Rapid deployment of new tactile sensors is essential for scalable robotic manipulation, especially in multi-fingered hands equipped with vision-based tactile sensors. However, current methods for inferring contact properties rely heavily on convolutional neural networks (CNNs), which, while effective on known sensors, require large, sensor-specific datasets. Furthermore, they require retraining for each new sensor due to differences in lens properties, illumination, and sensor wear. Here we introduce TacViT, a novel tactile perception model based on Vision Transformers, designed to generalize on new sensor data. TacViT leverages global self-attention mechanisms to extract robust features from tactile images, enabling accurate contact property inference even on previously unseen sensors. This capability significantly reduces the need for data collection and retraining, accelerating the deployment of new sensors. We evaluate TacViT on sensors for a five-fingered robot hand and demonstrate its superior generalization performance compared to CNNs. Our results highlight TacViTs potential to make tactile sensing more scalable and practical for real-world robotic applications.
Figures & tables
Fig. 2: Examples of tactile images from different sensors: Evident variation in the tactile images collected from different TacTip-style sensors.
Fig. 3: TacViT pipeline: a tactile image is divided into patches which are linearized and fed through a transformer encoder. The transformer extracts feature embeddings from the image, which is then passed through a regression head consisting of several fully connected (FC) layers to output pose predictions.
Parameter
Value
Image Resolution
224×224
Patch Size
16 ×16
Number of Patches
196
Embedding Dimension
768
Number of Transformer Layers
12
Number of Attention Heads
12
TABLE I: TacViT Model Hyperparameters and Architecture
Parameter
Value
Number of convolutional hidden layers
4
Number of convolutional kernels
480
Number of fully connected layers
2
Number of dense hidden layer units
512
Hidden layer activation function
ReLU
Dropout coefficient
0
TABLE II: CNN Hyperparameters
CNN
TacViT
Sensor #
z(mm)
Rx(°)
Ry(°)
Fx(N)
Fy(N)
Fz(N)
z(mm)
Rx(°)
Ry(°)
Fx(N)
Fy(N)
Fz(N)
#1
0.1251
1.1292
1.0961
0.1699
0.1688
0.4296
0.0675
1.5379
1.5292
0.1943
0.1970
0.4829
#2
0.1013
0.8702
0.8642
0.1110
0.1093
0.2585
0.0599
0.7189
0.7407
0.0953
0.0725
0.1945
#3
0.0959
0.7548
0.7464
0.1118
0.1071
0.2722
0.0542
0.6676
0.6163
0.0937
0.0992
0.2319
#4
0.0860
0.7934
0.7964
0.1145
0.1137
0.2549
0.0735
0.9455
0.8948
0.0974
0.1093
0.2207
Tr1-Te1
#5
0.0981
0.7263
0.7482
0.1208
0.1225
0.3010
0.0678
1.2899
0.6957
0.0939
0.1012
0.2931
TABLE III: MAE of predicted contact pose and force for all three evaluation experiments (Tr1-Te1, Tr5-Te1, Tr4-TeU) tested on individual five sensors of the robot hand using the TacCNN and TacViT models.
CNN
TacViT
z(mm)
Rx(°)
Ry(°)
Fx(N)
Fy(N)
Fz(N)
z(mm)
Rx(°)
Ry(°)
Fx(N)
Fy(N)
Fz(N)
Tr1-Te1
Mean MAE
0.1013
0.8548
0.8503
0.1256
0.1243
0.3832
0.0646
1.0320
0.8953
0.1149
0.1158
0.2846
Tr5-Te1
Mean MAE
0.0823
0.9642
1.1119
0.1325
0.1303
0.3474
0.0625
1.6514
1.3855
0.1207
0.1065
0.3344
Tr4-TeU
Mean MAE
0.2116
5.7675
4.6977
0.3915
0.4258
0.8221
0.0796
2.7140
1.8330
0.1846
0.1649
0.4338
TABLE IV: Comparison of Mean MAE of predicted contact pose and force for CNN and TacViT models.
Fig. 4: Strip plots showing the distribution of mean absolute error (MAE) using TacViT and CNN on the three evaluation experiments. Each diamond point represents each model trained per method and per experiment (encompassing all distinct training combinations).
Fig. 5: Example scatter plots displaying the predicted vs ground truth value for each pose and force parameter for each experiment using TacViT and CNN. Significant performance degradation can be seen in the CNN, whereas TacViT adapts better to data from an unseen domain.