Status: In production
On the left: 10DoF unit with mini-USB and internal LipO charger.
On the right: 10DoF with Molex Pico-Blade power connector (without internal LiPo charger).
The SmartLogger and GSOF-Miniature-Pitot-Tube connected together to achive a full avionic telemetry data measurement solution.
The small structure and light wieght solution in most interesting for RC-Model users.
Concept:
The SmartLogger is a light weight & low power Data-Logger device with RTC, integrated 6DoF-Inertial Sensors, 3-Axis magnetometer, thermometer, high sensitivity barometer and 1x aux analog input.
It is designed to be used in academic research as well as home use.
The Loggers power consumption is very low and can operate without charging its main battery up to 1month (When using a 240mAh LiPo).
The exact operation time depends on the loggers working profile (Active sensors, Sampling rate, Compression).
The SmartLogger can be used as a regular logger or as an IMU that transmits inertial telemetry data in real-time.
NVM storage memory:
The SmartLogger support one of the non-volatile storage memory configurations:
- 2 MByte FLASH
- 4 MByte FLASH
- 8 MByte FLASH
- 8 MByte FLASH
Communication:
The communication with the logger is done over Blue-tooth using standard COM profile.
A special version with BLE tranceiver also exists.
The Smart-Logger supports the following operation (via the communication channel):
- Real-Time transmission of the telemetry readings
- Logged data transmission (Log-Download).
- Configuration of working profile (Sampling rate, data-compression type, active sensors, power management modes)
- Firmware update
Communication Range:
25m - Tested in an open-field with laptops internal BT
25m - Tested in an open-field with laptops internal BT
1.5 - Tested with a desktop computer with tiny USB dongle.
Measurement modes:
The SmartLogger support the following measurement modes:
- Continuous: sampling at sampling frequency of 0.05 to 20hz
- On-ChangeDetect: Logger is triggered only if a change in one of the sensors was detected. This option helps to reduce power consumption and memory consumption.
Data Compression:
The SmartLogger support three types of data formats:
- Raw-16bit (Native data of sensors without compression).
- Raw-8bit with binary scale down option.
- MuLaw compression (16bit to 8bit).
- Raw-16bit (Native data of sensors without compression).
- Raw-8bit with binary scale down option.
- MuLaw compression (16bit to 8bit).
The SmartLogger support the following operation modes:
1. OFF (Standby)
2. Real-time TX
3. Logging
4. Log down-load
5. Real-Time TX while logging
6. Log down-loading while logging
7. Real-Time TX while logging while log down-loading
Specifications:
Sensors: Any combination up to 3-Axis-Accelerometers, 3-Axis-Gyro, Temperature, Barometer, 3-Axis-Magnetometer is possible. Fewer sensors will result in longer effective logging time.
Aux Analog Input: 0 to 3v, 10bit resolution (~3mV)
Sampling Period: 30[sec] to 50[ms] in 5[ms] resolution.
Maximum Sampling-Rate:
Maximum Sampling-Rate:
All sensors: 9[Hz] (Barometer in acquisition-time of 3.4ms)
3x types of sensors: TBD[Hz]
2x types of sensors: TBD[Hz]
Single sensor of any type: 20[Hz]
Dimensions: 30x25x14mm
Weight: without battery: 8gr (10DoF version), 5.5gr (3DoF version)
Weight: without battery: 8gr (10DoF version), 5.5gr (3DoF version)
Battery type: LiPo 240mAh (6gr)
Battery type: LiPo 350mAh (9.5gr)
Battery life: more then 1-month (3-Accl, Sampling-Rate: 1hz, 240mAh)
Power consumption: 3v*180uA = 540uW (@0.2SPS, 3x accelerometers, Log-Enable, No compression)
Communication protocol: Bluetooth-2 or BLE / COM 230400 / 115200bps
Memory: Onboard 16Mbit / 32Mbit / 64Mbit FLASH
Auxilery Analog Input:
The SmartLogger has a single analog input port. If not connected to any source it will measure the internal battery voltage.
The AUX connector also include ground and 3.3v/100mA output.
Any sensor with output voltage between 0 to 3v can be used.
Typical sensors that can be connected are:
- Pitot-Tube for air-velocity measurements.
- Load-Cell for wiegth or force measurements.
- Remote temperature sensor (e.g. LM35 or RTD)
- Light intencity sensor
- Motion sensor
- Current / Voltage sensor
- Sound intencity sensor
- Geiger sensor (With analog output)
Firmware Specifications:
The entire Smart-Logger application is build over the GS-Real-Time-Operating-System and drivers.
The GS-RTOS is highly efficient cooperative multitask OS developed especially designed for the PIC12F, PIC16F, PIC18F, PIC24 & dsPIC family from Microchip.
For more details refer to RTOS specification document.
The GS-RTOS is extended with three powerful features:
1. The GS-Device-Control-Network protocols stack (DCN).
The unit can communicate over Point-to-Point communication line or Half-duplex networks according to the DCN specifications. For more details refer to DCN specification document.
The unit can communicate over Point-to-Point communication line or Half-duplex networks according to the DCN specifications. For more details refer to DCN specification document.
2. GS-System-Monitor-Application (SMA).
The SMA an internal task with memory mapped interface which gives the user full remote access over the unit.
For more details refer to the GSOF_RTOS specification document.
The SMA an internal task with memory mapped interface which gives the user full remote access over the unit.
For more details refer to the GSOF_RTOS specification document.
3. The GS-Virtual-RPN-Machine (VRM).
The VRM is a stack based virtual processor with over 130, 8bit and 16bit commands. The VRM gives the unit its stand alone capabilities. The VRM has full access to all the SMA registers and all the MCU RAM/EEPROM/FLASH regions. The unit can run one user VRM program as a background task. The VRM can be used to just perform a simple initialize script or complex control-loop and menu-driven application using LCD & keypad. For more details refer to VRM specification document.
The VRM is a stack based virtual processor with over 130, 8bit and 16bit commands. The VRM gives the unit its stand alone capabilities. The VRM has full access to all the SMA registers and all the MCU RAM/EEPROM/FLASH regions. The unit can run one user VRM program as a background task. The VRM can be used to just perform a simple initialize script or complex control-loop and menu-driven application using LCD & keypad. For more details refer to VRM specification document.
User Application:
The Smart-Logger is provided with a Python based operating interface.
The interface application is a user friendly GUI to quick and easy configuration, operation and monitor of the Smart-Loger
Features:
Python based code. Compatible with Windows and Linux OS.
Python based code. Compatible with Windows and Linux OS.
Full control over the Smart-Logger unit
Real-time graphs of all active sensors
Real-Time logging to file support
Firmware update
Main screen of the GUI + Real-Time plots
Smart-Logger sensors configuration values
Barometer & temperature sensor calibration values
Sensors linear calibration values
In the future they wil be saves in the Smart-Loggers NVM
Power consumption at different working profiles:
All measurements were done with active logging and tranceiver-OFF
Current consumption can and will be reduced in future versions.
Gyro-meter – When in sleep-mode will consume 5[uA].
When not in sleep-mode, will consume:
1.5[mA] +0.024[mA]*SampleRate
1.5[mA] +0.024[mA]*SampleRate
Barometer - Value should be multiplyed by sampling rate:
Sample time[ms]:| 4.5| 7.5| 13.5| 25.5 |
Barometer [uA] |3.6| 6.0| 10.8| 20.4 |
Barometer [uA] |3.6| 6.0| 10.8| 20.4 |
Magnetometer [uA]: 240 +0.5*SampleRate
* In next version the constant 240uA current will be reduced to ~5[uA]
Comming soon...
5sps, Raw16, 3-Accl, 3-Gyro
10sps, Raw16, 3-Accl, 3-Gyro
5sps, MuLaw, 3-Accl, 3-Gyro
10sps, MuLaw, 3-Accl, 3-Gyro
10sps, Raw16, 3-Accl, 3-Gyro
5sps, MuLaw, 3-Accl, 3-Gyro
10sps, MuLaw, 3-Accl, 3-Gyro
1sps, Raw-16bit, Temperatur + Barometer
1sps, Raw-16bit, 3-Mag
1sps, Raw-16bit, Time + All-Sensors
10sps, Raw-16bit, Time + All-Sensors
1sps, Raw-16bit, Time + All-Sensors
10sps, Raw-16bit, Time + All-Sensors
Memory storage estimation:
The estimated amount of log data is fairly simple to calculate. Each sensor has a known number of bytes and should be multiplied by the sampling rate and logging hours.
The table below describe the number of bytes used for each sensor in each compression type.
In the change detection mode even if no change is detected a log will be saved every 32[sec].
each block of 64KB has a header of 16bytes. The header contains all working profile information + RTC time.
The RTC time is a 48bit number in milliseconds resolution.
Example #1:
Active sensors: Termometer + Barometer
Compression: Any type
Sampling rate 0.1[hz] (every 10[sec])
NVM: 32M[bit] == 4M[byte] == 4*1024*1024[byte]
hours = 4*1024*1024 / (2+3) * (1/0.1) /60 /60 ~= 1165[hour] = 97[days]
*The 10DoF unit with 1000mAh is capable to work the above period of time.
*Next version of 10DoF with 240mAh will be capable to work the above period of time.
Example #2:
Active sensors: Time-Tag, Accl, Gyro, Termometer, Barometer
Active sensors: Time-Tag, Accl, Gyro, Termometer, Barometer
Compression: RAW16
Sampling rate 20[hz] (every 50[msec])
NVM: 32M[bit] == 4M[byte] == 4*1024*1024[byte]
hours = 4*1024*1024 / (2 +3 +3 +2 +3) * (1/20) /60 /60 ~= 4.5[hour]
Sampling rate 20[hz] (every 50[msec])
NVM: 32M[bit] == 4M[byte] == 4*1024*1024[byte]
hours = 4*1024*1024 / (2 +3 +3 +2 +3) * (1/20) /60 /60 ~= 4.5[hour]
*The 10DoF unit with 240mAh is capable to work the above period of time.
Example #3:
Active sensors: Time-Tag, Accl, Termometer + Barometer
Compression: MuLaw
Sampling rate 10[hz] (every 100[msec])
NVM: 32M[bit] == 4M[byte] == 4*1024*1024[byte]
hours = 4*1024*1024 / (2 +(6/2) +2 +3) * (1/10) /60 /60 ~= 11[hour] = 0.5[days]
*The 10Dof unit with 240mAh is capable to work the above period of time.
Examples of interesting log files:
Here are some tests I made with the 1st two prototypes:
(You may download them by clicking on the link)
- 6min of RC-flight (To 1400feet, dive, Inverted flight)
Comming soon...
- 48h log of temperature and accelarometers inside the refrigerator (Located in door).
- 48h log of temperature and accelarometers inside the refrigerator (Located on mid shelf). - N
- 15min walk in the park1 (5hz, accl, barometer)
