LoRa GNSS Compact Wearable Tracker Design
Budget: $250 – $750 USD
# Freelancer Project – Design and Prototype an Ultra-Compact LoRa GNSS Wearable Tracker
## Project Overview
I am looking for an experienced RF/PCB engineer to design, prototype and validate an ultra-compact battery-powered wearable LoRa GNSS tracking device.
This project includes the complete hardware development, mechanical enclosure, prototype assembly and test software.
The objective is to obtain a manufacturable prototype that minimizes size, weight and power consumption while maintaining reliable RF performance.
---
# Mechanical Concepts
Please evaluate both concepts and recommend the most suitable one.
## Option A – Coin Shape
* Maximum diameter: **25 mm**
* Maximum thickness: **8 mm**
* Rounded shape
* Epoxy housing (hard or rubber-like finish)
* Reinforced hole/eyelet for attaching a click ring or similar
* USB-C connector located opposite the attachment hole
## Option B – Curved Rectangular Shape
* Maximum dimensions: **50 × 15 × 15 mm**
* Curved profile to better adapt to belts, straps or collars
* Flexible or rigid-flex PCB if technically advantageous
* Rounded ends
* Epoxy housing (hard or rubber-like finish)
* Integrated attachment solution
The freelancer should recommend which concept offers the best compromise between size, weight, RF performance, manufacturability and battery life.
---
# Hardware Requirements
The device shall include:
* Low-power MCU
* LoRa communication
* Multi-constellation GNSS receiver (GPS/Galileo/GLONASS/BeiDou preferred)
* Rechargeable LiPo battery
* USB-C charging
* 9-axis IMU
* Temperature sensor
* Barometric pressure sensor (if space permits)
* Battery charging and protection circuitry
* Battery level monitoring (fuel gauge preferred)
* RF tag allowing remote reading of the device unique ID
* Low-power sleep capability
The freelancer may recommend equivalent components if they improve performance or reduce size.
---
# Operating Modes
The hardware shall support:
### Mode 1
Deep sleep
* No transmissions
* Minimum possible power consumption
### Mode 2
On-demand transmission
The device only transmits when requested.
### Mode 3
Heartbeat mode
Automatic LoRa transmission every configurable number of seconds.
Default interval:
20 seconds
---
# Battery Performance
The freelancer shall estimate the achievable autonomy for both proposed form factors.
Target:
* Maximum possible operating time
* If technically feasible, at least 6 hours using GNSS with LoRa heartbeat transmissions every 20 seconds
If this target is not achievable within the required dimensions, provide realistic alternatives and explain the trade-offs.
---
# Test Software
Production firmware is **not** required.
Instead, provide simple demonstration/test software compatible with the selected hardware platform and development framework (it does **not** need to be Arduino if another SDK is more appropriate).
The test software shall independently verify:
* LoRa transmission
* LoRa reception
* GNSS positioning
* Battery voltage and charge level
* USB charging
* IMU operation
* Temperature sensor
* Pressure sensor (if included)
* RF tag ID reading
* Deep sleep
* Heartbeat mode
* On-demand transmission
Each hardware function should be individually testable.
---
# Mechanical Requirements
The enclosure should:
* Be as small and light as reasonably possible
* Have rounded edges
* Be comfortable to wear
* Be splash resistant where practical
* Be epoxy encapsulated (hard or rubber-like finish)
* Leave the USB-C connector accessible
* Include an integrated attachment hole or eyelet
The freelancer shall explain any compromises required between dimensions, battery capacity and RF performance.
---
# Deliverables
### Electronics
* Complete schematic
* PCB layout
* BOM with manufacturer part numbers
* Gerber files
* Pick & Place files
* Assembly drawings
* PCB source files (KiCad or Altium)
### Mechanical
* Complete 3D enclosure
* Native CAD files
* STEP files
* STL files
### Software
* Hardware test software
* Source code
* Build instructions
### Documentation
* Component selection rationale
* Battery life estimation
* RF recommendations
* Assembly instructions
* Manufacturing recommendations
* Short validation/test report
---
# Prototype Delivery
The freelancer shall deliver **two fully assembled and fully tested prototypes**.
The project price shall include:
* PCB assembly
* Programming
* Functional testing
* Mechanical assembly
* Final validation
Electronic components, PCB fabrication, batteries, enclosure manufacturing and shipping costs will be paid separately by the client.
Before shipment, the freelancer shall provide a video demonstrating that both prototypes successfully perform all required hardware tests.
---
# Proposal Requirements
Please include:
* Portfolio of similar projects
* Experience with LoRa and GNSS RF design
* Recommended form factor
* Estimated final dimensions
* Estimated weight
* Estimated battery autonomy
* Estimated engineering schedule
* Fixed project price
* Any recommendations to improve the design
The goal is to establish a long-term collaboration for future hardware revisions and commercial versions.
## Project Overview
I am looking for an experienced RF/PCB engineer to design, prototype and validate an ultra-compact battery-powered wearable LoRa GNSS tracking device.
This project includes the complete hardware development, mechanical enclosure, prototype assembly and test software.
The objective is to obtain a manufacturable prototype that minimizes size, weight and power consumption while maintaining reliable RF performance.
---
# Mechanical Concepts
Please evaluate both concepts and recommend the most suitable one.
## Option A – Coin Shape
* Maximum diameter: **25 mm**
* Maximum thickness: **8 mm**
* Rounded shape
* Epoxy housing (hard or rubber-like finish)
* Reinforced hole/eyelet for attaching a click ring or similar
* USB-C connector located opposite the attachment hole
## Option B – Curved Rectangular Shape
* Maximum dimensions: **50 × 15 × 15 mm**
* Curved profile to better adapt to belts, straps or collars
* Flexible or rigid-flex PCB if technically advantageous
* Rounded ends
* Epoxy housing (hard or rubber-like finish)
* Integrated attachment solution
The freelancer should recommend which concept offers the best compromise between size, weight, RF performance, manufacturability and battery life.
---
# Hardware Requirements
The device shall include:
* Low-power MCU
* LoRa communication
* Multi-constellation GNSS receiver (GPS/Galileo/GLONASS/BeiDou preferred)
* Rechargeable LiPo battery
* USB-C charging
* 9-axis IMU
* Temperature sensor
* Barometric pressure sensor (if space permits)
* Battery charging and protection circuitry
* Battery level monitoring (fuel gauge preferred)
* RF tag allowing remote reading of the device unique ID
* Low-power sleep capability
The freelancer may recommend equivalent components if they improve performance or reduce size.
---
# Operating Modes
The hardware shall support:
### Mode 1
Deep sleep
* No transmissions
* Minimum possible power consumption
### Mode 2
On-demand transmission
The device only transmits when requested.
### Mode 3
Heartbeat mode
Automatic LoRa transmission every configurable number of seconds.
Default interval:
20 seconds
---
# Battery Performance
The freelancer shall estimate the achievable autonomy for both proposed form factors.
Target:
* Maximum possible operating time
* If technically feasible, at least 6 hours using GNSS with LoRa heartbeat transmissions every 20 seconds
If this target is not achievable within the required dimensions, provide realistic alternatives and explain the trade-offs.
---
# Test Software
Production firmware is **not** required.
Instead, provide simple demonstration/test software compatible with the selected hardware platform and development framework (it does **not** need to be Arduino if another SDK is more appropriate).
The test software shall independently verify:
* LoRa transmission
* LoRa reception
* GNSS positioning
* Battery voltage and charge level
* USB charging
* IMU operation
* Temperature sensor
* Pressure sensor (if included)
* RF tag ID reading
* Deep sleep
* Heartbeat mode
* On-demand transmission
Each hardware function should be individually testable.
---
# Mechanical Requirements
The enclosure should:
* Be as small and light as reasonably possible
* Have rounded edges
* Be comfortable to wear
* Be splash resistant where practical
* Be epoxy encapsulated (hard or rubber-like finish)
* Leave the USB-C connector accessible
* Include an integrated attachment hole or eyelet
The freelancer shall explain any compromises required between dimensions, battery capacity and RF performance.
---
# Deliverables
### Electronics
* Complete schematic
* PCB layout
* BOM with manufacturer part numbers
* Gerber files
* Pick & Place files
* Assembly drawings
* PCB source files (KiCad or Altium)
### Mechanical
* Complete 3D enclosure
* Native CAD files
* STEP files
* STL files
### Software
* Hardware test software
* Source code
* Build instructions
### Documentation
* Component selection rationale
* Battery life estimation
* RF recommendations
* Assembly instructions
* Manufacturing recommendations
* Short validation/test report
---
# Prototype Delivery
The freelancer shall deliver **two fully assembled and fully tested prototypes**.
The project price shall include:
* PCB assembly
* Programming
* Functional testing
* Mechanical assembly
* Final validation
Electronic components, PCB fabrication, batteries, enclosure manufacturing and shipping costs will be paid separately by the client.
Before shipment, the freelancer shall provide a video demonstrating that both prototypes successfully perform all required hardware tests.
---
# Proposal Requirements
Please include:
* Portfolio of similar projects
* Experience with LoRa and GNSS RF design
* Recommended form factor
* Estimated final dimensions
* Estimated weight
* Estimated battery autonomy
* Estimated engineering schedule
* Fixed project price
* Any recommendations to improve the design
The goal is to establish a long-term collaboration for future hardware revisions and commercial versions.