SLYU064A June   2023  – December 2023 TMAG3001 , TMAG5170 , TMAG5170-Q1 , TMAG5170D-Q1 , TMAG5173-Q1 , TMAG5253 , TMAG5273

 

  1.   1
  2.   Abstract
  3.   Trademarks
  4. 1Introduction
  5. 2Joystick Design
    1. 2.1 Establishing Form Factor
      1. 2.1.1 Choosing Mechanical Implementation
      2. 2.1.2 Choosing Magnetic Implementation
    2. 2.2 Magnet Sensor Placement
    3. 2.3 Design Calculations
    4. 2.4 Post Processing
    5. 2.5 Prototyping and Bench Testing
    6. 2.6 Error Sources
      1. 2.6.1 Mechanical Hysteresis
      2. 2.6.2 Nearby Material Influence
      3. 2.6.3 Fulcrum Slippage
      4. 2.6.4 Offset
  6. 3Lever Design
    1. 3.1 Establishing a Form Factor
      1. 3.1.1 Choosing Mechanical Implementation
    2. 3.2 Magnet Sensor Placement
    3. 3.3 Design Calculations
    4. 3.4 Prototyping and Bench Testing
    5. 3.5 Error Sources
  7. 4Summary
  8. 5References
  9. 6Revision History

4 Summary

This application note demonstrated that Hall effect sensors can be used in joysticks and levers. The design flow for each example was presented starting with deciding the general mechanical form and the possible magnetic implementation. Subsequently, design calculations were executed through the TI-Magnetic-Sense-Simulator developed by TI. This tool provided an initial look at high level feasibility for the magnetic position sensing implementation chosen for the joystick or lever. After tackling the hardware design, software algorithms were presented on how measurements from the Hall-effect sensors can be translated into angle values that are more perceptually relate-able to the end user.

Following the post processing algorithms, discussions on prototyping and bench testing were divulged. The bench testing served to substantiate the idea that Hall-effect sensors can be used in joysticks and levers, and are not just hypothetical conjecture supported only by simulation. These bench tests though did reveal that there can be deviation from the simulation results, and is instrumental in finding errors not accounted for in the early stages of design. Consequently, the notable errors for the designs in this application note were presented. With the design flow presented in this document, the reader has the details to quickly mimic, iterate, and possibly improve upon the designs presented.