Search results for:

71% after 1.5hrs with GPS sounds about right to me based on my experience.
You should get about 5->6 hours with GPS on before the battery will go flat.

I have noticed when there is a lot of stuff drawing power that the % pwr will recover a bit after you switch the power drains off. Hope that helps.

:)

I'm not sure, clkinfogps is very tight on space.
I keep the text is readable to me, so use size 20 LatoFont.

Doubling the image size would probably mean I would have to take the spaces in the Grid reference which would make it much harder to read.

I think it is personal choice, but do agree its a dangerous thing to do. Personally I would never wear headphones on a bike or in a car. I do see people do this. I dont feel safe on a bike unless I can hear what is around me.

I do recall that LSD was first experienced whilst riding a bike.
https://www.bikingbis.com/2013/04/19/wor­lds-first-lsd-trip-happened-on-a-bike-ri­de/

NOTE: I am not advocating LSD and would never do it. Besides if you take to much LDS you end up with dyslexia.

PR pending review.

My version shows MON 30 for the text instead of MON. The image would not be changed. To me it just looks like an icon anyway.

is there a reason the image couldn't be rendered double-size too?

Well I could write code that said if its the clkinfocal then double the size but leave everything else the same. But there is no way I could double render something like clkinfogps as it would be too large for the screen with the length of the text that has to be displayed.

I'll see if I can do mod with settings then.

In clockinfocal - I find the day number in the image is unreadable. The font is too small to read even with my prescription glasses that are meant to give me 20/20 vision.

So I did a small mod to show the day number which I really like. Screenshot below.

Question is - should I edit the existing app OR should I produce a new clkinfocal+ that could be extended with a settings menu to show different date formats and date parts in the text that is shown. Dont want to upset the applecart as some of these apps needs to be lean.

I guess this is a question for @Gordon but interested in what others think.

Was going to calculate step length from height, otherwise we will have to go into how to calculate it etc. Most people know their height but not their step length. All the smart watches I have tried just ask for weight, height, age and gender m/f.

I see this behaviour as well with the HRM to 3 mins.

I have noticed this today. I only have wake on touch on.

Thanks @Gordon, I wanted your view before I jumped in. I will add these as settings in the health app. I will then write some prototype apps to calculate calories etc. Finally once the calorie calculation is felt to be good enough we can add it to the health app.

I reently switched to using wake on touch and realised that it sometimes wakes up when you move your wrist as well (even with wake on twist turned off).

This got me thinking...

I only really want the backlite to work outside of daylight hours. What would be useful would be to change the backlight intensity to 0 during daylight hours and a present during the nightime. I think this would save a lot of power. The schedule could be calculated from sunrise / sunset, we have a module for that.

Any idea's how this could be done in such as way that it is an add on ?
I have also noticed that you cant set the LCD backlight to OFF , that 0.1 intensity is the smallest setting.

Agree you would need to walk 100-1000 steps to get an accurate distance measurement and then divide it by the number if steps.

My point was tha GPS is far more accurate at measuring distances rather than trying to infer it from a step count. When people walk they walk a mixture of short and long steps. What I am saying is that distance based on step count is flawed as a concept, the error range builds up very quickly - it can only be used as a rough estimate, which is all those watches will give you.

Gps is very accurate. Far more accurate than step counting an average stride length. Gps is expensive on power consumption.

Do you have suggestions for the defaults. What should average gender be set to? Male or Female? Not set would have to average the values I guess. But the averages will be different for average male or female etc.

Hi All,

Discussion on two threads have lead me to think we need to store some personal data for
(age, height, weight, male/female ). This is so things like calories burned and distance travelled by a persons steps can be calculated.

My suggestion would be that this could be done in two ways.

1) Create an App like My Location called My Profile that adds settings menus to store the values of (age, height, weight, male/female )

OR

2) Add these settings into the Health App.

I suspect that some will have strong views on personal data and the 'My Profile' approach allows those that dont want these values to be present on the watch to be managed by not installing the My Profile app.

Timely question as I have been thinking about this.

I dont think the watches have stride length set anywhere. I suspect the watches that estimate distance are just using an average stride length value - so they are probably wrong (I could be wrong as I have not checked what they do.)

Stride length can be estimated from height using a formula. See the thread on calories.
https://forum.espruino.com/conversations­/391450/#comment17183506

Calculating stride length from height is more accurate than using an average but
a persons actual stride length may be slightly different from their actual if using one of the measurement methods. I am pretty certain my stride length is a couple of cm longer than what is suggested from my height.

However we really need to agree where certain attributes of personal data will be stored.

Some people have strong preferences on personal data (age, height, weight, male/female).
I was about to post about how this could be done. It could be done using a plug in App a bit like 'My Location' works. That way the settings can be added as a plugin app and if anyone
does not want such personal data stored on their watch then they dont install the app. It could also be part of the Health App.

I will start a seperate thread to discuss this in more general.

Basal Metabolic Rate (Calories burned for resting for 24 hours)

https://www.omnicalculator.com/health/bm­r-harris-benedict-equation#how-can-you-c­alculate-your-bmr

Your basal metabolic rate (BMR) is equivalent to the amount of energy (in the form of calories) that your body needs to function if it were to rest for 24 hours.

For men: BMR = 66.5 + (13.75 × weight in kg) + (5.003 × height in cm) - (6.75 × age)

For women: BMR = 655.1 + (9.563 × weight in kg) + (1.850 × height in cm) - (4.676 × age)

For me:
BMR == 66.5 + (13.75 * 80) + (5.003*173) - (6.75*61)
66.5 + 1100 + 865 - 412 => 1619.5 (this is for 24 hours)

For each hour of sleep therefore => 67.5 cals

Step Length Calculation - needed to work out the height to step to MET profile up to 7mph

https://dotorg.brightspotcdn.com/6b/bf/e­07786f54254b9a5e0e9863dcfa9/stride-lengt­h-by-height.pdf

Females: h (inch) * 0.41
Males: h (inch) * 0.415

Conert to metric height

male step length = h (cm) * 0.415 / 100 in meters
female step length = h (cm) * 0.41 / 100 in meters

My height is 5ft 8, 68 inch or 173cm

stepl = 173 * 0.415 / 100 => 0.717m

but do you think setting it to 2 secs
would save a fair share of energy ?

I doubt it will make any difference as the gps will still be fully powered between fixes.

But the proof is always to test and compare.

This link has got MET rates for various activities.

https://www.healthline.com/health/what-a­re-mets#examples

Sitting 1.3 MET to Running 7mph 11.5 METS
We also need the MET count for breathing and sleeping.

I am fairly sure I could leave a fitbit on the desk and at the end of 24 hours it would say I had burned 1800 calories.

But based on the above we could use the heath app steps recorded per hour as a proxy for the level of activity and calculate METs from that.

I am just doing a back of the envelop calculation below, to see if the answer makes sense.

7 MPH is 11.5METS
7 miles => 11265m => 11265 / 0.75 = 15020 steps in 1 hour

Where 0.75 is my stride length (can be approximated from height for the person)
There is a formula somewhere for that, need to find it.

0 steps -> 15K steps in 1 hour
1.3 to 11.5 Mets
So that transcribes to a rate of

(11.5 - 1.3) / 15020 ==> 0.000679 MET per step per hour.

So say I do 2K steps in 1 hour
My MET rate would be 2000 * 0.000679 => 1.358

So I walk 6000 steps in 1 hour => 4.074 METS

I am 80KG

Total calories burned = Duration (in minutes)*(MET*3.5*weight in kg)/200

=> 60 * 4.074 * 3.5 * 80 / 200 => 342 calories

RESULT: Thats a believable answer !!!!

So I think we just need the background constant METS for being alive.
Is it 1.3 (the sitting at a desk value or 1 ?).

QUESTION: Lets calculate 24hours of no exercise (ie no steps)

Total calories burned = Duration (in minutes)*(MET*3.5*weight in kg)/200
Lets try a MET rate of 1.

=> 24 * 60 * 1 * 3.5 * 80 / 200 => 2016 (ooh that is close to 1800 cals).

If we use a MET rate of 0.9 as the sleep value we get 1814 cals. Which is very close to the fitbit value of calories burned when you leave it on the desk for 24 hours.

So I think we have a way to calculate this.

Ideally we would just add this into the Health app and add a setting in the Health App to Age Height (to work out stride length) and Weight in KG.

It should be possible to configure the GPS itself into a low power state, but the documentation
for the chip really isn't great

There was quite a bit of experimentation done a while back by @Mark_M (I think or Mark someone). I would post the thread but I never been that successful with the search tool in the forum.

One of the findings was that certain documentated features did not seem to respond and appear to be working. I have never had time to go back to it to look.

@Fteacher - might be worth testing your watch out on a window ledge where the GPS will get a fix. Download the AGPS data, switch on the run app and get a fix. Then leave it for 4 hours and check what the battery level is. Then repeat and add in the bluetooth heart monitor.

By far the biggest power draw is the gps. Screen updates are less taxing. Be sure to have wake on twist setting set off otherwise your backlite will come on all the time you are moving about.

The gps will discharge the battery from 100%-0% in about 6 hours.

The battery life of the run app could be extended much further by turning the gps on until it gets a fix, off for 30 seconds then on until it gets a fix. I did this in the gpsclock info and was able to use the gps for 48 hours. When moving about the time to get a fresh gps fix from power on will increase and may take a while longer.

It could be done. We would need to define a calculation based on steps for walking then maybe heart rate when moving faster than 5km/hr. 5k/hr is about the upper limit of most people's fast walk speed, anything faster is jogging. We would also need an app to store your weight and maybe height.

Note that fitbit would just say you burned so many calories per hour just sat still. Just breathing burns calories. I think about 1800 per day, depending on weight and heart rate.

As having heart rate on all the time uses a lot of battery the app would maybe have to be a widget that turned heart rate on when faster walking was detected.

A basic approximation could just use weight, elapsed time and steps. I suspect early fitbits did not do much more than that.

I am wondering if the pretokeniser should be on by default.
Over months I experienced occassional hangs and thought it was something with my code.

Since setting pretokeniser OFF (months ago) I can no longer experience those hangs (note they could not be reproduced through some sequence of actions, just seemed to be random every now and again).

Of course 1 report does not make a fact. But I have heard other people talk about the pre-tokeniser. So I wonder if it should be switched off by default and labelled (experimental or caution). When you first start out with your Bangle 2 you are not even aware of this setting. So maybe OFF should be the default position ?