Ctu

Central Telemetry Unit (CTU)

TODO:

• The GPS Module only has a footprint now. Needs a sch symbol where the pins are mapped to the pins in the footprint. Note: the footprint pins are not numbered but named directly. eg: instead of pin n. 1, the pin number is set ton RST. etc.
• Display module schematic and footprint symbols
• Think about whether Teensy isntalled directly or on the 4848-6000-CP header
  • IP67 requirements?
• Checking all the generated footprints
• Placing all the modules to the PCB
• Exporting as STL and printing the board to check if the modules fit their footprints
• Routing etc.

Description

The Central Telemetry Unit (CTU) is a real-time embedded telemetry system designed to collect, process, and transmit vehicle data wirelessly.

The system integrates GPS positioning, inertial sensing, CAN communication, and long-range RF telemetry into a single embedded platform built around the Teensy 4.1 microcontroller.

Core Capabilities

• High-rate IMU sampling
• CAN data recording
• Real-time LoRa telemetry transmission
• GPS positioning with PPS timing support
• Custom motherboard PCB integration

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Hardware Architecture

Microcontroller

• Teensy 4.1

GPS Module

• MTK3339
  • Integrated module
  • PPS output for timing
  • External patch antenna (10 cm recommended)
  • Sky-facing orientation required

IMU (6-Axis)

• BMI088

LoRa RF

Transmitter

• RAK3172-9-SM-NI

Antenna

• 30 mm lead length

Receiver

• USB or USB-C LoRa Dongle
• Must be compatible with selected transmitter

CAN Interface

• TJA1051 Breakout

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Resources

• ETH Zurich Telemetry Guide