F450
- Cost: 169€
- Size: 450mm Diagonal
- Weight frame alone: 282g
- Takeoff Weight: 800g-1200g (1600g? Depending on sources)
- Will need cable ties
- Power distribution board already built in
- Propellers included
Microcontroller
Raspberry Pi 2 Model B:
- a lot of existing projects and help
- only 40 GPIO Pins
- extension-board available (http://www.gertbot.com/) for real-time tasks and controlling of actors and sensors (easy to use with existing libraries)
- Price: Farnell £40.00
- size: width:130mm, height:15mm, depth:80mm
- weight: 0.25 kg
weight: 59g
size: heigth: 85 mm, width: 56 mm, depth: 17 mm
power consumption: http://raspi.tv/2015/raspberry-pi2-power-and-performance-measurement
Hardware:
- Prozessor: ARM710 with 900MHz
- RAM: 1024 MB
price:
Reichelt: 37,95 €
BeagleBone Black
In contrast to Raspberry Pi :
- better I/O capabilities with 7 channel 200kHz 12-bit ADC, 8 PWMs, 4 UARTs, quadrature encoder hardware
- don't have to buy additional components to connect up many more sensors and actuators
- large number of PWM channels on the Bones make them better for motors
- better real-time control with two 200MHz, 32-bit RISC programmable real-time units (PRUs)
- approximately 20 books available for texts, reference and projects
weight: 39.68 grams
size: heigth: 86 mm, width: 53 mm
power consumption: http://www.farnell.com/datasheets/1819364.pdf?COM=DesignCenter in section 6.1.7
Hardware:
Processor: AM335x 1GHz ARM® Cortex-A8
512MB DDR3 RAM
4GB 8-bit eMMC on-board flash storage
3D graphics accelerator
NEON floating-point accelerator
2x PRU 32-bit microcontrollers
Price:
Farnell element14: €46.16 (Price is before tax)
RS Components: £39.99
Battery
3S will presumably be enough
For weight reasons: probably ca. 2000mAh?
Price: ca 20€ (might be less, depending on shop and our choice)
Output: 11,1V
--> Voltage Controller (e.g. IC7805) required, probably multiple? Low cost, Arndt will bring some, maybe we can buy them off him, if he doesn't mind?
--> May need some that are lossless? -> mc35063 but higher cost!
--> Some people say we will need a step down module, because Voltage Controllers will offer too much variation in their voltage/current: http://www.electrodragon.com/product/lm2596s-adj-dc-dc-small-tiny-adjustable-step-down-module-3-40vin-1-5-35vout/ is recommended, but only outputs 3A?
==> Need a lot more information, might look into it more tomorrow?
LiPo-Warners
Cost: 5-10€
Connection to the microcontroller will have to be done by ourselves. So I don't know how many pins we might need. Will have to talk to someone who might know more, internet doesn't really give much insight. Maybe I'll make a post about it somewhere?
Motors
DJI Motor 2212/920 rpm/V
- Voltage: 11,1 bis 14,4V
- Standard Current: 15-25A
- Max Current: 30A
- Required Batteries: 3S-4S LiPos
- Weight: 56g each (including Propeller Adapter)
Calculation Site: http://www.ecalc.ch/xcoptercalc.php?ecalc&lang=de
In case this helps anyone...I don't think my calculations were correct so it didn't help me much
Electronic Speed Controller (ESC)
DJI Brushless Regler 30A OPTO (?)
Don't need much information. They'll work with our setup.
Replacement parts for Controller/Arms: https://copterdeluxe.com/Multi-Rotor-Copter-Ersatzteile-DJI-Hobby-F450 (Currently not available?)
Gyro & Acceleration Sensors
MPU-9150. All in one kit. Gyro, Acceleration and Compass.
Links: Amazon: http://www.amazon.de/GY-9150-MPU-9150-Achsen-Kompass-Accelerometer-SE05014/dp/B00VRJEA7C/ref=sr_1_1?ie=UTF8&qid=1430578388&sr=8-1&keywords=MPU-9150
Specification: http://www.invensense.com/mems/gyro/documents/PS-MPU-9150A-00v4_3.pdf
Cost: 20.59€
Operating Voltage Supply: 2.4V-3.46V
Logic Supply Voltage: 1.8V +- 5% or VDD
Proximity Sensors
4-Pin Ultrasonic-Module HC-SR04
Links: Amazon, datasheet, short instructions
Cost: 10 x approx. 2€ ≈ 20€
Power Supply: +5VDV, 15mA working current
Pins: 2 GPIO, VCC, GND
- VCC = +5VDC (GPIO)
- Trig = Trigger input of Sensor (GPIO)
- Echo = Echo output of Sensor (GPIO)
Important: Outputs 5V. If the microcontroller can only handle 3.3V inputs, we need to build an easy voltage divider. - GND = GND (GPIO)
Minimum sensor recognition distance:
> Sensor’s minimum-distance does not have to be much smaller than 20cm (8“).
Infrared:
- Binary Output: detects whether an object is within a threshold distance
- Multiple Bit Output: detects the more or less accurate distance to an object
Pro:
- Quality products comparatively cheap
- In some cases very high resolution (up to 1 mm)
Contra:
- Problems with sun light
- Problems with recognition of dark or black objects
- Small range sizes
Recommendation after some research:
Sharp GP2Y 0A02 (ca. $11, 20cm – 150cm Range, Analogue Output)
http://acroname.com/products/SHARP-GP2Y0A02YK0F-IR-PACKAGE
(see also: http://acroname.com/articles/sharp-infrared-ranger-comparison for comparison)
Ultrasonic
Pro:
- Not depending on optical properties of an object -> more reliable in common usage
- Larger range sizes
Contra:
- Usually higher prize
- Lower resolution (2-3 cm)
- Problems detecting acoustic quieting objects
Recommendation after some research:
Parallax PING Ultrasonic Sensor (ca. $29, 2cm – 300cm Range)
https://www.parallax.com/product/28015
(maybe cheap replacement: http://www.dx.com/p/hc-sr04-ultrasonic-sensor-distance-measuring-module-133696?Utm_rid=37202148&Utm_source=affiliate#.VTsyqa3tmko)
Radio Telemetry Kit
Aukru HC-06 Wireless 4 Pins Bluetooth RF Transceiver Serial Module
Links: Amazon, instructions, instructions, instructions
Cost: 9€
Power Supply: 3.3V - 6V, approx. 50mA
Pins: 2 GPIO, VCC, GND
- VCC = +3.3VDC / +5VDC (GPIO)
- TXD = Trigger input of Sensor (RXD Digital 0)
- RXD = Echo output of Sensor (TXD Digital 1)
- GND = GND (GPIO)