Friday, October 16, 2020

[spreadsheet][ods]Unsprung/rotating mass (wheel/sprocket/tyre) power loss calculator for cars bikes and motorcycles

 In case you're wondering how much power will you get when you replace you wheel or sprocket or tyres to lighter ones, this spreadsheet is for you.

Open in either libreoffice or google docs. 

Realize that the power loss is not only dependent on unsprung mass, but also on other factors such as wind resistance (your vehicle's aerodynamics), mechanical losses etc... unsprung mass is only one of the losses. These other losses changes over the speed in which you're at, so while calculating, apart from dimensions, you've to also enter the speed and the time required to reach that speed in order to determine the power lost because of the wheel/sprocket/tyre. Another reason why you need to enter the speed and time it takes to reach that speed is that power is a function of energy. So if your vehicle takes less time to reach a certain speed, the mass will take less time to attain that RPM, but ultimately will result in having the same energy. Thus, same energy attained in less time means more power taken by up the rotating mass while accelerating.

Only fill the required values in column B against the non-colored cells. The colored cells are calculated values.

Thursday, October 8, 2020

D-Link DWM-222 4G on Linux.

Will work on any new Linux distribution out of the box. No need to install the 'driver's.

In case yours is an old Linux distribution, just eject the detected corresponding cdrom device (/dev/sr0 or /dev/sr1, sr2 etc...) and a modem will be spawned which can be used just as a standard modem using your networkmanager or using wvdial.

In networkmanager or wvdial, just do not set the APN (or INIT3 string), the device will pick it up automatically. Older versions of networkmanager do not allow this, so you may face issues on it. In this caseu use wvdial with a high BAUD rate.