We recently interviewed Ashley Sturgeon, HBK OEM Custom Sensor design engineer, about robotics applications. We talked about design methods as well as the concerns and challenges that today's robotics engineers may encounter.
Read the following interview to learn from a committed professional who works every day to build sensors to create a more intelligent product.
Feel free to comment this insightful interview!
I'm not sure if I would say there is a most frequently used sensor. Robotics is a wide umbrella and the types of sensors used are determined by what's important to the robot’s function and the user. If it is motion control, maybe an IR sensor, encoder, or accelerometer. If it is load readings, then something along the lines of force and torque. The five listed are only a few of many types of sensors. For each type of measurement reading, there are multiple types of sensors with different capabilities that could do the job. To choose, one would decide what measurements are critical to the robots (ie. and autonomous vacuum needs to know how close it is to the nearest object) and what are desired measurements that could enhance the robot (ie. If you add a load cell to a pick and place bot, you could program it to make decisions based on how heavy the package is).
We design sensors out of element bodies. When designing a sensor, we first meet with the customer and talk about their product, what they are looking to measure, and the type of sensitivity they desire. In our business, we work with force and torque, so customers come to us because they are trying to read some kind of load exerted on or exerting by their robot. We discuss the environment that their bot is operating in and the conditions that the sensor would need to withstand.
Typically, customers have an element body in mind that they would like us to work with. If not, we help them figure out which would be best for reading the desired loads. Once the element bodies are chosen, and the part files are sent to the engineers at HBK, FEA analyses are run to understand the strain patterns of the part. The element body may be adjusted in order to optimize it's strain pattern while staying below the yield stress of the part. Once a desirable pattern is achieved, gauge locations are chosen. Through this process, HBK engineers are reviewing the design with the customer.
Once the customer is satisfied with the design, the project moves to a prototyping phase. Once prototypes of are built, we do some preliminary testing in house, then send the sensor to the customer for more testing. Once a final design has been achieved, we can move into full scale production.
Space efficiency, multiple loads (I'm sure there are others, but these are the two I have encountered) ...
As technology evolves, it aims to be more space efficient. To be more space efficient, the parts get smaller and so does the spacing between part surfaces. To address this our team has designed smaller gauges, switched to thinner coatings, and have utilized flex PCBs all to meet sub 1mm tolerances.
In some cases, a customer may want to measure on load, but the robot may be experiencing multiple loads from different directions. In some cases, the application of more gauges and counteract the effects of the other loads, allowing the customer to isolate the signal of the desired load.
Product Development Engineer
Ashley is an HBK OEM Custom Sensor design engineer and a committed professional who works every day to build sensors to create a more intelligent product.