Hello and welcome to my presentation of our Late-Breaking Work "ActPad – A Smart Desk Platform to Enable User Interaction with IoT Devices".
My name is Sarah Delgado Rodriguez and I am currently finishing my master studies at the LMU Munich.
I am also part of the Usable Security and Privacy Group of the CODE Research Institute Cyber Defense.
In the era of ubiquitous computing, interaction is no longer a one user to one device relationship.
Instead, one user may be in control of many Internet of Things devices.
This becomes apparent, as we take a closer look at one specific setting, that is desks.
A desk setup typically allows many devices to be controlled, such as a computer, lights or speakers.
Beyond the desk, further devices come into play, e.g. printers, projectors, security systems or a coffee machine.
As of now, interaction with these devices is mostly handled separately through different interaction modalities and metaphors.
Centralization requires extensive additional hardware and software to provide interaction capabilities and computational power
– means that are usually available at desks by default.
ActPad bundles the control of multiple ubiquitous devices, by sensing capacitive touch inputs in desk setups.
This work focuses on the implementation of ActPad and the exploration of different use cases.
ActPad is a flexible desk pad, which consists of two layers of polyvinyl chloride.
It is, therefore, easy to integrate into existing desk setups.
Our desk pad is 90 cm wide, 60 cm deep and 5mm high.
It has 40 electrodes, which are all individually wired to a central circuit board.
These electrodes allow to sense touches, based on self-capacitance.
All required sensing and computation capabilities are bundled in the controlling unit,
which contains a raspberry pi 4 and four mpr121 capacitive sensor shields.
It can easily be integrated with existing setups and is mobile due to its reduced size and the provided casing.
To enable touch-recognition on objects, we designed easy-to-use connectors.
These connectors can be attached to an electrode and wired to any object using copper-tape.
They can be rearranged at any time, facilitating flexible user-created object-to-sensor mappings.
Touch-interactions on movable objects can be sensed, by adding a conductive surface to the objects’s bottom and sides.
The conductive surface will transfer touches to the desk pad.
Hence, ActPad has a rich interaction-space, which includes touch-recognition on stationary objects, movable objects and the desk-pad itself.
This interaction space is further extended by the wide range of possible user commands and input modes.
As a first example, our platform enables sequential inputs of unlimited lengths, also including repeated inputs.
Users could, therefore, use the length of inputs to reflect different considerations like frequency of use.
Furthermore, generating multiple touch entries simultaneously is recognized as a single input.
This is similar to shortcuts known from keyboards such as, ctrl + C.
Those interactions where users deliberately hit a sequence to trigger a desired action can be summarized under the umbrella-term of explicit inputs.
The memoralizability of such explicit inputs could be enhanced by metaphoric interactions
- like starting the music play, when a speaker is touched.
However, these challenges could be also completely avoided through implicit input tracking.
For example, users could be logged into their PC in the morning based on their routines
- meaning the order in which they touch different objects on their desk.
Hence, ActPad could be also applied as a mean to track user behavior.
To summarize: We present ActPad, a touch sensing desk pad, which opens novel opportunities for interaction in smart environments.
ActPad senses touches on its 40 electrodes, on connected objects and movable objects.
This allows for an easy integration into existing desk environments .
It also enables various interaction modes - in particular simultaneous, sequential, implicit and explicit inputs.
ActPad’s theoretically unlimited interaction-space can be customized through reusable connectors and user-defined input sequences.
And that brings us to the end. I would like to thank you for your time and attention and please feel free to contact us via mail. Thank you.