At Philips Health Tech in Drachten, appliances are developed in the personal care (shavers, trimmers, epilators, etc…) and personal health (toothbrushes) domain. For that aim, motors are characterized in such a way that they serve as a model for complete drive-train calculations. Until now, only an indirect method is used to check the accuracy of these characterizations. A direct method – by using a torque sensor – would be more accurate. Next to that, it is necessary to know accurately the load of the main function of an appliance. Until now very low loads cannot be measured accurately. This torque sensor can – potentially – also measure (very) small loads.

The torque sensor should be handled with care. It consists of a flexible resistive bridge between two masses. Basically, this means that the sensor can easily start to resonate by using the wrong control mechanisms. Furthermore, when overloading the sensor, it can be destroyed.

The following elements are part of the investigation:

1. Investigate the torque sensor concept analytically and by (dynamic) simulations when a motor under test and a break motor is coupled:
   1. Get understanding of the system
   1. Investigate options / concepts that give the least amount of resonance / highest damping
   1. Investigate options / concepts how to control the setup.
   1. Investigate options / concepts that prevent the sensor for overloading   
      
      
2. Implement electronics / software to control the system and to measure the torque
   1. Investigate and implement the communication protocol
   1. Investigate how to electronically control the break motor and implement this.
   1. Make it possible to get the characteristics of a motor
   1. Make Python software and (user) interface to automize point b and c
   1. Other (tbd)
      
      
3. Investigate the torque sensor concept when a pulsating load – e.g. a trimmer – is coupled to it.
4. See the subitems under 1)
   
   

Note: Depending on the progress, not all items might be part of the investigation
Initiator/Supervisor: Bernardo Mulder