Ham 1 Altimeter

[Ramjet64]

I've started working on an altimeter design I'm calling Ham - (Ham was the first chimp in space).

I'm not sure at this stage if I'll include outputs for Chutes or ancillary devices or just keep it basic with flight datalogging.
I will take the lessons from this altimeter and put it towards a slightly larger and more comprehensive logger.

Attached is a mindmap for the basic operation of the altimeter.

I'd appreciate your valuable input into what features you would like to see on an altimeter with a small footprint
(I'll probably be using the ESP32-D1 with a 0.9: OLED screen and a GY-93 barometer/Accelerometer module.)
I will experiment with data access rates using the IIC and SPI protocols.
Power at this stage will be from an 1S micro drone Lithium Battery.

 

[Hobie1dog]

cool

 

[lr64]

I was at a launch today where deploying the main at 50 feet might have been appropriate. ;-) A little higher, it would have been in the power lines. From 500 feet, it might have drifted into trees, at least if someone was using a parachute on the large size, giving a rate of descent of, say, 15 or 20 feet per second.

One important feature is a manual that is interpretable by a naive user. That goes for almost any device.

 

[Ramjet64]

How about profiles for high, medium and low power rockets?
Or do we keep it purely configurable by the user?

 

[cwbullet]

I like the name.

 

[Spacedog49Krell]

I was looking for more details on the GY-93 but could not find anything. I assume it is an accelerometer/gyro/magnetometer/altimeter fusion module? I find the 3G fusion accelerometer limit only useful for launch detection. I'm waiting for Bosch's proposed fusion module using the 16G accelerometer range.

 

[Ramjet64]

I was looking for more details on the GY-93 but could not find anything. I assume it is an accelerometer/gyro/magnetometer/altimeter fusion module? I find the 3G fusion accelerometer limit only useful for launch detection. I'm waiting for Bosch's proposed fusion module using the 16G accelerometer range.

Sorry about the bum steer. It's a GY-91 module that uses the MPU9250 accelerometer IC.

MPU-9250 features three 16-bit analog-to-digital converters (ADCs) for digitizing the gyroscope outputs, three 16-bit ADCs for digitizing the accelerometer outputs, and three 16-bit ADCs for digitizing the magnetometer outputs. For precision tracking of both fast and slow motions, the parts feature a user-programmable gyroscope full-scale range of ±250, ±500, ±1000, and ±2000°/sec (dps), a user-programmable accelerometer full-scale range of ±2g, ±4g, ±8g, and ±16g, and a magnetometer full-scale range of ±4800µT.

 

[OzHybrid]

Happy to do some beta testing. See you at the launch if it stops raining....

 

[Ramjet64]

GY91 modules and an 8 channel logic analyser arrived today.
Work cut out for the weekend.