Help!!

[Matthopeful]

Hi, I wondered if there was any one out there would be interested in helping me with a project enabling me to compare foot pressure in real time ideally wire's, displaying results with let's, green even, reds weight left or weight right?

 

[dougy83]

Hi, I wondered if there was any one out there would be interested in helping me with a project enabling me to compare foot pressure in real time ideally wire's, displaying results with let's, green even, reds weight left or weight right?

Hi. Could you provide more information about the mechanical arrangement and how it is used? Maybe a rough sketch?

 

[billybob]

Hi. Could you provide more information about the mechanical arrangement and how it is used? Maybe a rough sketch?

I would like to help, but we need more info.

 

[Matthopeful]

Hi, yes it's for the stirrups when riding a horse, so I can compare left/right balance whilst riding, the led's would need to be fixed to the headpiece behind the horses ears on the bridle.. for safety reasons the more wireless it is the better.. Thanks so much, I've no idea where to start..
Matt

 

[dougy83]

Bare in mind that wireless is more difficult than wired, especially if you've no experience.
My first approach for what you described might use the following parts:

1. A metal double-eye buckle with strain gauges fitted, and the reader, microcontroller, RF transmitter and battery. This is fitted between the stirrup and its strap.
   1. Gauges: BF350
   2. Gauge interface: HX711
   3. microcontroller: any (you may find e.g. Arduino easy to use for developing, and then just use the bare microcontroller for the final device)
   4. RF transmitter: micro-sized 315/433MHz, e.g. H34A-433, or nrf24l01
   5. Battery: CR2032
2. The bridal-mounted device, with LEDs, microcontroller, RF receiver and battery.
   1. microcontroller: any
   2. RF receiver: any superhet that matches the transmitter, or nrf24l01
   3. Battery: 2x AA

The stirrup-mounted device presumably needs to be small. To make the small battery last a while, its microcontroller and gauge/interface can be kept in low power mode most of the time, and woken up fully when the strain gauges have changing value (i.e. the device is being used). A periodic transmission of the gauge reading is transmitted, along with an identifier of the device (e.g. "Left foot"). You may wish to transmit the value up to maybe 10 times a second. That's all this device has to do; just read, transmit, and power down.

The head-mounted device doesn't have to be as small, and can take advantage of a larger battery (this is important also because the LEDs and RF receiver will be using more power than the transmitter devices). The microcontroller in this device just has to decode the RF signal, then light the LEDs appropriately. I'd put a power switch on this device, so you don't have to worry about when it should be running.

There are libraries for the Arduino for interfacing most of this hardware. All the electronics parts are available on ebay as modules, to make development easier.

 

[Matthopeful]

Wow thank you, it seems a bit like a foreign language to me, but will give it a go.. Many thanks Matt

 

[Matthopeful]

So your thinking strain gauges rather than pressure pads?

 

[dougy83]

It's not the simplest first project, but definitely doable.

If you use the nRF24L01 transceivers on the stirrup devices, you can configure them as BLE devices which you can monitor from your phone. You could then use the phone as the display (rather than making the extra device with the LEDs), or record the rider's performance to the phone, for display and analysis later on.

 

[dougy83]

So your thinking strain gauges rather than pressure pads?

That was my first thought. Do you have any particular pads in mind?

 

[Matthopeful]

No, I wouldn't have a clue where to start..
Definitely thinking I can display results as I'm riding so I can adjust thi gs in real time, I'll have a look, if it is totally beyond me, would you be interested in me commissioning you to make one up for me? Really appreciate your help!!

Matt

 

[dougy83]

All the best. You can find tutorials for most of the above on Youtube. It should be a fun project. If you send an offer, I'll certainly read it