CanHap: Lab3

Ahmed Anwar
4 min readApr 6, 2021

Created by: Ahmed Anwar


The goal of this lab is to communicate three expressions using grounded force feedback from the Haply device only.

Expression Selection

I started off the process of word selection by keeping three goals in mind. Firstly, the words should be mapped to the haptic feedback. Secondly, the three words should be distinguishable without any external assistance. Lastly, I realized that representing emotional expressions would be more aptly represented using the Haptic Feedback than any arbitrary expression.

In the next step, I explored the different forms of feedbacks that can be represented by the Haply device. To represent different elements in the sketch, I used the Fisica library because it provides the functionality to render different feedbacks upon interaction with the end-effector. During this exploration process, I played with different properties of the Fisica objects such as damping, velocity and location. However, other than these, there was not a lot to render which is I guess a limitation of Haply if it is constrained by no visual mode.

My initial set of words were, excited, angry, soothing, slow, lazy. Subsequently, I felt that a lot of words had an overlap in their meaning. Like slow and lazy could be clubbed together. To get some assistance, I then looked at the valence-arousal model for emotion classification. This helped me to narrow down three words to Soothing, Angry & Tired


The design phase was challenging given the constraint of providing no visual feedback to the user. Another constraint was using only one sketch to represent the three expressions. Therefore, I decided to create three different regions using Fisica in the sketch to represent the three expressions.

Rough sketch design

Another design constraint was that the user must not know the identities of the regions before hand or visually from the sketch. Therefore, I felt that it was important to keep the the look of the final visual same.

Final Sketch in Processing

Word 1: Soothing

“Soothing” has low arousal and positive valence. This word was represented by changing the velocity attribute when the user moves into the Region 1. There are two Fisica Fbox objects in this region which propel the end-effector in the opposite direction. Since, the Fboxes are parallel so, the user feels a constant vibration that is soothing. Using value of 70, was appropriate as it did not produce any aggressive oscillations. Upon user testing, one of the participant referred to it as a massage which validates this effect.

Word 2: Angry

“Angry” has high arousal and negative valence. Representing it was easy as during the previous labs, I had made many errors that made the haply oscillate aggressively. However, in this lab I could put it to some actual use. I implemented this effect by changing the position of the end-effector in the opposite direction upon touching the Fbox objects. So, when the user moves into Region 2, the end-effector keeps on bouncing vigorously, between the two walls and the user feels aggressive movements on his hand.

Word 3: Tired

“Tired” has a low arousal and negative valence. This was inspired by the dampening effect of the Fisca object whereby, the user feels difficult to move in the dampened region in the sketch. There could be other contexts that could convey other meanings such as “sad” or “lazy” but I felt that “Tired” was the most appropriate in this context.



User testing

I tested the sketch on my younger sibling and 2 cousins (age 16,18). They had never heard of HCI. Therefore, I briefed them about HCI little before the task but did not disclose my own words. In addition, I also asked them to describe their experience using simple adjectives. They were given many opportunities to interact with the Haply under my supervision. After listening their feedback, I gave them options from a list of adjectives that best describes their experience. The feedback is shown in the table below. We can see that most of the responses aligned with the actual word. For instance, “Massage” is apt in describing “Soothing”. However, “Crazy” is bit off from Angry but still represents a negative connotation word.


This was an interesting lab as it pushed us to represent expressions using the Haply. I felt that the constraint of no visual aid was vey important as it allowed us to render feedback that could ultimately be used to assist visually impaired people.

Secondly, I feel that the number of interactions that can be achieved by Haply are very limited. Due to this reason, I could not add a lot of context to each expression which also prevented the users to not fully immerse into the context of the expression. Therefore, I believe that having higher DoF devices like Phantom could be used to provide richer linguistic and emotional expressions.